| Message ID | 1302086071-15742-1-git-send-email-jasowang@redhat.com |
|---|---|
| State | New |
| Headers | show |
Jason Wang <jasowang@redhat.com> wrote: > 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 <jasowang@redhat.com> > --- > > Changed from V3: > According to Juan's suggestions, back to v2 and just add the checking for > media_changed "changed" in .needed. > Do not fail the migration when src have a drive but dest does not, we can treat > it as user ejected the floppy. > > Changed from V2: > According to Paolo's suggestions, a default_migration_media_changed property was > added to avoid saving subsections as much as possible. Its was set media_changed > in pre_load callback and then we can avoid the saving when it was equal to the > media_changed when migrating the FDrive. Behaviors of elder machine types are > also kept through compat_props. > > Changed from V1: > Check the drive->bs during post_load. > > hw/fdc.c | 51 ++++++++++++++++++++++++++++++++++++++++++++++++++- > 1 files changed, 50 insertions(+), 1 deletions(-) > Reviewed-by: Juan Quintela <quintela@redhat.com> This solution is way less invasive that v3, and achieves exactly the same compatibility.
On 04/06/2011 02:13 PM, Juan Quintela wrote: > Jason Wang<jasowang@redhat.com> wrote: >> 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<jasowang@redhat.com> >> --- >> >> Changed from V3: >> According to Juan's suggestions, back to v2 and just add the checking for >> media_changed "changed" in .needed. >> Do not fail the migration when src have a drive but dest does not, we can treat >> it as user ejected the floppy. >> >> Changed from V2: >> According to Paolo's suggestions, a default_migration_media_changed property was >> added to avoid saving subsections as much as possible. Its was set media_changed >> in pre_load callback and then we can avoid the saving when it was equal to the >> media_changed when migrating the FDrive. Behaviors of elder machine types are >> also kept through compat_props. >> >> Changed from V1: >> Check the drive->bs during post_load. >> >> hw/fdc.c | 51 ++++++++++++++++++++++++++++++++++++++++++++++++++- >> 1 files changed, 50 insertions(+), 1 deletions(-) >> > > Reviewed-by: Juan Quintela<quintela@redhat.com> > > This solution is way less invasive that v3, and achieves exactly the > same compatibility. True, thanks for putting up with the reviews! :) Acked-by: Paolo Bonzini <pbonzini@redhat.com> Paolo
Am 06.04.2011 12:34, schrieb Jason Wang: > 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 <jasowang@redhat.com> Thanks, applied to the block branch. Kevin
diff --git a/hw/fdc.c b/hw/fdc.c index 9fdbc75..edf0360 100644 --- a/hw/fdc.c +++ b/hw/fdc.c @@ -36,6 +36,7 @@ #include "qdev-addr.h" #include "blockdev.h" #include "sysemu.h" +#include "block_int.h" /********************************************************/ /* debug Floppy devices */ @@ -82,6 +83,7 @@ typedef struct FDrive { 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; static void fd_init(FDrive *drv) @@ -533,16 +535,63 @@ static CPUWriteMemoryFunc * const fdctrl_mem_write_strict[3] = { NULL, }; +static void fdrive_media_changed_pre_save(void *opaque) +{ + FDrive *drive = opaque; + + drive->media_changed = drive->bs->media_changed; +} + +static int fdrive_media_changed_post_load(void *opaque, int version_id) +{ + FDrive *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 *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), + VMSTATE_END_OF_LIST() + } +}; + static const VMStateDescription vmstate_fdrive = { .name = "fdrive", .version_id = 1, .minimum_version_id = 1, .minimum_version_id_old = 1, - .fields = (VMStateField []) { + .fields = (VMStateField[]) { VMSTATE_UINT8(head, FDrive), VMSTATE_UINT8(track, FDrive), VMSTATE_UINT8(sect, FDrive), VMSTATE_END_OF_LIST() + }, + .subsections = (VMStateSubsection[]) { + { + .vmsd = &vmstate_fdrive_media_changed, + .needed = &fdrive_media_changed_needed, + } , { + /* empty */ + } } };
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 <jasowang@redhat.com> --- Changed from V3: According to Juan's suggestions, back to v2 and just add the checking for media_changed "changed" in .needed. Do not fail the migration when src have a drive but dest does not, we can treat it as user ejected the floppy. Changed from V2: According to Paolo's suggestions, a default_migration_media_changed property was added to avoid saving subsections as much as possible. Its was set media_changed in pre_load callback and then we can avoid the saving when it was equal to the media_changed when migrating the FDrive. Behaviors of elder machine types are also kept through compat_props. Changed from V1: Check the drive->bs during post_load. hw/fdc.c | 51 ++++++++++++++++++++++++++++++++++++++++++++++++++- 1 files changed, 50 insertions(+), 1 deletions(-)