From mboxrd@z Thu Jan 1 00:00:00 1970 From: Asias He Subject: Re: [PATCH] vhost-blk: Add vhost-blk support v2 Date: Wed, 24 Oct 2012 11:08:38 +0800 Message-ID: <50875BB6.90809@redhat.com> References: <1349769918-8611-1-git-send-email-asias@redhat.com> <20121011124125.GA8074@redhat.com> <507818BE.7060404@redhat.com> <87d30go1g7.fsf@rustcorp.com.au> <20121018063040.GA15676@redhat.com> <87mwzehwzi.fsf@rustcorp.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <87mwzehwzi.fsf@rustcorp.com.au> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: Rusty Russell Cc: Paolo Bonzini , virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, "Michael S. Tsirkin" List-Id: virtualization@lists.linuxfoundation.org On 10/23/2012 08:07 AM, Rusty Russell wrote: > "Michael S. Tsirkin" writes: >> On Thu, Oct 18, 2012 at 02:50:56PM +1030, Rusty Russell wrote: >>> Asias He writes: >>>>>> +#define BLK_HDR 0 >>>>> >>>>> What's this for, exactly? Please add a comment. >>>> >>>> The block headr is in the first and separate buffer. >>> >>> Please don't assume this! We're trying to fix all the assumptions in >>> qemu at the moment. >>> >>> vhost_net handles this correctly, taking bytes off the descriptor chain >>> as required. >>> >>> Thanks, >>> Rusty. >> >> BTW are we agreed on the spec update that makes cmd 32 bytes? > > vhost-blk doesn't handle scsi requests, does it? No, it doesn't handle scsi requests currently. > > But since we're forced to use a feature bit, we could just put the cmd > size in explicitly. Though Paulo seems convinced that 32 is always > sufficient. Whoever implements it gets to decide... > > Here's my TODO list: > 1) Create qemu helpers to efficiently handle iovecs. > 2) Switch all the qemu devices to use them. > 3) ... except a special hack for virtio-blk in old-layout mode. > 4) Implement pci capability layout RFC for qemu. > - Detect whether guest uses capabilities. > - Device config in new mode is le. > - Add strict checking mode for extra compliance checks? > 5) Add explicit size-based accessors to virtio_config in kernel. > 6) Update pci capability RFC patches for linux to match. > - Use explicit accessors to allow for endian conversion. > 6) Push virtio torture patch to test variable boundaries. > 7) Update spec. > > That should keep me amused for a while... > > Cheers, > Rusty. > -- Asias