Am 09.08.2012 06:26, schrieb Jeff Cody:
> On 07/30/2012 05:34 PM, Supriya Kannery wrote:
>> Struct BDRVReopenState along with three reopen related functions
>> introduced for handling reopening of images safely. This can be
>> extended by each of the block drivers to reopen respective
>> image files.
>>
>> Signed-off-by: Supriya Kannery <supri...@linux.vnet.ibm.com>
>>
>> ---
>> Index: qemu/block.c
>> ===================================================================
>> --- qemu.orig/block.c
>> +++ qemu/block.c
>> @@ -859,6 +859,60 @@ unlink_and_fail:
>> return ret;
>> }
>>
>> +int bdrv_reopen_prepare(BlockDriverState *bs, BDRVReopenState **prs, int
>> flags)
>> +{
>> + BlockDriver *drv = bs->drv;
>> +
>> + return drv->bdrv_reopen_prepare(bs, prs, flags);
>> +}
>> +
>> +void bdrv_reopen_commit(BlockDriverState *bs, BDRVReopenState *rs)
>> +{
>> + BlockDriver *drv = bs->drv;
>> +
>> + drv->bdrv_reopen_commit(bs, rs);
>> +}
>> +
>> +void bdrv_reopen_abort(BlockDriverState *bs, BDRVReopenState *rs)
>> +{
>> + BlockDriver *drv = bs->drv;
>> +
>> + drv->bdrv_reopen_abort(bs, rs);
>> +}
>> +
>> +void bdrv_reopen(BlockDriverState *bs, int bdrv_flags, Error **errp)
>> +{
>> + BlockDriver *drv = bs->drv;
>> + int ret = 0;
>> + BDRVReopenState *reopen_state = NULL;
>> +
>
> We should assert if drv is NULL:
>
> assert(drv != NULL);
>
>
>> + /* Quiesce IO for the given block device */
>> + bdrv_drain_all();
>> + ret = bdrv_flush(bs);
>> + if (ret != 0) {
>> + error_set(errp, QERR_IO_ERROR);
>> + return;
>> + }
>> +
>
> We also need to reopen bs->file, so maybe something like this:
>
> /* open any file images */
> if (bs->file) {
> bdrv_reopen(bs->file, bdrv_flags, errp);
> if (errp && *errp) {
> goto exit;
> }
> }
>
> This will necessitate making the handlers in the raw.c file just stubs
> (I'll respond to that patch as well).
Doesn't this break the transactional semantics? I think you should only
prepare the bs->file reopen here and commit it when committing this one.
Kevin
