From 69404169fd3c7021d593ce67502f202082d84f49 Mon Sep 17 00:00:00 2001 From: Markus Armbruster Date: Tue, 4 Oct 2011 16:24:26 +0200 Subject: [PATCH 51/76] fdc: Make media change detection more robust RH-Author: Markus Armbruster Message-id: <1317745491-18401-44-git-send-email-armbru@redhat.com> Patchwork-id: 33631 O-Subject: [PATCH RHEL-6.2 qemu-kvm 43/68] fdc: Make media change detection more robust Bugzilla: 742458 RH-Acked-by: Paolo Bonzini RH-Acked-by: Amit Shah RH-Acked-by: Juan Quintela fdctrl_change_cb() gets called on a virtual media change via monitor. It would be nice if host device block drivers called it on physical media change, but they don't. bdrv_media_changed() lets you poll for media change, but it returns "don't know" except with block driver "host_floppy". FDrive member media_changed gets set on device initialization and by fdctrl_change_cb(), and cleared by fdctrl_media_changed(). Thus, it's set on first entry to fdctrl_media_changed() since device initialization or virtual media change. fdctrl_media_changed() ignores media_changed unless bdrv_media_changed() returns "don't know". If we change media via monitor (setting media_changed), and the new media's block driver returns 0, we lose. Fortunately, "host_floppy" always returns 1 on first call. Brittle. Clean it up not to rely on it. Signed-off-by: Markus Armbruster Signed-off-by: Kevin Wolf (cherry picked from commit 18d90055293adc4937c91fb7b87743b1994d8bc5) --- hw/fdc.c | 12 ++++++++---- 1 files changed, 8 insertions(+), 4 deletions(-) Signed-off-by: Michal Novotny --- hw/fdc.c | 12 ++++++++---- 1 files changed, 8 insertions(+), 4 deletions(-) diff --git a/hw/fdc.c b/hw/fdc.c index 2378e3f..a96244e 100644 --- a/hw/fdc.c +++ b/hw/fdc.c @@ -1000,11 +1000,15 @@ static int fdctrl_media_changed(fdrive_t *drv) if (!drv->bs) return 0; - ret = bdrv_media_changed(drv->bs); - if (ret < 0) { - ret = drv->media_changed; + if (drv->media_changed) { + drv->media_changed = 0; + ret = 1; + } else { + ret = bdrv_media_changed(drv->bs); + if (ret < 0) { + ret = 0; /* we don't know, assume no */ + } } - drv->media_changed = 0; if (ret) { fd_revalidate(drv); } -- 1.7.4.4