Re: [Qemu-devel] Re: [PATCH v2] virtio-blk physical block size

2010-01-05 Thread Jamie Lokier
Avi Kivity wrote: > Physical block size is the what the logical block size would have been > is software didn't suck. In theory they should be the same, but since > compatibility reaons clamp the logical block size to 512, they have to > differ. A disk may have a physical block size of 4096 an

Re: [Qemu-devel] Re: [PATCH v2] virtio-blk physical block size

2010-01-05 Thread Jamie Lokier
Avi Kivity wrote: > On 01/05/2010 02:56 PM, Rusty Russell wrote: > > > >>Those should be the same for any sane interface. They are for classical > >>disk devices with larger block sizes (MO, s390 dasd) and also for the > >>now appearing 4k sector scsi disks. But in the ide world people are > >>co

Re: [Qemu-devel] Re: [PATCH v2] virtio-blk physical block size

2010-01-05 Thread Rusty Russell
On Mon, 4 Jan 2010 07:00:35 pm Christoph Hellwig wrote: > On Mon, Jan 04, 2010 at 01:38:51PM +1030, Rusty Russell wrote: > > I thought this was what I was doing, but I have shown over and over that > > I have no idea about block devices. > > > > Our current driver treats BLK_SIZE as the logical an

Re: [Qemu-devel] Re: [PATCH v2] virtio-blk physical block size

2010-01-05 Thread Avi Kivity
On 01/05/2010 02:56 PM, Rusty Russell wrote: > >> Those should be the same for any sane interface. They are for classical >> disk devices with larger block sizes (MO, s390 dasd) and also for the >> now appearing 4k sector scsi disks. But in the ide world people are >> concerned about dos/window l