Re: [Qemu-devel] [PATCH 09/36] migration: don't "write" when migration is not active

[Anthony Liguori <anthony@codemonkey.ws>]

On 10/11/2011 05:00 AM, Juan Quintela wrote:
> If migration is not active, just ignore writes.
>
> Signed-off-by: Juan Quintela<quintela@redhat.com>
> ---
>   migration.c |    4 ++++
>   1 files changed, 4 insertions(+), 0 deletions(-)
>
> diff --git a/migration.c b/migration.c
> index 7ac1fc2..090c925 100644
> --- a/migration.c
> +++ b/migration.c
> @@ -323,6 +323,10 @@ ssize_t migrate_fd_put_buffer(void *opaque, const void *data, size_t size)
>       FdMigrationState *s = opaque;
>       ssize_t ret;
>
> +    if (s->state != MIG_STATE_ACTIVE) {
> +        return -EIO;
> +    }
> +

Buffered file is buffered.  The migration may complete before the buffer is 
completely drained.  That means additional put_buffer calls may come after the 
migration state has moved to complete.

Regards,

Anthony Liguori

>       do {
>           ret = s->write(s, data, size);
>       } while (ret == -1&&  ((s->get_error(s)) == EINTR));