[PATCH v26 13/17] vfio: create mapped iova list when vIOMMU is enabled

[Kirti Wankhede <kwankhede@nvidia.com>]

Create mapped iova list when vIOMMU is enabled. For each mapped iova
save translated address. Add node to list on MAP and remove node from
list on UNMAP.
This list is used to track dirty pages during migration.

Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
---
 hw/vfio/common.c              | 58 ++++++++++++++++++++++++++++++++++++++-----
 include/hw/vfio/vfio-common.h |  8 ++++++
 2 files changed, 60 insertions(+), 6 deletions(-)

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index d4959c036dd1..dc56cded2d95 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -407,8 +407,8 @@ static bool vfio_listener_skipped_section(MemoryRegionSection *section)
 }
 
 /* Called with rcu_read_lock held.  */
-static bool vfio_get_vaddr(IOMMUTLBEntry *iotlb, void **vaddr,
-                           bool *read_only)
+static bool vfio_get_xlat_addr(IOMMUTLBEntry *iotlb, void **vaddr,
+                               ram_addr_t *ram_addr, bool *read_only)
 {
     MemoryRegion *mr;
     hwaddr xlat;
@@ -439,8 +439,17 @@ static bool vfio_get_vaddr(IOMMUTLBEntry *iotlb, void **vaddr,
         return false;
     }
 
-    *vaddr = memory_region_get_ram_ptr(mr) + xlat;
-    *read_only = !writable || mr->readonly;
+    if (vaddr) {
+        *vaddr = memory_region_get_ram_ptr(mr) + xlat;
+    }
+
+    if (ram_addr) {
+        *ram_addr = memory_region_get_ram_addr(mr) + xlat;
+    }
+
+    if (read_only) {
+        *read_only = !writable || mr->readonly;
+    }
 
     return true;
 }
@@ -450,7 +459,6 @@ static void vfio_iommu_map_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
     VFIOGuestIOMMU *giommu = container_of(n, VFIOGuestIOMMU, n);
     VFIOContainer *container = giommu->container;
     hwaddr iova = iotlb->iova + giommu->iommu_offset;
-    bool read_only;
     void *vaddr;
     int ret;
 
@@ -466,7 +474,10 @@ static void vfio_iommu_map_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
     rcu_read_lock();
 
     if ((iotlb->perm & IOMMU_RW) != IOMMU_NONE) {
-        if (!vfio_get_vaddr(iotlb, &vaddr, &read_only)) {
+        ram_addr_t ram_addr;
+        bool read_only;
+
+        if (!vfio_get_xlat_addr(iotlb, &vaddr, &ram_addr, &read_only)) {
             goto out;
         }
         /*
@@ -484,8 +495,28 @@ static void vfio_iommu_map_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
                          "0x%"HWADDR_PRIx", %p) = %d (%m)",
                          container, iova,
                          iotlb->addr_mask + 1, vaddr, ret);
+        } else {
+            VFIOIovaRange *iova_range;
+
+            iova_range = g_malloc0(sizeof(*iova_range));
+            iova_range->iova = iova;
+            iova_range->size = iotlb->addr_mask + 1;
+            iova_range->ram_addr = ram_addr;
+
+            QLIST_INSERT_HEAD(&giommu->iova_list, iova_range, next);
         }
     } else {
+        VFIOIovaRange *iova_range, *tmp;
+
+        QLIST_FOREACH_SAFE(iova_range, &giommu->iova_list, next, tmp) {
+            if (iova_range->iova >= iova &&
+                iova_range->iova + iova_range->size <= iova +
+                                                       iotlb->addr_mask + 1) {
+                QLIST_REMOVE(iova_range, next);
+                g_free(iova_range);
+            }
+        }
+
         ret = vfio_dma_unmap(container, iova, iotlb->addr_mask + 1);
         if (ret) {
             error_report("vfio_dma_unmap(%p, 0x%"HWADDR_PRIx", "
@@ -642,6 +673,7 @@ static void vfio_listener_region_add(MemoryListener *listener,
             g_free(giommu);
             goto fail;
         }
+        QLIST_INIT(&giommu->iova_list);
         QLIST_INSERT_HEAD(&container->giommu_list, giommu, giommu_next);
         memory_region_iommu_replay(giommu->iommu, &giommu->n);
 
@@ -740,6 +772,13 @@ static void vfio_listener_region_del(MemoryListener *listener,
         QLIST_FOREACH(giommu, &container->giommu_list, giommu_next) {
             if (MEMORY_REGION(giommu->iommu) == section->mr &&
                 giommu->n.start == section->offset_within_region) {
+                VFIOIovaRange *iova_range, *tmp;
+
+                QLIST_FOREACH_SAFE(iova_range, &giommu->iova_list, next, tmp) {
+                    QLIST_REMOVE(iova_range, next);
+                    g_free(iova_range);
+                }
+
                 memory_region_unregister_iommu_notifier(section->mr,
                                                         &giommu->n);
                 QLIST_REMOVE(giommu, giommu_next);
@@ -1541,6 +1580,13 @@ static void vfio_disconnect_container(VFIOGroup *group)
         QLIST_REMOVE(container, next);
 
         QLIST_FOREACH_SAFE(giommu, &container->giommu_list, giommu_next, tmp) {
+            VFIOIovaRange *iova_range, *itmp;
+
+            QLIST_FOREACH_SAFE(iova_range, &giommu->iova_list, next, itmp) {
+                QLIST_REMOVE(iova_range, next);
+                g_free(iova_range);
+            }
+
             memory_region_unregister_iommu_notifier(
                     MEMORY_REGION(giommu->iommu), &giommu->n);
             QLIST_REMOVE(giommu, giommu_next);
diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
index 0a1651eda2d0..aa7524fe2cc5 100644
--- a/include/hw/vfio/vfio-common.h
+++ b/include/hw/vfio/vfio-common.h
@@ -89,11 +89,19 @@ typedef struct VFIOContainer {
     QLIST_ENTRY(VFIOContainer) next;
 } VFIOContainer;
 
+typedef struct VFIOIovaRange {
+    hwaddr iova;
+    size_t size;
+    ram_addr_t ram_addr;
+    QLIST_ENTRY(VFIOIovaRange) next;
+} VFIOIovaRange;
+
 typedef struct VFIOGuestIOMMU {
     VFIOContainer *container;
     IOMMUMemoryRegion *iommu;
     hwaddr iommu_offset;
     IOMMUNotifier n;
+    QLIST_HEAD(, VFIOIovaRange) iova_list;
     QLIST_ENTRY(VFIOGuestIOMMU) giommu_next;
 } VFIOGuestIOMMU;
 
-- 
2.7.0