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 | 161 +++++++++++++++++++++++++++++++++++++++-
1 file changed, 159 insertions(+), 2 deletions(-)
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 11cbd49..7609070 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -28,6 +28,7 @@
#include <linux/device.h>
#include <linux/fs.h>
#include <linux/iommu.h>
+#include <linux/list_sort.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/rbtree.h>
@@ -1199,6 +1200,20 @@ static bool vfio_iommu_has_sw_msi(struct iommu_group *group, phys_addr_t *base)
return ret;
}
+static int vfio_resv_cmp(void *priv, struct list_head *a, struct list_head *b)
+{
+ struct iommu_resv_region *ra, *rb;
+
+ ra = container_of(a, struct iommu_resv_region, list);
+ rb = container_of(b, struct iommu_resv_region, list);
+
+ if (ra->start < rb->start)
+ return -1;
+ if (ra->start > rb->start)
+ return 1;
+ return 0;
+}
+
static int vfio_insert_iova(phys_addr_t start, phys_addr_t end,
struct list_head *head)
{
@@ -1274,6 +1289,24 @@ static int vfio_iommu_valid_aperture(struct vfio_iommu *iommu,
}
/*
+ * Check reserved region conflicts with existing dma mappings
+ */
+static int vfio_iommu_resv_region_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_overlap(iommu, region->start,
+ region->start + region->length - 1))
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/*
* Adjust the iommu aperture window if new aperture is a valid one
*/
static int vfio_iommu_iova_aper_adjust(struct vfio_iommu *iommu,
@@ -1316,6 +1349,51 @@ static int vfio_iommu_iova_aper_adjust(struct vfio_iommu *iommu,
return 0;
}
+/*
+ * Check and update iova region list in case a reserved region
+ * overlaps the iommu iova range
+ */
+static int vfio_iommu_iova_resv_adjust(struct vfio_iommu *iommu,
+ struct list_head *resv_regions)
+{
+ struct iommu_resv_region *resv;
+ struct list_head *iova = &iommu->iova_list;
+ 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) {
+ phys_addr_t a, b;
+ int ret = 0;
+
+ a = n->start;
+ b = n->end;
+ /* No overlap */
+ if ((start > b) || (end < a))
+ continue;
+ /* Split the current node and create holes */
+ if (start > a)
+ ret = vfio_insert_iova(a, start - 1, &n->list);
+ if (!ret && end < b)
+ ret = vfio_insert_iova(end + 1, b, &n->list);
+ if (ret)
+ return ret;
+
+ list_del(&n->list);
+ kfree(n);
+ }
+ }
+
+ if (list_empty(iova))
+ return -EINVAL;
+
+ return 0;
+}
+
static int vfio_iommu_type1_attach_group(void *iommu_data,
struct iommu_group *iommu_group)
{
@@ -1327,6 +1405,8 @@ 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 group_resv_regions;
+ struct iommu_resv_region *resv, *resv_next;
mutex_lock(&iommu->lock);
@@ -1404,6 +1484,14 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
if (ret)
goto out_detach;
+ INIT_LIST_HEAD(&group_resv_regions);
+ iommu_get_group_resv_regions(iommu_group, &group_resv_regions);
+ list_sort(NULL, &group_resv_regions, vfio_resv_cmp);
+
+ ret = vfio_iommu_resv_region_conflict(iommu, &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);
@@ -1434,11 +1522,15 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
d->prot == domain->prot) {
iommu_detach_group(domain->domain, iommu_group);
if (!iommu_attach_group(d->domain, iommu_group)) {
+ ret = vfio_iommu_iova_resv_adjust(iommu,
+ &group_resv_regions);
+ if (!ret)
+ goto out_domain;
+
list_add(&group->next, &d->group_list);
iommu_domain_free(domain->domain);
kfree(domain);
- mutex_unlock(&iommu->lock);
- return 0;
+ goto done;
}
ret = iommu_attach_group(domain->domain, iommu_group);
@@ -1465,8 +1557,15 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
if (ret)
goto out_detach;
+ ret = vfio_iommu_iova_resv_adjust(iommu, &group_resv_regions);
+ if (ret)
+ goto out_detach;
+
list_add(&domain->next, &iommu->domain_list);
+done:
+ list_for_each_entry_safe(resv, resv_next, &group_resv_regions, list)
+ kfree(resv);
mutex_unlock(&iommu->lock);
return 0;
@@ -1475,6 +1574,8 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
iommu_detach_group(domain->domain, iommu_group);
out_domain:
iommu_domain_free(domain->domain);
+ list_for_each_entry_safe(resv, resv_next, &group_resv_regions, list)
+ kfree(resv);
out_free:
kfree(domain);
kfree(group);
@@ -1559,6 +1660,60 @@ static void vfio_iommu_iova_aper_refresh(struct vfio_iommu *iommu)
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 void vfio_iommu_iova_resv_refresh(struct vfio_iommu *iommu)
+{
+ 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;
+
+ 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;
+
+ list_sort(NULL, &resv_regions, vfio_resv_cmp);
+
+ node = list_first_entry(&iommu->iova_list, struct vfio_iova, list);
+ start = node->start;
+ node = list_last_entry(&iommu->iova_list, struct vfio_iova, list);
+ end = node->end;
+
+ /* purge the iova list and create new one */
+ list_for_each_entry_safe(node, tmp, &iommu->iova_list, list) {
+ list_del(&node->list);
+ kfree(node);
+ }
+
+ if (vfio_iommu_iova_aper_adjust(iommu, start, end)) {
+ pr_warn("%s: Failed to update iova aperture. VFIO DMA map request may fail\n",
+ __func__);
+ goto done;
+ }
+
+ /* adjust the iova with current reserved regions */
+ if (vfio_iommu_iova_resv_adjust(iommu, &resv_regions))
+ pr_warn("%s: Failed to update iova list with reserve regions. VFIO DMA map request may fail\n",
+ __func__);
+done:
+ list_for_each_entry_safe(resv, resv_next, &resv_regions, list)
+ kfree(resv);
+}
+
static void vfio_iommu_type1_detach_group(void *iommu_data,
struct iommu_group *iommu_group)
{
@@ -1617,6 +1772,8 @@ static void vfio_iommu_type1_detach_group(void *iommu_data,
break;
}
+ vfio_iommu_iova_resv_refresh(iommu);
+
detach_group_done:
mutex_unlock(&iommu->lock);
}
--
1.9.1
