numa: Keep track of NUMA nodes present on the command-line

Based on "enable sparse node numbering" patch from Nishanth Aravamudan,
but without the code to actually support sparse node IDs. This just adds
the code to keep track of present/non-present nodes on the command-line,
without changing any behavior.

Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
[Rename max_numa_node to max_numa_nodeid -Eduardo]
[Initialize max_numa_nodeid to 0 -Eduardo]
[Use MAX() macro when setting max_numa_nodeid -Eduardo]
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Hu Tao <hutao@cn.fujitsu.com>
Reviewed-by: Eric Blake <eblake@redhat.com>

include/sysemu/sysemu.h

@@ -146,11 +146,16 @@ extern int mem_prealloc;
  */
 #define MAX_CPUMASK_BITS 255
 
-extern int nb_numa_nodes;
+extern int nb_numa_nodes;   /* Number of NUMA nodes */
+extern int max_numa_nodeid; /* Highest specified NUMA node ID, plus one.
+                             * For all nodes, nodeid < max_numa_nodeid
+                             */
+
 typedef struct node_info {
     uint64_t node_mem;
     DECLARE_BITMAP(node_cpu, MAX_CPUMASK_BITS);
     struct HostMemoryBackend *node_memdev;
+    bool present;
 } NodeInfo;
 extern NodeInfo numa_info[MAX_NODES];
 void set_numa_nodes(void);

numa.c

@@ -106,6 +106,8 @@ static void numa_node_parse(NumaNodeOptions *node, QemuOpts *opts, Error **errp)
         numa_info[nodenr].node_mem = object_property_get_int(o, "size", NULL);
         numa_info[nodenr].node_memdev = MEMORY_BACKEND(o);
     }
+    numa_info[nodenr].present = true;
+    max_numa_nodeid = MAX(max_numa_nodeid, nodenr + 1);
 }
 
 int numa_init_func(QemuOpts *opts, void *opaque)

vl.c

@@ -196,6 +196,7 @@ static QTAILQ_HEAD(, FWBootEntry) fw_boot_order =
     QTAILQ_HEAD_INITIALIZER(fw_boot_order);
 
 int nb_numa_nodes;
+int max_numa_nodeid;
 NodeInfo numa_info[MAX_NODES];
 
 uint8_t qemu_uuid[16];
@@ -2984,10 +2985,12 @@ int main(int argc, char **argv, char **envp)
 
     for (i = 0; i < MAX_NODES; i++) {
         numa_info[i].node_mem = 0;
+        numa_info[i].present = false;
         bitmap_zero(numa_info[i].node_cpu, MAX_CPUMASK_BITS);
     }
 
     nb_numa_nodes = 0;
+    max_numa_nodeid = 0;
     nb_nics = 0;
 
     bdrv_init_with_whitelist();