[Qemu-devel] [PATCH for-4.2 v10 09/15] virtio-iommu: Implement translate

[Eric Auger <eric.auger@redhat.com>]

This patch implements the translate callback

Signed-off-by: Eric Auger <eric.auger@redhat.com>

---
v6 -> v7:
- implemented bypass-mode

v5 -> v6:
- replace error_report by qemu_log_mask

v4 -> v5:
- check the device domain is not NULL
- s/printf/error_report
- set flags to IOMMU_NONE in case of all translation faults
---
 hw/virtio/trace-events   |  1 +
 hw/virtio/virtio-iommu.c | 58 +++++++++++++++++++++++++++++++++++++++-
 2 files changed, 58 insertions(+), 1 deletion(-)

diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events
index 25a71b0505..8257065159 100644
--- a/hw/virtio/trace-events
+++ b/hw/virtio/trace-events
@@ -74,3 +74,4 @@ virtio_iommu_put_domain(uint32_t domain_id) "Free domain=%d"
 virtio_iommu_unmap_left_interval(uint64_t low, uint64_t high, uint64_t next_low, uint64_t next_high) "Unmap left [0x%"PRIx64",0x%"PRIx64"], new interval=[0x%"PRIx64",0x%"PRIx64"]"
 virtio_iommu_unmap_right_interval(uint64_t low, uint64_t high, uint64_t next_low, uint64_t next_high) "Unmap right [0x%"PRIx64",0x%"PRIx64"], new interval=[0x%"PRIx64",0x%"PRIx64"]"
 virtio_iommu_unmap_inc_interval(uint64_t low, uint64_t high) "Unmap inc [0x%"PRIx64",0x%"PRIx64"]"
+virtio_iommu_translate_out(uint64_t virt_addr, uint64_t phys_addr, uint32_t sid) "0x%"PRIx64" -> 0x%"PRIx64 " for sid=%d"
diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c
index 4706b9da6e..a8de583f9a 100644
--- a/hw/virtio/virtio-iommu.c
+++ b/hw/virtio/virtio-iommu.c
@@ -464,19 +464,75 @@ static IOMMUTLBEntry virtio_iommu_translate(IOMMUMemoryRegion *mr, hwaddr addr,
                                             int iommu_idx)
 {
     IOMMUDevice *sdev = container_of(mr, IOMMUDevice, iommu_mr);
+    VirtIOIOMMU *s = sdev->viommu;
     uint32_t sid;
+    viommu_endpoint *ep;
+    viommu_mapping *mapping;
+    viommu_interval interval;
+    bool bypass_allowed;
+
+    interval.low = addr;
+    interval.high = addr + 1;
 
     IOMMUTLBEntry entry = {
         .target_as = &address_space_memory,
         .iova = addr,
         .translated_addr = addr,
-        .addr_mask = ~(hwaddr)0,
+        .addr_mask = (1 << ctz32(s->config.page_size_mask)) - 1,
         .perm = IOMMU_NONE,
     };
 
+    bypass_allowed = virtio_has_feature(s->acked_features,
+                                        VIRTIO_IOMMU_F_BYPASS);
+
     sid = virtio_iommu_get_sid(sdev);
 
     trace_virtio_iommu_translate(mr->parent_obj.name, sid, addr, flag);
+    qemu_mutex_lock(&s->mutex);
+
+    ep = g_tree_lookup(s->endpoints, GUINT_TO_POINTER(sid));
+    if (!ep) {
+        if (!bypass_allowed) {
+            error_report("%s sid=%d is not known!!", __func__, sid);
+        } else {
+            entry.perm = flag;
+        }
+        goto unlock;
+    }
+
+    if (!ep->domain) {
+        if (!bypass_allowed) {
+            qemu_log_mask(LOG_GUEST_ERROR,
+                          "%s %02x:%02x.%01x not attached to any domain\n",
+                          __func__, PCI_BUS_NUM(sid),
+                          PCI_SLOT(sid), PCI_FUNC(sid));
+        } else {
+            entry.perm = flag;
+        }
+        goto unlock;
+    }
+
+    mapping = g_tree_lookup(ep->domain->mappings, (gpointer)(&interval));
+    if (!mapping) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s no mapping for 0x%"PRIx64" for sid=%d\n",
+                      __func__, addr, sid);
+        goto unlock;
+    }
+
+    if (((flag & IOMMU_RO) && !(mapping->flags & VIRTIO_IOMMU_MAP_F_READ)) ||
+        ((flag & IOMMU_WO) && !(mapping->flags & VIRTIO_IOMMU_MAP_F_WRITE))) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "Permission error on 0x%"PRIx64"(%d): allowed=%d\n",
+                      addr, flag, mapping->flags);
+        goto unlock;
+    }
+    entry.translated_addr = addr - mapping->virt_addr + mapping->phys_addr;
+    entry.perm = flag;
+    trace_virtio_iommu_translate_out(addr, entry.translated_addr, sid);
+
+unlock:
+    qemu_mutex_unlock(&s->mutex);
     return entry;
 }
 
-- 
2.20.1