[PATCH v3 2/2] vhost-vdpa: add support for vIOMMU

[Cindy Lu <lulu@redhat.com>]

Add support for vIOMMU. add the new function to deal with iommu MR.
- during iommu_region_add register a specific IOMMU notifier,
 and store all notifiers in a list.
- during iommu_region_del, compare and delete the IOMMU notifier from the list

Verified in vp_vdpa and vdpa_sim_net driver

Signed-off-by: Cindy Lu <lulu@redhat.com>
---
 hw/virtio/vhost-vdpa.c         | 134 ++++++++++++++++++++++++++++++---
 include/hw/virtio/vhost-vdpa.h |  10 +++
 2 files changed, 133 insertions(+), 11 deletions(-)

diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
index 3ff9ce3501..229b8bdfd5 100644
--- a/hw/virtio/vhost-vdpa.c
+++ b/hw/virtio/vhost-vdpa.c
@@ -26,6 +26,7 @@
 #include "cpu.h"
 #include "trace.h"
 #include "qapi/error.h"
+#include "hw/virtio/virtio-access.h"
 
 /*
  * Return one past the end of the end of section. Be careful with uint64_t
@@ -44,7 +45,6 @@ static bool vhost_vdpa_listener_skipped_section(MemoryRegionSection *section,
                                                 uint64_t iova_min,
                                                 uint64_t iova_max)
 {
-    Int128 llend;
 
     if ((!memory_region_is_ram(section->mr) &&
          !memory_region_is_iommu(section->mr)) ||
@@ -61,14 +61,6 @@ static bool vhost_vdpa_listener_skipped_section(MemoryRegionSection *section,
         return true;
     }
 
-    llend = vhost_vdpa_section_end(section);
-    if (int128_gt(llend, int128_make64(iova_max))) {
-        error_report("RAM section out of device range (max=0x%" PRIx64
-                     ", end addr=0x%" PRIx64 ")",
-                     iova_max, int128_get64(llend));
-        return true;
-    }
-
     return false;
 }
 
@@ -173,6 +165,116 @@ static void vhost_vdpa_listener_commit(MemoryListener *listener)
     v->iotlb_batch_begin_sent = false;
 }
 
+
+static void vhost_vdpa_iommu_map_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
+{
+    struct vdpa_iommu *iommu = container_of(n, struct vdpa_iommu, n);
+
+    hwaddr iova = iotlb->iova + iommu->iommu_offset;
+    struct vhost_vdpa *v = iommu->dev;
+    void *vaddr;
+    int ret;
+
+    if (iotlb->target_as != &address_space_memory) {
+        error_report("Wrong target AS \"%s\", only system memory is allowed",
+                     iotlb->target_as->name ? iotlb->target_as->name : "none");
+        return;
+    }
+    RCU_READ_LOCK_GUARD();
+    vhost_vdpa_iotlb_batch_begin_once(v);
+
+    if ((iotlb->perm & IOMMU_RW) != IOMMU_NONE) {
+        bool read_only;
+
+        if (!memory_get_xlat_addr(iotlb, &vaddr, NULL, &read_only,
+                                  &address_space_memory)) {
+            return;
+        }
+        ret =
+            vhost_vdpa_dma_map(v, iova, iotlb->addr_mask + 1, vaddr, read_only);
+        if (ret) {
+            error_report("vhost_vdpa_dma_map(%p, 0x%" HWADDR_PRIx ", "
+                         "0x%" HWADDR_PRIx ", %p) = %d (%m)",
+                         v, iova, iotlb->addr_mask + 1, vaddr, ret);
+        }
+    } else {
+        ret = vhost_vdpa_dma_unmap(v, iova, iotlb->addr_mask + 1);
+        if (ret) {
+            error_report("vhost_vdpa_dma_unmap(%p, 0x%" HWADDR_PRIx ", "
+                         "0x%" HWADDR_PRIx ") = %d (%m)",
+                         v, iova, iotlb->addr_mask + 1, ret);
+        }
+    }
+}
+
+static void vhost_vdpa_iommu_region_add(MemoryListener *listener,
+                                        MemoryRegionSection *section)
+{
+    struct vhost_vdpa *v = container_of(listener, struct vhost_vdpa, listener);
+
+    struct vdpa_iommu *iommu;
+    Int128 end;
+    int iommu_idx;
+    IOMMUMemoryRegion *iommu_mr;
+    int ret;
+
+    if (!memory_region_is_iommu(section->mr)) {
+        return;
+    }
+
+    iommu_mr = IOMMU_MEMORY_REGION(section->mr);
+
+    iommu = g_malloc0(sizeof(*iommu));
+    end =  int128_add(int128_make64(section->offset_within_region),
+            section->size);
+    end = int128_sub(end, int128_one());
+    iommu_idx = memory_region_iommu_attrs_to_index(iommu_mr,
+            MEMTXATTRS_UNSPECIFIED);
+
+    iommu->iommu_mr = iommu_mr;
+
+    iommu_notifier_init(
+        &iommu->n, vhost_vdpa_iommu_map_notify, IOMMU_NOTIFIER_IOTLB_EVENTS,
+        section->offset_within_region, int128_get64(end), iommu_idx);
+    iommu->iommu_offset =
+        section->offset_within_address_space - section->offset_within_region;
+    iommu->dev = v;
+
+    ret = memory_region_register_iommu_notifier(section->mr, &iommu->n, NULL);
+    if (ret) {
+        g_free(iommu);
+        return;
+    }
+
+    QLIST_INSERT_HEAD(&v->iommu_list, iommu, iommu_next);
+    memory_region_iommu_replay(iommu->iommu_mr, &iommu->n);
+
+    return;
+}
+
+static void vhost_vdpa_iommu_region_del(MemoryListener *listener,
+                                        MemoryRegionSection *section)
+{
+    struct vhost_vdpa *v = container_of(listener, struct vhost_vdpa, listener);
+
+    struct vdpa_iommu *iommu;
+
+    if (!memory_region_is_iommu(section->mr)) {
+        return;
+    }
+
+    QLIST_FOREACH(iommu, &v->iommu_list, iommu_next)
+    {
+        if (MEMORY_REGION(iommu->iommu_mr) == section->mr &&
+            iommu->n.start == section->offset_within_region) {
+            memory_region_unregister_iommu_notifier(section->mr, &iommu->n);
+            QLIST_REMOVE(iommu, iommu_next);
+            g_free(iommu);
+            break;
+        }
+    }
+}
+
 static void vhost_vdpa_listener_region_add(MemoryListener *listener,
                                            MemoryRegionSection *section)
 {
@@ -186,6 +288,10 @@ static void vhost_vdpa_listener_region_add(MemoryListener *listener,
                                             v->iova_range.last)) {
         return;
     }
+    if (memory_region_is_iommu(section->mr)) {
+        vhost_vdpa_iommu_region_add(listener, section);
+        return;
+    }
 
