[Qemu-devel] [PATCH RFC v5 2/5] virtio-iommu: Add iommu notifier for iommu-map/unmap

[Bharat Bhushan <bharat.bhushan@nxp.com>]

This patch extends VIRTIO_IOMMU_T_MAP/UNMAP request
handling to notify registered iommu-notifier. These
iommu-notifier maps the requested region in IOMMU using vfio.

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@nxp.com>
---
v4->v5:
 - Rebase to v9 version from Eric
 - PCIe device hotplug fix

 hw/virtio/trace-events           |  2 +
 hw/virtio/virtio-iommu.c         | 74 ++++++++++++++++++++++++++++++--
 include/hw/virtio/virtio-iommu.h |  6 +++
 3 files changed, 79 insertions(+), 3 deletions(-)

diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events
index 053a07b3fc..420b1e471b 100644
--- a/hw/virtio/trace-events
+++ b/hw/virtio/trace-events
@@ -72,3 +72,5 @@ virtio_iommu_translate_out(uint64_t virt_addr, uint64_t phys_addr, uint32_t sid)
 virtio_iommu_fill_resv_property(uint32_t devid, uint8_t subtype, uint64_t start, uint64_t end, uint32_t flags, size_t filled) "dev= %d, subtype=%d start=0x%"PRIx64" end=0x%"PRIx64" flags=%d filled=0x%lx"
 virtio_iommu_fill_none_property(uint32_t devid) "devid=%d"
 virtio_iommu_report_fault(uint8_t reason, uint32_t flags, uint32_t endpoint, uint64_t addr) "FAULT reason=%d flags=%d endpoint=%d address =0x%"PRIx64
+virtio_iommu_notify_map(const char *name, uint64_t iova, uint64_t paddr, uint64_t map_size) "mr=%s iova=0x%"PRIx64" pa=0x%" PRIx64" size=0x%"PRIx64""
+virtio_iommu_notify_unmap(const char *name, uint64_t iova, uint64_t map_size) "mr=%s iova=0x%"PRIx64" size=0x%"PRIx64""
diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c
index 2ec01f3b9e..613a77521d 100644
--- a/hw/virtio/virtio-iommu.c
+++ b/hw/virtio/virtio-iommu.c
@@ -99,6 +99,38 @@ static gint interval_cmp(gconstpointer a, gconstpointer b, gpointer user_data)
     }
 }
 
+static void virtio_iommu_notify_map(IOMMUMemoryRegion *mr, hwaddr iova,
+                                    hwaddr paddr, hwaddr size)
+{
+    IOMMUTLBEntry entry;
+
+    trace_virtio_iommu_notify_map(mr->parent_obj.name, iova, paddr, size);
+
+    entry.target_as = &address_space_memory;
+    entry.addr_mask = size - 1;
+    entry.iova = iova;
+    entry.perm = IOMMU_RW;
+    entry.translated_addr = paddr;
+
+    memory_region_notify_iommu(mr, 0, entry);
+}
+
+static void virtio_iommu_notify_unmap(IOMMUMemoryRegion *mr, hwaddr iova,
+                                      hwaddr size)
+{
+    IOMMUTLBEntry entry;
+
+    trace_virtio_iommu_notify_unmap(mr->parent_obj.name, iova, size);
+
+    entry.target_as = &address_space_memory;
+    entry.addr_mask = size - 1;
+    entry.iova = iova;
+    entry.perm = IOMMU_NONE;
+    entry.translated_addr = 0;
+
+    memory_region_notify_iommu(mr, 0, entry);
+}
+
 static void virtio_iommu_detach_endpoint_from_domain(viommu_endpoint *ep)
 {
     QLIST_REMOVE(ep, next);
@@ -301,9 +333,12 @@ static int virtio_iommu_map(VirtIOIOMMU *s,
     uint64_t virt_start = le64_to_cpu(req->virt_start);
     uint64_t virt_end = le64_to_cpu(req->virt_end);
     uint32_t flags = le32_to_cpu(req->flags);
+    VirtioIOMMUNotifierNode *node;
+    viommu_endpoint *ep;
     viommu_domain *domain;
     viommu_interval *interval;
     viommu_mapping *mapping;
+    uint32_t sid;
 
     interval = g_malloc0(sizeof(*interval));
 
