[PATCH v16 05/10] 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>
Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>

---

v11 -> v12:
- Added Jean's R-b
- s/qemu_log_mask/error_report_once

v10 -> v11:
- take into account the new value struct and use
  g_tree_lookup_extended
- switched to error_report_once

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 | 60 +++++++++++++++++++++++++++++++++++++++-
 2 files changed, 60 insertions(+), 1 deletion(-)

diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events
index 22162d6583..095aa8b509 100644
--- a/hw/virtio/trace-events
+++ b/hw/virtio/trace-events
@@ -71,3 +71,4 @@ virtio_iommu_get_endpoint(uint32_t ep_id) "Alloc endpoint=%d"
 virtio_iommu_put_endpoint(uint32_t ep_id) "Free endpoint=%d"
 virtio_iommu_get_domain(uint32_t domain_id) "Alloc domain=%d"
 virtio_iommu_put_domain(uint32_t domain_id) "Free domain=%d"
+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 844d34c270..59e9cd3d9a 100644
--- a/hw/virtio/virtio-iommu.c
+++ b/hw/virtio/virtio-iommu.c
@@ -473,19 +473,77 @@ static IOMMUTLBEntry virtio_iommu_translate(IOMMUMemoryRegion *mr, hwaddr addr,
                                             int iommu_idx)
 {
     IOMMUDevice *sdev = container_of(mr, IOMMUDevice, iommu_mr);
+    VirtIOIOMMUInterval interval, *mapping_key;
+    VirtIOIOMMUMapping *mapping_value;
+    VirtIOIOMMU *s = sdev->viommu;
+    VirtIOIOMMUEndpoint *ep;
+    bool bypass_allowed;
     uint32_t sid;
+    bool found;
+
+    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_vdev_has_feature(&s->parent_obj,
+                                             VIRTIO_IOMMU_F_BYPASS);
+
     sid = virtio_iommu_get_bdf(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_once("%s sid=%d is not known!!", __func__, sid);
+        } else {
+            entry.perm = flag;
+        }
+        goto unlock;
+    }
+
+    if (!ep->domain) {
+        if (!bypass_allowed) {
+            error_report_once("%s %02x:%02x.%01x not attached to any domain",
+                              __func__, PCI_BUS_NUM(sid),
+                              PCI_SLOT(sid), PCI_FUNC(sid));
+        } else {
+            entry.perm = flag;
+        }
+        goto unlock;
+    }
+
+    found = g_tree_lookup_extended(ep->domain->mappings, (gpointer)(&interval),
+                                   (void **)&mapping_key,
+                                   (void **)&mapping_value);
+    if (!found) {
+        error_report_once("%s no mapping for 0x%"PRIx64" for sid=%d",
+                          __func__, addr, sid);
+        goto unlock;
+    }
+
+    if (((flag & IOMMU_RO) &&
+            !(mapping_value->flags & VIRTIO_IOMMU_MAP_F_READ)) ||
+        ((flag & IOMMU_WO) &&
+            !(mapping_value->flags & VIRTIO_IOMMU_MAP_F_WRITE))) {
+        error_report_once("%s permission error on 0x%"PRIx64"(%d): allowed=%d",
+                          __func__, addr, flag, mapping_value->flags);
+        goto unlock;
+    }
+    entry.translated_addr = addr - mapping_key->low + mapping_value->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