[PULL,02/13] qapi: nbd-export: allow select bitmaps by node/name pair

diff --git a/qapi/block-export.json b/qapi/block-export.json
index 1e34927f85e2..1de16d25899b 100644
--- a/qapi/block-export.json
+++ b/qapi/block-export.json
@@ -6,6 +6,7 @@ 
 ##

 { 'include': 'sockets.json' }
+{ 'include': 'block-core.json' }

 ##
 # @NbdServerOptions:
@@ -89,6 +90,7 @@ 
 #           @device, so the NBD client can use NBD_OPT_SET_META_CONTEXT with
 #           the metadata context name "qemu:dirty-bitmap:BITMAP" to inspect
 #           each bitmap.
+#           Since 7.1 bitmap may be specified by node/name pair.
 #
 # @allocation-depth: Also export the allocation depth map for @device, so
 #                    the NBD client can use NBD_OPT_SET_META_CONTEXT with
@@ -99,7 +101,8 @@ 
 ##
 { 'struct': 'BlockExportOptionsNbd',
   'base': 'BlockExportOptionsNbdBase',
-  'data': { '*bitmaps': ['str'], '*allocation-depth': 'bool' } }
+  'data': { '*bitmaps': ['BlockDirtyBitmapOrStr'],
+            '*allocation-depth': 'bool' } }

 ##
 # @BlockExportOptionsVhostUserBlk:
diff --git a/blockdev-nbd.c b/blockdev-nbd.c
index 9840d25a8298..7f6531cba00e 100644
--- a/blockdev-nbd.c
+++ b/blockdev-nbd.c
@@ -211,8 +211,14 @@  void qmp_nbd_server_add(NbdServerAddOptions *arg, Error **errp)
     QAPI_CLONE_MEMBERS(BlockExportOptionsNbdBase, &export_opts->u.nbd,
                        qapi_NbdServerAddOptions_base(arg));
     if (arg->has_bitmap) {
+        BlockDirtyBitmapOrStr *el = g_new(BlockDirtyBitmapOrStr, 1);
+
+        *el = (BlockDirtyBitmapOrStr) {
+            .type = QTYPE_QSTRING,
+            .u.local = g_strdup(arg->bitmap),
+        };
         export_opts->u.nbd.has_bitmaps = true;
-        QAPI_LIST_PREPEND(export_opts->u.nbd.bitmaps, g_strdup(arg->bitmap));
+        QAPI_LIST_PREPEND(export_opts->u.nbd.bitmaps, el);
     }

     /*
diff --git a/nbd/server.c b/nbd/server.c
index c5644fd3f6ad..4cdbc062c1bf 100644
--- a/nbd/server.c
+++ b/nbd/server.c
@@ -1643,7 +1643,7 @@  static int nbd_export_create(BlockExport *blk_exp, BlockExportOptions *exp_args,
     uint64_t perm, shared_perm;
     bool readonly = !exp_args->writable;
     bool shared = !exp_args->writable;
-    strList *bitmaps;
+    BlockDirtyBitmapOrStrList *bitmaps;
     size_t i;
     int ret;

@@ -1709,40 +1709,59 @@  static int nbd_export_create(BlockExport *blk_exp, BlockExportOptions *exp_args,
     }
     exp->export_bitmaps = g_new0(BdrvDirtyBitmap *, exp->nr_export_bitmaps);
     for (i = 0, bitmaps = arg->bitmaps; bitmaps;
-         i++, bitmaps = bitmaps->next) {
-        const char *bitmap = bitmaps->value;
+         i++, bitmaps = bitmaps->next)
+    {
+        const char *bitmap;
         BlockDriverState *bs = blk_bs(blk);
         BdrvDirtyBitmap *bm = NULL;

-        while (bs) {
-            bm = bdrv_find_dirty_bitmap(bs, bitmap);
-            if (bm != NULL) {
-                break;
+        switch (bitmaps->value->type) {
+        case QTYPE_QSTRING:
+            bitmap = bitmaps->value->u.local;
+            while (bs) {
+                bm = bdrv_find_dirty_bitmap(bs, bitmap);
+                if (bm != NULL) {
+                    break;
+                }
+
+                bs = bdrv_filter_or_cow_bs(bs);
             }

-            bs = bdrv_filter_or_cow_bs(bs);
-        }
+            if (bm == NULL) {
+                ret = -ENOENT;
+                error_setg(errp, "Bitmap '%s' is not found",
+                           bitmaps->value->u.local);
+                goto fail;
+            }

-        if (bm == NULL) {
-            ret = -ENOENT;
-            error_setg(errp, "Bitmap '%s' is not found", bitmap);
-            goto fail;
+            if (readonly && bdrv_is_writable(bs) &&
+                bdrv_dirty_bitmap_enabled(bm)) {
+                ret = -EINVAL;
+                error_setg(errp, "Enabled bitmap '%s' incompatible with "
+                           "readonly export", bitmap);
+                goto fail;
+            }
+            break;
+        case QTYPE_QDICT:
+            bitmap = bitmaps->value->u.external.name;
+            bm = block_dirty_bitmap_lookup(bitmaps->value->u.external.node,
+                                           bitmap, NULL, errp);
+            if (!bm) {
+                ret = -ENOENT;
+                goto fail;
+            }
+            break;
+        default:
+            abort();
         }

+        assert(bm);
+
         if (bdrv_dirty_bitmap_check(bm, BDRV_BITMAP_ALLOW_RO, errp)) {
             ret = -EINVAL;
             goto fail;
         }

-        if (readonly && bdrv_is_writable(bs) &&
-            bdrv_dirty_bitmap_enabled(bm)) {
-            ret = -EINVAL;
-            error_setg(errp,
-                       "Enabled bitmap '%s' incompatible with readonly export",
-                       bitmap);
-            goto fail;
-        }
-
         exp->export_bitmaps[i] = bm;
         assert(strlen(bitmap) <= BDRV_BITMAP_MAX_NAME_SIZE);
     }
diff --git a/qemu-nbd.c b/qemu-nbd.c
index 397ffa64d768..db63980df1e4 100644
--- a/qemu-nbd.c
+++ b/qemu-nbd.c
@@ -567,7 +567,7 @@  int main(int argc, char **argv)
     QDict *options = NULL;
     const char *export_name = NULL; /* defaults to "" later for server mode */
     const char *export_description = NULL;
-    strList *bitmaps = NULL;
+    BlockDirtyBitmapOrStrList *bitmaps = NULL;
     bool alloc_depth = false;
     const char *tlscredsid = NULL;
     const char *tlshostname = NULL;
@@ -687,7 +687,14 @@  int main(int argc, char **argv)
             alloc_depth = true;
             break;
         case 'B':
-            QAPI_LIST_PREPEND(bitmaps, g_strdup(optarg));
+            {
+                BlockDirtyBitmapOrStr *el = g_new(BlockDirtyBitmapOrStr, 1);
+                *el = (BlockDirtyBitmapOrStr) {
+                    .type = QTYPE_QSTRING,
+                    .u.local = g_strdup(optarg),
+                };
+                QAPI_LIST_PREPEND(bitmaps, el);
+            }
             break;
         case 'k':
             sockpath = optarg;