     if (unlikely((section->offset_within_address_space & ~TARGET_PAGE_MASK) !=
                  (section->offset_within_region & ~TARGET_PAGE_MASK))) {
@@ -260,6 +366,10 @@ static void vhost_vdpa_listener_region_del(MemoryListener *listener,
                                             v->iova_range.last)) {
         return;
     }
+    if (memory_region_is_iommu(section->mr)) {
+        vhost_vdpa_iommu_region_del(listener, section);
+        return;
+    }
 
     if (unlikely((section->offset_within_address_space & ~TARGET_PAGE_MASK) !=
                  (section->offset_within_region & ~TARGET_PAGE_MASK))) {
@@ -312,6 +422,7 @@ static const MemoryListener vhost_vdpa_memory_listener = {
     .region_del = vhost_vdpa_listener_region_del,
 };
 
+
 static int vhost_vdpa_call(struct vhost_dev *dev, unsigned long int request,
                              void *arg)
 {
@@ -587,7 +698,6 @@ static int vhost_vdpa_cleanup(struct vhost_dev *dev)
     v = dev->opaque;
     trace_vhost_vdpa_cleanup(dev, v);
     vhost_vdpa_host_notifiers_uninit(dev, dev->nvqs);
-    memory_listener_unregister(&v->listener);
     vhost_vdpa_svq_cleanup(dev);
 
     dev->opaque = NULL;
@@ -1127,12 +1237,14 @@ static int vhost_vdpa_dev_start(struct vhost_dev *dev, bool started)
     }
 
     if (started) {
-        memory_listener_register(&v->listener, &address_space_memory);
+        memory_listener_register(&v->listener, dev->vdev->dma_as);
+
         return vhost_vdpa_add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK);
     } else {
         vhost_vdpa_reset_device(dev);
         vhost_vdpa_add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE |
                                    VIRTIO_CONFIG_S_DRIVER);
+
         memory_listener_unregister(&v->listener);
 
         return 0;
diff --git a/include/hw/virtio/vhost-vdpa.h b/include/hw/virtio/vhost-vdpa.h
index d10a89303e..64a46e37cb 100644
--- a/include/hw/virtio/vhost-vdpa.h
+++ b/include/hw/virtio/vhost-vdpa.h
@@ -41,8 +41,18 @@ typedef struct vhost_vdpa {
     void *shadow_vq_ops_opaque;
     struct vhost_dev *dev;
     VhostVDPAHostNotifier notifier[VIRTIO_QUEUE_MAX];
+    QLIST_HEAD(, vdpa_iommu) iommu_list;
+    IOMMUNotifier n;
 } VhostVDPA;
 
+struct vdpa_iommu {
+    struct vhost_vdpa *dev;
+    IOMMUMemoryRegion *iommu_mr;
+    hwaddr iommu_offset;
+    IOMMUNotifier n;
+    QLIST_ENTRY(vdpa_iommu) iommu_next;
+};
+
 int vhost_vdpa_dma_map(struct vhost_vdpa *v, hwaddr iova, hwaddr size,
                        void *vaddr, bool readonly);
 int vhost_vdpa_dma_unmap(struct vhost_vdpa *v, hwaddr iova, hwaddr size);
-- 
2.34.3