This patch provides an interface allowing the userspace to invalidate
IOMMU cache for first-level page table. It is required when the first
level IOMMU page table is not managed by the host kernel in the nested
translation setup.

Cc: Kevin Tian <kevin.t...@intel.com>
CC: Jacob Pan <jacob.jun....@linux.intel.com>
Cc: Alex Williamson <alex.william...@redhat.com>
Cc: Eric Auger <eric.au...@redhat.com>
Cc: Jean-Philippe Brucker <jean-phili...@linaro.org>
Cc: Joerg Roedel <j...@8bytes.org>
Cc: Lu Baolu <baolu...@linux.intel.com>
Signed-off-by: Liu Yi L <yi.l....@intel.com>
Signed-off-by: Eric Auger <eric.au...@redhat.com>
Signed-off-by: Jacob Pan <jacob.jun....@linux.intel.com>
---
v1 -> v2:
*) rename from "vfio/type1: Flush stage-1 IOMMU cache for nesting type"
*) rename vfio_cache_inv_fn() to vfio_dev_cache_invalidate_fn()
*) vfio_dev_cache_inv_fn() always successful
*) remove VFIO_IOMMU_CACHE_INVALIDATE, and reuse VFIO_IOMMU_NESTING_OP

 drivers/vfio/vfio_iommu_type1.c | 59 +++++++++++++++++++++++++++++++++++++++++
 include/uapi/linux/vfio.h       |  3 +++
 2 files changed, 62 insertions(+)

diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index f1468a0..c233c8e 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -2582,6 +2582,54 @@ static long vfio_iommu_handle_pgtbl_op(struct vfio_iommu 
*iommu,
        return ret;
 }
 
+static int vfio_dev_cache_invalidate_fn(struct device *dev, void *data)
+{
+       struct domain_capsule *dc = (struct domain_capsule *)data;
+       struct iommu_cache_invalidate_info *cache_info =
+               (struct iommu_cache_invalidate_info *) dc->data;
+
+       iommu_cache_invalidate(dc->domain, dev, cache_info);
+       return 0;
+}
+
+static long vfio_iommu_invalidate_cache(struct vfio_iommu *iommu,
+                       struct iommu_cache_invalidate_info *cache_info)
+{
+       struct domain_capsule dc = { .data = cache_info };
+       struct vfio_group *group;
+       struct vfio_domain *domain;
+       int ret = 0;
+       struct iommu_nesting_info *info;
+
+       mutex_lock(&iommu->lock);
+       /*
+        * Cache invalidation is required for any nesting IOMMU,
+        * so no need to check system-wide PASID support.
+        */
+       info = iommu->nesting_info;
+       if (!info || !(info->features & IOMMU_NESTING_FEAT_CACHE_INVLD)) {
+               ret = -ENOTSUPP;
+               goto out_unlock;
+       }
+
+       group = vfio_find_nesting_group(iommu);
+       if (!group) {
+               ret = -EINVAL;
+               goto out_unlock;
+       }
+
+       domain = list_first_entry(&iommu->domain_list,
+                                     struct vfio_domain, next);
+       dc.group = group;
+       dc.domain = domain->domain;
+       iommu_group_for_each_dev(group->iommu_group, &dc,
+                                vfio_dev_cache_invalidate_fn);
+
+out_unlock:
+       mutex_unlock(&iommu->lock);
+       return ret;
+}
+
 static long vfio_iommu_type1_nesting_op(struct vfio_iommu *iommu,
                                        unsigned long arg)
 {
@@ -2607,6 +2655,9 @@ static long vfio_iommu_type1_nesting_op(struct vfio_iommu 
*iommu,
        case VFIO_IOMMU_NESTING_OP_UNBIND_PGTBL:
                data_size = sizeof(struct iommu_gpasid_unbind_data);
                break;
+       case VFIO_IOMMU_NESTING_OP_CACHE_INVLD:
+               data_size = sizeof(struct iommu_cache_invalidate_info);
+               break;
        default:
                return -EINVAL;
        }
@@ -2633,6 +2684,14 @@ static long vfio_iommu_type1_nesting_op(struct 
vfio_iommu *iommu,
        case VFIO_IOMMU_NESTING_OP_UNBIND_PGTBL:
                ret = vfio_iommu_handle_pgtbl_op(iommu, false, data);
                break;
+       case VFIO_IOMMU_NESTING_OP_CACHE_INVLD:
+       {
+               struct iommu_cache_invalidate_info *cache_info =
+                               (struct iommu_cache_invalidate_info *)data;
+
+               ret = vfio_iommu_invalidate_cache(iommu, cache_info);
+               break;
+       }
        default:
                ret = -EINVAL;
        }
diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
index e4aa466..9a011d6 100644
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -891,6 +891,8 @@ struct vfio_iommu_type1_pasid_request {
  * +-----------------+-----------------------------------------------+
  * | UNBIND_PGTBL    |      struct iommu_gpasid_unbind_data          |
  * +-----------------+-----------------------------------------------+
+ * | CACHE_INVLD     |      struct iommu_cache_invalidate_info       |
+ * +-----------------+-----------------------------------------------+
  *
  * returns: 0 on success, -errno on failure.
  */
@@ -903,6 +905,7 @@ struct vfio_iommu_type1_nesting_op {
 
 #define VFIO_IOMMU_NESTING_OP_BIND_PGTBL       (0)
 #define VFIO_IOMMU_NESTING_OP_UNBIND_PGTBL     (1)
+#define VFIO_IOMMU_NESTING_OP_CACHE_INVLD      (2)
 
 #define VFIO_IOMMU_NESTING_OP          _IO(VFIO_TYPE, VFIO_BASE + 23)
 
-- 
2.7.4

_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu

Reply via email to