On 01/27/2016 07:38 AM, Paolo Bonzini wrote:
>
>
> On 25/01/2016 20:41, John Snow wrote:
>> Split apart pick_geometry by creating a pick_drive routine that will only
>> ever called during device bring-up instead of relying on pick_geometry to
>> be used in both cases.
>>
>> With this change, the drive field is changed to be 'write once'. It is
>> not altered after the initialization routines exit.
>>
>> media_validated does not need to be migrated. The target VM
>> will just revalidate the media on post_load anyway.
>>
>> Reviewed-by: Eric Blake <ebl...@redhat.com>
>> Signed-off-by: John Snow <js...@redhat.com>
>> Message-id: 1453495865-9649-7-git-send-email-js...@redhat.com
>
> Sorry, this breaks the RHEL6.5 Linux installer CD. It just hangs at
> floppy detection and finally panics.
>
> Paolo
>
Crap, alright. I'll get right to it. That's what I get for poking a
hibernating bear.
>> ---
>> hw/block/fdc.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++----------
>> 1 file changed, 46 insertions(+), 10 deletions(-)
>>
>> diff --git a/hw/block/fdc.c b/hw/block/fdc.c
>> index a8f0cf2..f8e070e 100644
>> --- a/hw/block/fdc.c
>> +++ b/hw/block/fdc.c
>> @@ -151,6 +151,7 @@ typedef struct FDrive {
>> uint8_t media_rate; /* Data rate of medium */
>>
>> bool media_inserted; /* Is there a medium in the tray */
>> + bool media_validated; /* Have we validated the media? */
>> } FDrive;
>>
>> static void fd_init(FDrive *drv)
>> @@ -162,6 +163,8 @@ static void fd_init(FDrive *drv)
>> drv->disk = FLOPPY_DRIVE_TYPE_NONE;
>> drv->last_sect = 0;
>> drv->max_track = 0;
>> + drv->ro = true;
>> + drv->media_changed = 1;
>> }
>>
>> #define NUM_SIDES(drv) ((drv)->flags & FDISK_DBL_SIDES ? 2 : 1)
>> @@ -244,13 +247,24 @@ static void fd_recalibrate(FDrive *drv)
>> fd_seek(drv, 0, 0, 1, 1);
>> }
>>
>> -static void pick_geometry(FDrive *drv)
>> +/**
>> + * Determine geometry based on inserted diskette.
>> + * Will not operate on an empty drive.
>> + *
>> + * @return: 0 on success, -1 if the drive is empty.
>> + */
>> +static int pick_geometry(FDrive *drv)
>> {
>> BlockBackend *blk = drv->blk;
>> const FDFormat *parse;
>> uint64_t nb_sectors, size;
>> int i, first_match, match;
>>
>> + /* We can only pick a geometry if we have a diskette. */
>> + if (!drv->media_inserted) {
>> + return -1;
>> + }
>> +
>> blk_get_geometry(blk, &nb_sectors);
>> match = -1;
>> first_match = -1;
>> @@ -290,31 +304,51 @@ static void pick_geometry(FDrive *drv)
>> }
>> drv->max_track = parse->max_track;
>> drv->last_sect = parse->last_sect;
>> - drv->drive = parse->drive;
>> - drv->disk = drv->media_inserted ? parse->drive : FLOPPY_DRIVE_TYPE_NONE;
>> + drv->disk = parse->drive;
>> drv->media_rate = parse->rate;
>> + return 0;
>> +}
>> +
>> +static void pick_drive_type(FDrive *drv)
>> +{
>> + if (pick_geometry(drv) == 0) {
>> + drv->drive = drv->disk;
>> + } else {
>> + /* Legacy behavior: default to 1.44MB floppy */
>> + drv->drive = FLOPPY_DRIVE_TYPE_144;
>> + }
>> }
>>
>> /* Revalidate a disk drive after a disk change */
>> static void fd_revalidate(FDrive *drv)
>> {
>> + int rc;
>> +
>> FLOPPY_DPRINTF("revalidate\n");
>> if (drv->blk != NULL) {
>> drv->ro = blk_is_read_only(drv->blk);
>> - pick_geometry(drv);
>> if (!drv->media_inserted) {
>> FLOPPY_DPRINTF("No disk in drive\n");
>> - } else {
>> - FLOPPY_DPRINTF("Floppy disk (%d h %d t %d s) %s\n",
>> - (drv->flags & FDISK_DBL_SIDES) ? 2 : 1,
>> - drv->max_track, drv->last_sect,
>> - drv->ro ? "ro" : "rw");
>> + drv->disk = FLOPPY_DRIVE_TYPE_NONE;
>> + } else if (!drv->media_validated) {
>> + rc = pick_geometry(drv);
>> + if (rc) {
>> + FLOPPY_DPRINTF("Could not validate floppy drive media");
>> + } else {
>> + drv->media_validated = true;
>> + FLOPPY_DPRINTF("Floppy disk (%d h %d t %d s) %s\n",
>> + (drv->flags & FDISK_DBL_SIDES) ? 2 : 1,
>> + drv->max_track, drv->last_sect,
>> + drv->ro ? "ro" : "rw");
>> + }
>> }
>> } else {
>> FLOPPY_DPRINTF("No drive connected\n");
>> drv->last_sect = 0;
>> drv->max_track = 0;
>> drv->flags &= ~FDISK_DBL_SIDES;
>> + drv->drive = FLOPPY_DRIVE_TYPE_NONE;
>> + drv->disk = FLOPPY_DRIVE_TYPE_NONE;
>> }
>> }
>>
>> @@ -2185,6 +2219,7 @@ static void fdctrl_change_cb(void *opaque, bool load)
>> drive->media_inserted = load && drive->blk &&
>> blk_is_inserted(drive->blk);
>>
>> drive->media_changed = 1;
>> + drive->media_validated = false;
>> fd_revalidate(drive);
>> }
>>
>> @@ -2221,11 +2256,12 @@ static void fdctrl_connect_drives(FDCtrl *fdctrl,
>> Error **errp)
>> }
>>
>> fd_init(drive);
>> - 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);
>> + pick_drive_type(drive);
>> }
>> + fd_revalidate(drive);
>> }
>> }
>>
>>
>
--
—js
