From a547697ef31e2879f38f5ac6f71f67751560283e Mon Sep 17 00:00:00 2001 From: Xiao Wang Date: Wed, 6 Apr 2011 11:07:21 -0300 Subject: [RHEL6 qemu-kvm PATCH 2/5] floppy: save and restore DIR register RH-Author: Xiao Wang Message-id: <20110406110721.11772.11724.stgit@dhcp-91-7.nay.redhat.com.englab.nay.redhat.com> Patchwork-id: 21520 O-Subject: [PATCH] floppy: save and restore DIR register Bugzilla: 681777 RH-Acked-by: Kevin Wolf RH-Acked-by: Juan Quintela RH-Acked-by: Paolo Bonzini Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=681777 Upstream: POST V4 to the list Brew Build: https://brewweb.devel.redhat.com/taskinfo?taskID=3235081 Test status: Tested in my local desktop Notes: Since drives_reopen() in RHEL6 also call bdrv_close()/bdrv_open() which may also touch media_changed flag after migration. I simply cache it there to make sure its value was not changed after drives_reopen(). We need to keep DIR register unchanged across migration, but currently it depends on the media_changed flags from block layer. Since we do not save/restore it and the bdrv_open() called in dest node may set the media_changed flag when trying to open floppy image, guest driver may think the floppy have changed after migration. To fix this, a new filed media_changed in FDrive strcutre was introduced in order to save and restore the it from block layer through pre_save/post_load callbacks. Signed-off-by: Jason Wang --- hw/fdc.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++ vl.c | 2 ++ 2 files changed, 51 insertions(+), 0 deletions(-) Signed-off-by: Eduardo Habkost --- hw/fdc.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++ vl.c | 2 ++ 2 files changed, 51 insertions(+), 0 deletions(-) diff --git a/hw/fdc.c b/hw/fdc.c index 35c1a9e..e78d76b 100644 --- a/hw/fdc.c +++ b/hw/fdc.c @@ -35,6 +35,7 @@ #include "sysbus.h" #include "qdev-addr.h" #include "sysemu.h" +#include "block_int.h" /********************************************************/ /* debug Floppy devices */ @@ -96,6 +97,7 @@ typedef struct fdrive_t { uint8_t max_track; /* Nb of tracks */ uint16_t bps; /* Bytes per sector */ uint8_t ro; /* Is read-only */ + uint8_t media_changed; /* Is media changed */ } fdrive_t; static void fd_init (fdrive_t *drv) @@ -632,6 +634,45 @@ static CPUWriteMemoryFunc * const fdctrl_mem_write_strict[3] = { NULL, }; +static void fdrive_media_changed_pre_save(void *opaque) +{ + fdrive_t *drive = opaque; + + drive->media_changed = drive->bs->media_changed; +} + +static int fdrive_media_changed_post_load(void *opaque, int version_id) +{ + fdrive_t *drive = opaque; + + if (drive->bs != NULL) { + drive->bs->media_changed = drive->media_changed; + } + + /* User ejected the floppy when drive->bs == NULL */ + return 0; +} + +static bool fdrive_media_changed_needed(void *opaque) +{ + fdrive_t *drive = opaque; + + return (drive->bs != NULL && drive->bs->media_changed != 1); +} + +static const VMStateDescription vmstate_fdrive_media_changed = { + .name = "fdrive/media_changed", + .version_id = 1, + .minimum_version_id = 1, + .minimum_version_id_old = 1, + .pre_save = fdrive_media_changed_pre_save, + .post_load = fdrive_media_changed_post_load, + .fields = (VMStateField[]) { + VMSTATE_UINT8(media_changed, fdrive_t), + VMSTATE_END_OF_LIST() + } +}; + static const VMStateDescription vmstate_fdrive = { .name = "fdrive", .version_id = 1, @@ -642,6 +683,14 @@ static const VMStateDescription vmstate_fdrive = { VMSTATE_UINT8(track, fdrive_t), VMSTATE_UINT8(sect, fdrive_t), VMSTATE_END_OF_LIST() + }, + .subsections = (VMStateSubsection[]) { + { + .vmsd = &vmstate_fdrive_media_changed, + .needed = &fdrive_media_changed_needed, + } , { + /* empty */ + } } }; diff --git a/vl.c b/vl.c index 9c2ec66..4e800b2 100644 --- a/vl.c +++ b/vl.c @@ -2257,8 +2257,10 @@ int drives_reopen(void) QTAILQ_FOREACH(dinfo, &drives, next) { if (dinfo->opened && !bdrv_is_read_only(dinfo->bdrv)) { int res; + int media_changed = dinfo->bdrv->media_changed; bdrv_close(dinfo->bdrv); res = drive_open(dinfo); + dinfo->bdrv->media_changed = media_changed; if (res) { fprintf(stderr, "qemu: re-open of %s failed wth error %d\n", dinfo->file, res); -- 1.7.3.2