[PATCH v2 18/22] vfio: add support for flush iommu stage-1 cache

[Liu Yi L <yi.l.liu@intel.com>]

This patch adds flush_stage1_cache() definition in HostIOMUContextClass.
And adds corresponding implementation in VFIO. This is to expose a way
for vIOMMU to flush stage-1 cache in host side since guest owns stage-1
translation structures in dual stage DMA translation configuration.

Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Eric Auger <eric.auger@redhat.com>
Cc: Yi Sun <yi.y.sun@linux.intel.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Alex Williamson <alex.williamson@redhat.com>
Acked-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Liu Yi L <yi.l.liu@intel.com>
---
 hw/iommu/host_iommu_context.c         | 19 +++++++++++++++++++
 hw/vfio/common.c                      | 25 +++++++++++++++++++++++++
 include/hw/iommu/host_iommu_context.h | 14 ++++++++++++++
 3 files changed, 58 insertions(+)

diff --git a/hw/iommu/host_iommu_context.c b/hw/iommu/host_iommu_context.c
index 8ae20fe..e884752 100644
--- a/hw/iommu/host_iommu_context.c
+++ b/hw/iommu/host_iommu_context.c
@@ -113,6 +113,25 @@ int host_iommu_ctx_unbind_stage1_pgtbl(HostIOMMUContext *iommu_ctx,
     return hicxc->unbind_stage1_pgtbl(iommu_ctx, data);
 }
 
+int host_iommu_ctx_flush_stage1_cache(HostIOMMUContext *iommu_ctx,
+                                      DualIOMMUStage1Cache *cache)
+{
+    HostIOMMUContextClass *hicxc;
+
+    hicxc = HOST_IOMMU_CONTEXT_GET_CLASS(iommu_ctx);
+
+    if (!hicxc) {
+        return -EINVAL;
+    }
+
+    if (!(iommu_ctx->flags & HOST_IOMMU_NESTING) ||
+        !hicxc->flush_stage1_cache) {
+        return -EINVAL;
+    }
+
+    return hicxc->flush_stage1_cache(iommu_ctx, cache);
+}
+
 void host_iommu_ctx_init(void *_iommu_ctx, size_t instance_size,
                          const char *mrtypename,
                          uint64_t flags, uint32_t formats)
diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index 465e4d8..6b730b6 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -1274,6 +1274,30 @@ static int vfio_host_iommu_ctx_unbind_stage1_pgtbl(HostIOMMUContext *iommu_ctx,
     return ret;
 }
 
+static int vfio_host_iommu_ctx_flush_stage1_cache(HostIOMMUContext *iommu_ctx,
+                                            DualIOMMUStage1Cache *cache)
+{
+    VFIOContainer *container = container_of(iommu_ctx,
+                                            VFIOContainer, iommu_ctx);
+    struct vfio_iommu_type1_cache_invalidate *cache_inv;
+    unsigned long argsz;
+    int ret = 0;
+
+    argsz = sizeof(*cache_inv) + sizeof(cache->cache_info);
+    cache_inv = g_malloc0(argsz);
+    cache_inv->argsz = argsz;
+    cache_inv->flags = 0;
+    memcpy(&cache_inv->cache_info, &cache->cache_info,
+           sizeof(cache->cache_info));
+
+    if (ioctl(container->fd, VFIO_IOMMU_CACHE_INVALIDATE, cache_inv)) {
+        error_report("%s: iommu cache flush failed: %d", __func__, -errno);
+        ret = -errno;
+    }
+    g_free(cache_inv);
+    return ret;
+}
+
 /**
  * Get iommu info from host. Caller of this funcion should free
  * the memory pointed by the returned pointer stored in @info
@@ -1998,6 +2022,7 @@ static void vfio_host_iommu_context_class_init(ObjectClass *klass,
     hicxc->pasid_free = vfio_host_iommu_ctx_pasid_free;
     hicxc->bind_stage1_pgtbl = vfio_host_iommu_ctx_bind_stage1_pgtbl;
     hicxc->unbind_stage1_pgtbl = vfio_host_iommu_ctx_unbind_stage1_pgtbl;
+    hicxc->flush_stage1_cache = vfio_host_iommu_ctx_flush_stage1_cache;
 }
 
 static const TypeInfo vfio_host_iommu_context_info = {
diff --git a/include/hw/iommu/host_iommu_context.h b/include/hw/iommu/host_iommu_context.h
index 44daca9..69b1b7b 100644
--- a/include/hw/iommu/host_iommu_context.h
+++ b/include/hw/iommu/host_iommu_context.h
@@ -42,6 +42,7 @@
 
 typedef struct HostIOMMUContext HostIOMMUContext;
 typedef struct DualIOMMUStage1BindData DualIOMMUStage1BindData;
+typedef struct DualIOMMUStage1Cache DualIOMMUStage1Cache;
 
 typedef struct HostIOMMUContextClass {
     /* private */
@@ -65,6 +66,12 @@ typedef struct HostIOMMUContextClass {
     /* Undo a previous bind. @bind_data specifies the unbind info. */
     int (*unbind_stage1_pgtbl)(HostIOMMUContext *iommu_ctx,
                                DualIOMMUStage1BindData *bind_data);
+    /*
+     * Propagate stage-1 cache flush to host IOMMU, cache
+     * info specifid in @cache
+     */
+    int (*flush_stage1_cache)(HostIOMMUContext *iommu_ctx,
+                              DualIOMMUStage1Cache *cache);
 } HostIOMMUContextClass;
 
 /*
@@ -86,6 +93,11 @@ struct DualIOMMUStage1BindData {
     } bind_data;
 };
 
+struct DualIOMMUStage1Cache {
+    uint32_t pasid;
+    struct iommu_cache_invalidate_info cache_info;
+};
+
 int host_iommu_ctx_pasid_alloc(HostIOMMUContext *iommu_ctx, uint32_t min,
                                uint32_t max, uint32_t *pasid);
 int host_iommu_ctx_pasid_free(HostIOMMUContext *iommu_ctx, uint32_t pasid);
@@ -93,6 +105,8 @@ int host_iommu_ctx_bind_stage1_pgtbl(HostIOMMUContext *iommu_ctx,
                                      DualIOMMUStage1BindData *data);
 int host_iommu_ctx_unbind_stage1_pgtbl(HostIOMMUContext *iommu_ctx,
                                        DualIOMMUStage1BindData *data);
+int host_iommu_ctx_flush_stage1_cache(HostIOMMUContext *iommu_ctx,
+                                      DualIOMMUStage1Cache *cache);
 
 void host_iommu_ctx_init(void *_iommu_ctx, size_t instance_size,
                          const char *mrtypename,
-- 
2.7.4