On 02/23/2017 07:13 AM, Paolo Bonzini wrote:
>
>
> On 22/02/2017 21:34, Eric Blake wrote:
>>
>>> Oh, so it's the smallest "good" transfer size, or the preferred
>>> alignment. That's not the same as the SCSI definition, which is:
>>>
>>>If a device server receives one of these commands with
On 22/02/2017 21:34, Eric Blake wrote:
>
>> Oh, so it's the smallest "good" transfer size, or the preferred
>> alignment. That's not the same as the SCSI definition, which is:
>>
>>If a device server receives one of these commands with a transfer
>>size greater than this value, then the
On 02/22/2017 11:26 AM, Paolo Bonzini wrote:
>
>
> On 22/02/2017 18:11, Eric Blake wrote:
+/* preferred - At least 4096, but larger as appropriate. */
+sizes[1] = MAX(blk_get_opt_transfer(exp->blk), 4096);
>>
>> The NBD specification requires a non-zero power-of-2 number if the
On 22/02/2017 18:11, Eric Blake wrote:
>>> +/* preferred - At least 4096, but larger as appropriate. */
>>> +sizes[1] = MAX(blk_get_opt_transfer(exp->blk), 4096);
>
> The NBD specification requires a non-zero power-of-2 number if the
> server transmits the block size at all; 1 is the idea
On 02/22/2017 10:51 AM, Paolo Bonzini wrote:
>
>
> On 21/02/2017 03:42, Eric Blake wrote:
>> +/* Send NBD_INFO_BLOCK_SIZE always, but tweak the minimum size
>> + * according to whether the client requested it, and according to
>> + * whether this is OPT_INFO or OPT_GO. */
>> +/* m
On 21/02/2017 03:42, Eric Blake wrote:
> +/* Send NBD_INFO_BLOCK_SIZE always, but tweak the minimum size
> + * according to whether the client requested it, and according to
> + * whether this is OPT_INFO or OPT_GO. */
> +/* minimum - 1 for back-compat, or 512 if client is new eno
The upstream NBD Protocol has defined a new extension to allow
the server to advertise block sizes to the client, as well as
a way for the client to inform the server that it intends to
obey block sizes.
Thanks to a recent fix (commit df7b97ff), our real minimum
transfer size is always 1 (the bloc
