block: Decouple block device "commit all" from DriveInfo

do_commit() and mux_proc_byte() iterate over the list of drives
defined with drive_init().  This misses host block devices defined by
other means.  Such means don't exist now, but will be introduced later
in this series.

Change them to use new bdrv_commit_all(), which iterates over all host
block devices.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block.c

@@ -788,6 +788,15 @@ ro_cleanup:
     return ret;
 }
 
+void bdrv_commit_all(void)
+{
+    BlockDriverState *bs;
+
+    QTAILQ_FOREACH(bs, &bdrv_states, list) {
+        bdrv_commit(bs);
+    }
+}
+
 /*
  * Return values:
  * 0        - success

block.h

@@ -85,6 +85,7 @@ int64_t bdrv_getlength(BlockDriverState *bs);
 void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr);
 void bdrv_guess_geometry(BlockDriverState *bs, int *pcyls, int *pheads, int *psecs);
 int bdrv_commit(BlockDriverState *bs);
+void bdrv_commit_all(void);
 int bdrv_change_backing_file(BlockDriverState *bs,
     const char *backing_file, const char *backing_fmt);
 void bdrv_register(BlockDriver *bdrv);

blockdev.c

@@ -486,16 +486,16 @@ DriveInfo *drive_init(QemuOpts *opts, int default_to_scsi, int *fatal_error)
 
 void do_commit(Monitor *mon, const QDict *qdict)
 {
-    int all_devices;
-    DriveInfo *dinfo;
     const char *device = qdict_get_str(qdict, "device");
+    BlockDriverState *bs;
 
-    all_devices = !strcmp(device, "all");
+    if (!strcmp(device, "all")) {
-    QTAILQ_FOREACH(dinfo, &drives, next) {
+        bdrv_commit_all();
-        if (!all_devices)
+    } else {
-            if (strcmp(bdrv_get_device_name(dinfo->bdrv), device))
+        bs = bdrv_find(device);
-                continue;
+        if (bs) {
-        bdrv_commit(dinfo->bdrv);
+            bdrv_commit(bs);
+        }
     }
 }
 

qemu-char.c

@@ -351,12 +351,7 @@ static int mux_proc_byte(CharDriverState *chr, MuxDriver *d, int ch)
                  break;
             }
         case 's':
-            {
+            bdrv_commit_all();
-                DriveInfo *dinfo;
-                QTAILQ_FOREACH(dinfo, &drives, next) {
-                    bdrv_commit(dinfo->bdrv);
-                }
-            }
             break;
         case 'b':
             qemu_chr_event(chr, CHR_EVENT_BREAK);