[Qemu-devel] [PATCH v2 2/2] fdc: fix media detection

[Pavel Hrdina <phrdina@redhat.com>]

We have to set up 'media_changed' after guest start so floppy driver
could detect that there is no media in drive. For this purpose we call
'fdctrl_change_cb' instead of 'fd_revalidate' in 'fdctrl_connect_drives'.
'fd_revalidate' is called inside 'fdctrl_change_cb'.

We still have to set default drive geometry in 'fd_revalidate' even
if there is no media in drive. When you try to open (windows) or mount (linux)
floppy the driver tries to seek on track 1. Linux guest hang in loop than crash
and windows guest print error message.

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
---
 hw/fdc.c |   14 ++++++++------
 1 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/hw/fdc.c b/hw/fdc.c
index cb4cd25..b1bc6ed 100644
--- a/hw/fdc.c
+++ b/hw/fdc.c
@@ -179,12 +179,14 @@ static void fd_revalidate(FDrive *drv)
     FDriveRate rate;
 
     FLOPPY_DPRINTF("revalidate\n");
-    if (drv->bs != NULL && bdrv_is_inserted(drv->bs)) {
+    if (drv->bs != NULL) {
         ro = bdrv_is_read_only(drv->bs);
         bdrv_get_floppy_geometry_hint(drv->bs, &nb_heads, &max_track,
                                       &last_sect, drv->drive, &drive, &rate);
-        if (nb_heads != 0 && max_track != 0 && last_sect != 0) {
-            FLOPPY_DPRINTF("User defined disk (%d %d %d)",
+        if (!bdrv_is_inserted(drv->bs)) {
+            FLOPPY_DPRINTF("No disk in drive\n");
+        } else if (nb_heads != 0 && max_track != 0 && last_sect != 0) {
+            FLOPPY_DPRINTF("User defined disk (%d %d %d)\n",
                            nb_heads - 1, max_track, last_sect);
         } else {
             FLOPPY_DPRINTF("Floppy disk (%d h %d t %d s) %s\n", nb_heads,
@@ -201,7 +203,7 @@ static void fd_revalidate(FDrive *drv)
         drv->drive = drive;
         drv->media_rate = rate;
     } else {
-        FLOPPY_DPRINTF("No disk in drive\n");
+        FLOPPY_DPRINTF("Invalid disk in drive\n");
         drv->last_sect = 0;
         drv->max_track = 0;
         drv->flags &= ~FDISK_DBL_SIDES;
@@ -709,7 +711,7 @@ static void fdctrl_raise_irq(FDCtrl *fdctrl, uint8_t status0)
         FDrive *cur_drv;
         /* A seek clears the disk change line (if a disk is inserted) */
         cur_drv = get_cur_drv(fdctrl);
-        if (cur_drv->max_track) {
+        if (cur_drv->bs != NULL && bdrv_is_inserted(cur_drv->bs)) {
             cur_drv->media_changed = 0;
         }
     }
@@ -1878,7 +1880,7 @@ static int fdctrl_connect_drives(FDCtrl *fdctrl)
         }
 
         fd_init(drive);
-        fd_revalidate(drive);
+        fdctrl_change_cb(drive, 0);
         if (drive->bs) {
             bdrv_set_dev_ops(drive->bs, &fdctrl_block_ops, drive);
         }
-- 
1.7.7.6