@@ -331,9 +366,40 @@ static int virtio_iommu_map(VirtIOIOMMU *s,
 
     g_tree_insert(domain->mappings, interval, mapping);
 
+    /* All devices in an address-space share mapping */
+    QLIST_FOREACH(node, &s->notifiers_list, next) {
+        QLIST_FOREACH(ep, &domain->endpoint_list, next) {
+            sid = virtio_iommu_get_sid(node->iommu_dev);
+            if (ep->id == sid) {
+                virtio_iommu_notify_map(&node->iommu_dev->iommu_mr,
+                                        virt_start, phys_start, mapping->size);
+            }
+        }
+    }
+
     return VIRTIO_IOMMU_S_OK;
 }
 
+static void virtio_iommu_remove_mapping(VirtIOIOMMU *s, viommu_domain *domain,
+                                        viommu_interval *interval)
+{
+    VirtioIOMMUNotifierNode *node;
+    viommu_endpoint *ep;
+    uint32_t sid;
+
+    g_tree_remove(domain->mappings, (gpointer)(interval));
+    QLIST_FOREACH(node, &s->notifiers_list, next) {
+        QLIST_FOREACH(ep, &domain->endpoint_list, next) {
+            sid = virtio_iommu_get_sid(node->iommu_dev);
+            if (ep->id == sid) {
+                virtio_iommu_notify_unmap(&node->iommu_dev->iommu_mr,
+                                          interval->low,
+                                          interval->high - interval->low + 1);
+            }
+        }
+    }
+}
+
 static int virtio_iommu_unmap(VirtIOIOMMU *s,
                               struct virtio_iommu_req_unmap *req)
 {
@@ -366,18 +432,18 @@ static int virtio_iommu_unmap(VirtIOIOMMU *s,
         current.high = high;
 
         if (low == interval.low && size >= mapping->size) {
-            g_tree_remove(domain->mappings, (gpointer)(&current));
+            virtio_iommu_remove_mapping(s, domain, &current);
             interval.low = high + 1;
             trace_virtio_iommu_unmap_left_interval(current.low, current.high,
                 interval.low, interval.high);
         } else if (high == interval.high && size >= mapping->size) {
             trace_virtio_iommu_unmap_right_interval(current.low, current.high,
                 interval.low, interval.high);
-            g_tree_remove(domain->mappings, (gpointer)(&current));
+            virtio_iommu_remove_mapping(s, domain, &current);
             interval.high = low - 1;
         } else if (low > interval.low && high < interval.high) {
             trace_virtio_iommu_unmap_inc_interval(current.low, current.high);
-            g_tree_remove(domain->mappings, (gpointer)(&current));
+            virtio_iommu_remove_mapping(s, domain, &current);
         } else {
             break;
         }
@@ -907,6 +973,8 @@ static void virtio_iommu_device_realize(DeviceState *dev, Error **errp)
     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
     VirtIOIOMMU *s = VIRTIO_IOMMU(dev);
 
+    QLIST_INIT(&s->notifiers_list);
+
     virtio_init(vdev, "virtio-iommu", VIRTIO_ID_IOMMU,
                 sizeof(struct virtio_iommu_config));
 
diff --git a/include/hw/virtio/virtio-iommu.h b/include/hw/virtio/virtio-iommu.h
index 56c8b4e57f..65bda6d6fe 100644
--- a/include/hw/virtio/virtio-iommu.h
+++ b/include/hw/virtio/virtio-iommu.h
@@ -46,6 +46,11 @@ typedef struct IOMMUPciBus {
     IOMMUDevice  *pbdev[0]; /* Parent array is sparse, so dynamically alloc */
 } IOMMUPciBus;
 
+typedef struct VirtioIOMMUNotifierNode {
+    IOMMUDevice *iommu_dev;
+    QLIST_ENTRY(VirtioIOMMUNotifierNode) next;
+} VirtioIOMMUNotifierNode;
+
 typedef struct VirtIOIOMMU {
     VirtIODevice parent_obj;
     VirtQueue *req_vq;
@@ -60,6 +65,7 @@ typedef struct VirtIOIOMMU {
     QemuMutex mutex;
     GTree *endpoints;
     bool msi_bypass;
+    QLIST_HEAD(, VirtioIOMMUNotifierNode) notifiers_list;
 } VirtIOIOMMU;
 
 #endif
-- 
2.19.1