hw/block/fdc: Implement tray status

The tray of an FDD is open iff there is no medium inserted (there are
only two states for an FDD: "medium inserted" or "no medium inserted").
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

hw/block/fdc.c

@@ -192,6 +192,8 @@ typedef struct FDrive {
     uint8_t ro;               /* Is read-only           */
     uint8_t media_changed;    /* Is media changed       */
     uint8_t media_rate;       /* Data rate of medium    */
+
+    bool media_inserted;      /* Is there a medium in the tray */
 } FDrive;
 
 static void fd_init(FDrive *drv)
@@ -261,7 +263,7 @@ static int fd_seek(FDrive *drv, uint8_t head, uint8_t track, uint8_t sect,
 #endif
         drv->head = head;
         if (drv->track != track) {
-            if (drv->blk != NULL && blk_is_inserted(drv->blk)) {
+            if (drv->media_inserted) {
                 drv->media_changed = 0;
             }
             ret = 1;
@@ -270,7 +272,7 @@ static int fd_seek(FDrive *drv, uint8_t head, uint8_t track, uint8_t sect,
         drv->sect = sect;
     }
 
-    if (drv->blk == NULL || !blk_is_inserted(drv->blk)) {
+    if (!drv->media_inserted) {
         ret = 2;
     }
 
@@ -296,7 +298,7 @@ static void fd_revalidate(FDrive *drv)
         ro = blk_is_read_only(drv->blk);
         pick_geometry(drv->blk, &nb_heads, &max_track,
                       &last_sect, drv->drive, &drive, &rate);
-        if (!blk_is_inserted(drv->blk)) {
+        if (!drv->media_inserted) {
             FLOPPY_DPRINTF("No disk in drive\n");
         } else {
             FLOPPY_DPRINTF("Floppy disk (%d h %d t %d s) %s\n", nb_heads,
@@ -692,7 +694,7 @@ static bool fdrive_media_changed_needed(void *opaque)
 {
     FDrive *drive = opaque;
 
-    return (drive->blk != NULL && drive->media_changed != 1);
+    return (drive->media_inserted && drive->media_changed != 1);
 }
 
 static const VMStateDescription vmstate_fdrive_media_changed = {
@@ -2184,12 +2186,21 @@ static void fdctrl_change_cb(void *opaque, bool load)
 {
     FDrive *drive = opaque;
 
+    drive->media_inserted = load && drive->blk && blk_is_inserted(drive->blk);
+
     drive->media_changed = 1;
     fd_revalidate(drive);
 }
 
+static bool fdctrl_is_tray_open(void *opaque)
+{
+    FDrive *drive = opaque;
+    return !drive->media_inserted;
+}
+
 static const BlockDevOps fdctrl_block_ops = {
     .change_media_cb = fdctrl_change_cb,
+    .is_tray_open = fdctrl_is_tray_open,
 };
 
 /* Init functions */
@@ -2217,6 +2228,7 @@ static void fdctrl_connect_drives(FDCtrl *fdctrl, Error **errp)
         fdctrl_change_cb(drive, 0);
         if (drive->blk) {
             blk_set_dev_ops(drive->blk, &fdctrl_block_ops, drive);
+            drive->media_inserted = blk_is_inserted(drive->blk);
         }
     }
 }

tests/fdc-test.c

@@ -304,9 +304,7 @@ static void test_media_insert(void)
     qmp_discard_response("{'execute':'change', 'arguments':{"
                          " 'device':'floppy0', 'target': %s, 'arg': 'raw' }}",
                          test_image);
-    qmp_discard_response(""); /* ignore event
-                                 (FIXME open -> open transition?!) */
-    qmp_discard_response(""); /* ignore event */
+    qmp_discard_response(""); /* ignore event (open -> close) */
 
     dir = inb(FLOPPY_BASE + reg_dir);
     assert_bit_set(dir, DSKCHG);