image file will be created automaticly, file name is formated as:
sprintf(image_file, "%s.raw", snapshot_file);
I just add ".raw" to the file name of #1 in you comments as file name of #2.
On Wed, Mar 7, 2012 at 21:10, Stefan Hajnoczi <stefa...@gmail.com> wrote:
> On Thu, Mar 1, 2012 at 2:49 AM, Dong Xu Wang <wdon...@linux.vnet.ibm.com>
> wrote:
>> From: Dong Xu Wang <wdon...@linux.vnet.ibm.com>
>>
>> We can not use raw to support snapshot_file, but add-cow can do this.
>>
>> CC: Marcelo Tosatti <mtosa...@redhat.com>
>> CC: Kevin Wolf <kw...@redhat.com>
>> CC: Stefan Hajnoczi <stefa...@linux.vnet.ibm.com>
>> Signed-off-by: Dong Xu Wang <wdon...@linux.vnet.ibm.com>
>> ---
>> blockdev.c | 53
>> ++++++++++++++++++++++++++++++++++++++++++----
>> docs/live-block-ops.txt | 8 ++++++-
>> 2 files changed, 55 insertions(+), 6 deletions(-)
>>
>> diff --git a/blockdev.c b/blockdev.c
>> index d78aa51..c820fcb 100644
>> --- a/blockdev.c
>> +++ b/blockdev.c
>> @@ -687,12 +687,55 @@ void qmp_blockdev_snapshot_sync(const char *device,
>> const char *snapshot_file,
>> return;
>> }
>>
>> - ret = bdrv_img_create(snapshot_file, format, bs->filename,
>> - bs->drv->format_name, NULL, -1, flags);
>> - if (ret) {
>> - error_set(errp, QERR_UNDEFINED_ERROR);
>> - return;
>> + if (strcmp(format, "add-cow")) {
>> + ret = bdrv_img_create(snapshot_file, format, bs->filename,
>> + bs->drv->format_name, NULL, -1, flags);
>> + if (ret) {
>> + error_set(errp, QERR_UNDEFINED_ERROR);
>> + return;
>> + }
>
> I'm confused here because I thought we need three files:
> 1. The .add-cow file containing the bitmap
> 2. The cow image file containing allocated sectors
> 3. The backing file containing the original image
>
> We're only passing in snapshot_file and bs->filename. How will #2,
> the cow file, be created?
>
> Stefan
>
