From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58602) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XKk0A-0004Ir-Jg for qemu-devel@nongnu.org; Fri, 22 Aug 2014 04:15:23 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XKk01-0007Sj-J0 for qemu-devel@nongnu.org; Fri, 22 Aug 2014 04:15:14 -0400 Received: from mail-we0-x22e.google.com ([2a00:1450:400c:c03::22e]:48317) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XKk01-0007R9-D4 for qemu-devel@nongnu.org; Fri, 22 Aug 2014 04:15:05 -0400 Received: by mail-we0-f174.google.com with SMTP id x48so10274281wes.5 for ; Fri, 22 Aug 2014 01:15:04 -0700 (PDT) Sender: Paolo Bonzini Message-ID: <53F6FBFF.1010504@redhat.com> Date: Fri, 22 Aug 2014 10:14:55 +0200 From: Paolo Bonzini MIME-Version: 1.0 References: <1408622216-9578-1-git-send-email-famz@redhat.com> <1408622216-9578-2-git-send-email-famz@redhat.com> <53F5E289.8050703@redhat.com> <20140822012336.GB3410@T430.redhat.com> In-Reply-To: <20140822012336.GB3410@T430.redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [RFC PATCH 1/9] block: Add bdrv_aio_cancel_async List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Fam Zheng Cc: Kevin Wolf , qemu-devel@nongnu.org, Stefan Hajnoczi Il 22/08/2014 03:23, Fam Zheng ha scritto: > What about we save cb and opaque locally, and set acb->cb to a nop. When cancel > is done we can call the original cb? That might work but needs some auditing. Right now the AIOCB is still valid when the callback is called, and this would be changed. Also, having different semantics for cancellation vs. completion would be painful. Paolo