qemu: blockstats: Switch to caller allocated hash table

Allocate the hash table in the monitor wrapper function instead of the
worker itself so that the text monitor impl that will be added in the
next patch doesn't have to duplicate it.

src/qemu/qemu_monitor.c

@@ -1864,7 +1864,18 @@ qemuMonitorGetAllBlockStatsInfo(qemuMonitorPtr mon,
         return -1;
     }
 
-    return qemuMonitorJSONGetAllBlockStatsInfo(mon, ret_stats, backingChain);
+    if (!(*ret_stats = virHashCreate(10, virHashValueFree)))
+        goto error;
+
+    if (qemuMonitorJSONGetAllBlockStatsInfo(mon, *ret_stats, backingChain) < 0)
+        goto error;
+
+    return 0;
+
+ error:
+    virHashFree(*ret_stats);
+    *ret_stats = NULL;
+    return -1;
 }
 
 

src/qemu/qemu_monitor_json.c

@@ -1695,7 +1695,10 @@ int qemuMonitorJSONGetBlockStatsInfo(qemuMonitorPtr mon,
     if (flush_total_times)
         *flush_total_times = -1;
 
-    if (qemuMonitorJSONGetAllBlockStatsInfo(mon, &blockstats, false) < 0)
+    if (!(blockstats = virHashCreate(10, virHashValueFree)))
+        goto cleanup;
+
+    if (qemuMonitorJSONGetAllBlockStatsInfo(mon, blockstats, false) < 0)
         goto cleanup;
 
     if (!(stats = virHashLookup(blockstats, dev_name))) {
@@ -1870,7 +1873,7 @@ qemuMonitorJSONGetOneBlockStatsInfo(virJSONValuePtr dev,
 
 int
 qemuMonitorJSONGetAllBlockStatsInfo(qemuMonitorPtr mon,
-                                    virHashTablePtr *ret_stats,
+                                    virHashTablePtr hash,
                                     bool backingChain)
 {
     int ret = -1;
@@ -1879,14 +1882,10 @@ qemuMonitorJSONGetAllBlockStatsInfo(qemuMonitorPtr mon,
     virJSONValuePtr cmd;
     virJSONValuePtr reply = NULL;
     virJSONValuePtr devices;
-    virHashTablePtr hash = NULL;
 
     if (!(cmd = qemuMonitorJSONMakeCommand("query-blockstats", NULL)))
         return -1;
 
-    if (!(hash = virHashCreate(10, virHashValueFree)))
-        goto cleanup;
-
     if ((rc = qemuMonitorJSONCommand(mon, cmd, &reply)) < 0)
         goto cleanup;
 
@@ -1924,12 +1923,9 @@ qemuMonitorJSONGetAllBlockStatsInfo(qemuMonitorPtr mon,
 
     }
 
-    *ret_stats = hash;
-    hash = NULL;
     ret = 0;
 
  cleanup:
-    virHashFree(hash);
     virJSONValueFree(cmd);
     virJSONValueFree(reply);
     return ret;

src/qemu/qemu_monitor_json.h

@@ -82,7 +82,7 @@ int qemuMonitorJSONGetBlockStatsInfo(qemuMonitorPtr mon,
                                      long long *flush_req,
                                      long long *flush_total_times);
 int qemuMonitorJSONGetAllBlockStatsInfo(qemuMonitorPtr mon,
-                                        virHashTablePtr *ret_stats,
+                                        virHashTablePtr hash,
                                         bool backingChain);
 int qemuMonitorJSONBlockStatsUpdateCapacity(qemuMonitorPtr mon,
                                             virHashTablePtr stats,