[PATCH V1 16/26] vfio: return mr from vfio_get_xlat_addr

[Steve Sistare <steven.sistare@oracle.com>]

Return the memory region that the translated address is found in, for
use in a subsequent patch.  No functional change.

Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
---
 hw/vfio/common.c       | 9 ++++++---
 hw/virtio/vhost-vdpa.c | 2 +-
 include/exec/memory.h  | 5 ++++-
 system/memory.c        | 8 +++++++-
 4 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index db0498e..4bbc29f 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -248,12 +248,13 @@ static bool vfio_listener_skipped_section(MemoryRegionSection *section)
 /* Called with rcu_read_lock held.  */
 static bool vfio_get_xlat_addr(IOMMUTLBEntry *iotlb, void **vaddr,
                                ram_addr_t *ram_addr, bool *read_only,
+                               MemoryRegion **mr_p,
                                Error **errp)
 {
     bool ret, mr_has_discard_manager;
 
     ret = memory_get_xlat_addr(iotlb, vaddr, ram_addr, read_only,
-                               &mr_has_discard_manager, errp);
+                               &mr_has_discard_manager, mr_p, errp);
     if (ret && mr_has_discard_manager) {
         /*
          * Malicious VMs might trigger discarding of IOMMU-mapped memory. The
@@ -300,7 +301,8 @@ static void vfio_iommu_map_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
     if ((iotlb->perm & IOMMU_RW) != IOMMU_NONE) {
         bool read_only;
 
-        if (!vfio_get_xlat_addr(iotlb, &vaddr, NULL, &read_only, &local_err)) {
+        if (!vfio_get_xlat_addr(iotlb, &vaddr, NULL, &read_only, NULL,
+                                &local_err)) {
             error_report_err(local_err);
             goto out;
         }
@@ -1279,7 +1281,8 @@ static void vfio_iommu_map_dirty_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
     }
 
     rcu_read_lock();
-    if (!vfio_get_xlat_addr(iotlb, NULL, &translated_addr, NULL, &local_err)) {
+    if (!vfio_get_xlat_addr(iotlb, NULL, &translated_addr, NULL, NULL,
+                            &local_err)) {
         error_report_err(local_err);
         goto out_unlock;
     }
diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
index 3cdaa12..a1866bb 100644
--- a/hw/virtio/vhost-vdpa.c
+++ b/hw/virtio/vhost-vdpa.c
@@ -228,7 +228,7 @@ static void vhost_vdpa_iommu_map_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
     if ((iotlb->perm & IOMMU_RW) != IOMMU_NONE) {
         bool read_only;
 
-        if (!memory_get_xlat_addr(iotlb, &vaddr, NULL, &read_only, NULL,
+        if (!memory_get_xlat_addr(iotlb, &vaddr, NULL, &read_only, NULL, NULL,
                                   &local_err)) {
             error_report_err(local_err);
             return;
diff --git a/include/exec/memory.h b/include/exec/memory.h
index ea5d33a..a2f1229 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -747,13 +747,16 @@ void ram_discard_manager_unregister_listener(RamDiscardManager *rdm,
  * @read_only: indicates if writes are allowed
  * @mr_has_discard_manager: indicates memory is controlled by a
  *                          RamDiscardManager
+ * @mr_p: return the MemoryRegion containing the @iotlb translated addr
  * @errp: pointer to Error*, to store an error if it happens.
  *
  * Return: true on success, else false setting @errp with error.
  */
 bool memory_get_xlat_addr(IOMMUTLBEntry *iotlb, void **vaddr,
                           ram_addr_t *ram_addr, bool *read_only,
-                          bool *mr_has_discard_manager, Error **errp);
+                          bool *mr_has_discard_manager,
+                          MemoryRegion **mr_p,
+                          Error **errp);
 
 typedef struct CoalescedMemoryRange CoalescedMemoryRange;
 typedef struct MemoryRegionIoeventfd MemoryRegionIoeventfd;
diff --git a/system/memory.c b/system/memory.c
index 4c82979..4ec2b8f 100644
--- a/system/memory.c
+++ b/system/memory.c
@@ -2185,7 +2185,9 @@ void ram_discard_manager_unregister_listener(RamDiscardManager *rdm,
 /* Called with rcu_read_lock held.  */
 bool memory_get_xlat_addr(IOMMUTLBEntry *iotlb, void **vaddr,
                           ram_addr_t *ram_addr, bool *read_only,
-                          bool *mr_has_discard_manager, Error **errp)
+                          bool *mr_has_discard_manager,
+                          MemoryRegion **mr_p,
+                          Error **errp)
 {
     MemoryRegion *mr;
     hwaddr xlat;
@@ -2250,6 +2252,10 @@ bool memory_get_xlat_addr(IOMMUTLBEntry *iotlb, void **vaddr,
         *read_only = !writable || mr->readonly;
     }
 
+    if (mr_p) {
+        *mr_p = mr;
+    }
+
     return true;
 }
 
-- 
1.8.3.1