[PATCH v7 7/9] memory: Add Error** argument to memory_get_xlat_addr()

["Cédric Le Goater" <clg@redhat.com>]

Let the callers do the reporting. This will be useful in
vfio_iommu_map_dirty_notify().

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: David Hildenbrand <david@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
---
 include/exec/memory.h  | 15 ++++++++++++++-
 hw/vfio/common.c       | 13 +++++++++----
 hw/virtio/vhost-vdpa.c |  5 ++++-
 system/memory.c        | 10 +++++-----
 4 files changed, 32 insertions(+), 11 deletions(-)

diff --git a/include/exec/memory.h b/include/exec/memory.h
index d417d7f363dbbca6553c449582a93d5da73cca40..9cdd64e9c69b63f9d27cebc2e8cb366e22ed7577 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -774,9 +774,22 @@ void ram_discard_manager_register_listener(RamDiscardManager *rdm,
 void ram_discard_manager_unregister_listener(RamDiscardManager *rdm,
                                              RamDiscardListener *rdl);
 
+/**
+ * memory_get_xlat_addr: Extract addresses from a TLB entry
+ *
+ * @iotlb: pointer to an #IOMMUTLBEntry
+ * @vaddr: virtual address
+ * @ram_addr: RAM address
+ * @read_only: indicates if writes are allowed
+ * @mr_has_discard_manager: indicates memory is controlled by a
+ *                          RamDiscardManager
+ * @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);
+                          bool *mr_has_discard_manager, Error **errp);
 
 typedef struct CoalescedMemoryRange CoalescedMemoryRange;
 typedef struct MemoryRegionIoeventfd MemoryRegionIoeventfd;
diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index c7f274fb5c851e4c44498552891265018d2c5313..7313043f1d161ed0326b5ba3fa1085608eaf6740 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -253,12 +253,13 @@ 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)
+                               ram_addr_t *ram_addr, bool *read_only,
+                               Error **errp)
 {
     bool ret, mr_has_discard_manager;
 
     ret = memory_get_xlat_addr(iotlb, vaddr, ram_addr, read_only,
-                               &mr_has_discard_manager);
+                               &mr_has_discard_manager, errp);
     if (ret && mr_has_discard_manager) {
         /*
          * Malicious VMs might trigger discarding of IOMMU-mapped memory. The
@@ -288,6 +289,7 @@ static void vfio_iommu_map_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
     hwaddr iova = iotlb->iova + giommu->iommu_offset;
     void *vaddr;
     int ret;
+    Error *local_err = NULL;
 
     trace_vfio_iommu_map_notify(iotlb->perm == IOMMU_NONE ? "UNMAP" : "MAP",
                                 iova, iova + iotlb->addr_mask);
@@ -304,7 +306,8 @@ 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)) {
+        if (!vfio_get_xlat_addr(iotlb, &vaddr, NULL, &read_only, &local_err)) {
+            error_report_err(local_err);
             goto out;
         }
         /*
@@ -1213,6 +1216,7 @@ static void vfio_iommu_map_dirty_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
     VFIOContainerBase *bcontainer = giommu->bcontainer;
     hwaddr iova = iotlb->iova + giommu->iommu_offset;
     ram_addr_t translated_addr;
+    Error *local_err = NULL;
     int ret = -EINVAL;
 
     trace_vfio_iommu_map_dirty_notify(iova, iova + iotlb->addr_mask);
@@ -1224,7 +1228,8 @@ static void vfio_iommu_map_dirty_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
     }
 
     rcu_read_lock();
-    if (!vfio_get_xlat_addr(iotlb, NULL, &translated_addr, NULL)) {
+    if (!vfio_get_xlat_addr(iotlb, NULL, &translated_addr, 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 e827b9175fc61f1ef419e48d90a440b00449312a..ed99ab87457d8f31b98ace960713f48d47b27102 100644
--- a/hw/virtio/vhost-vdpa.c
+++ b/hw/virtio/vhost-vdpa.c
@@ -208,6 +208,7 @@ static void vhost_vdpa_iommu_map_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb)
     void *vaddr;
     int ret;
     Int128 llend;
+    Error *local_err = NULL;
 
     if (iotlb->target_as != &address_space_memory) {
         error_report("Wrong target AS \"%s\", only system memory is allowed",
@@ -227,7 +228,9 @@ 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,
+                                  &local_err)) {
+            error_report_err(local_err);
             return;
         }
         ret = vhost_vdpa_dma_map(s, VHOST_VDPA_GUEST_PA_ASID, iova,
diff --git a/system/memory.c b/system/memory.c
index 642a449f8c867d38c62a748a4dfd5c055637c205..9540caa8a1f4da8501bf5ae9d7eedde8b775e1dc 100644
--- a/system/memory.c
+++ b/system/memory.c
@@ -2179,7 +2179,7 @@ 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)
+                          bool *mr_has_discard_manager, Error **errp)
 {
     MemoryRegion *mr;
     hwaddr xlat;
@@ -2197,7 +2197,7 @@ bool memory_get_xlat_addr(IOMMUTLBEntry *iotlb, void **vaddr,
     mr = address_space_translate(&address_space_memory, iotlb->translated_addr,
                                  &xlat, &len, writable, MEMTXATTRS_UNSPECIFIED);
     if (!memory_region_is_ram(mr)) {
-        error_report("iommu map to non memory area %" HWADDR_PRIx "", xlat);
+        error_setg(errp, "iommu map to non memory area %" HWADDR_PRIx "", xlat);
         return false;
     } else if (memory_region_has_ram_discard_manager(mr)) {
         RamDiscardManager *rdm = memory_region_get_ram_discard_manager(mr);
@@ -2216,8 +2216,8 @@ bool memory_get_xlat_addr(IOMMUTLBEntry *iotlb, void **vaddr,
          * were already restored before IOMMUs are restored.
          */
         if (!ram_discard_manager_is_populated(rdm, &tmp)) {
-            error_report("iommu map to discarded memory (e.g., unplugged via"
-                         " virtio-mem): %" HWADDR_PRIx "",
+            error_setg(errp, "iommu map to discarded memory (e.g., unplugged"
+                         " via virtio-mem): %" HWADDR_PRIx "",
                          iotlb->translated_addr);
             return false;
         }
@@ -2228,7 +2228,7 @@ bool memory_get_xlat_addr(IOMMUTLBEntry *iotlb, void **vaddr,
      * check that it did not truncate too much.
      */
     if (len & iotlb->addr_mask) {
-        error_report("iommu has granularity incompatible with target AS");
+        error_setg(errp, "iommu has granularity incompatible with target AS");
         return false;
     }
 
-- 
2.45.0