Status flags definition for NBD_REPLY_TYPE_BLOCK_STATUS

[Connor Kuehl <cipkuehl@gmail.com>]

Hello,

I am implementing the client-side of the NBD protocol and I've gotten
a little stuck on the NBD_REPLY_TYPE_BLOCK_STATUS structured reply.

The protocol description[1] states:

> * `NBD_REPLY_TYPE_BLOCK_STATUS` (5)
> 
>   *length* MUST be 4 + (a positive integer multiple of 8).  This reply
>   represents a series of consecutive block descriptors where the sum
>   of the length fields within the descriptors is subject to further
>   constraints documented below.  A successful block status request MUST
>   have exactly one status chunk per negotiated metadata context ID.
> 
>   The payload starts with:
> 
>   32 bits, metadata context ID  
> 
>   and is followed by a list of one or more descriptors, each with this
>   layout:
> 
>   32 bits, length of the extent to which the status below
>      applies (unsigned, MUST be nonzero)  
>   32 bits, status flags  

I can't seem to find the definition for these status flags. It's likely
I may have just missed it. Any pointers will be much appreciated.

Thank you,

Connor

[1] https://github.com/NetworkBlockDevice/nbd/blob/master/doc/proto.md