Re: [Qemu-block] [PATCH] nbd: Advertise multi-conn for shared read-only connections

2019-08-20 Thread Nir Soffer
On Mon, Aug 19, 2019 at 9:04 PM Eric Blake wrote: > On 8/17/19 8:31 PM, Nir Soffer wrote: > >>> Also, for qemu-nbd, shouldn't we allow -e only together with -r ? > >> > >> I'm reluctant to; it might break whatever existing user is okay exposing > >> it (although such users are questionable, so

Re: [Qemu-block] [PATCH] nbd: Advertise multi-conn for shared read-only connections

2019-08-20 Thread Vladimir Sementsov-Ogievskiy
17.08.2019 17:30, Eric Blake wrote: > On 8/16/19 5:47 AM, Vladimir Sementsov-Ogievskiy wrote: > +++ b/blockdev-nbd.c @@ -189,7 +189,7 @@ void qmp_nbd_server_add(const char *device, bool has_name, const char *name,   }   exp = nbd_export_new(bs, 0, len,

Re: [Qemu-block] [PATCH] nbd: Advertise multi-conn for shared read-only connections

2019-08-19 Thread Eric Blake
On 8/17/19 8:31 PM, Nir Soffer wrote: >>> Also, for qemu-nbd, shouldn't we allow -e only together with -r ? >> >> I'm reluctant to; it might break whatever existing user is okay exposing >> it (although such users are questionable, so maybe we can argue they >> were already broken). Maybe it's

Re: [Qemu-block] [PATCH] nbd: Advertise multi-conn for shared read-only connections

2019-08-17 Thread Nir Soffer
On Sat, Aug 17, 2019 at 5:30 PM Eric Blake wrote: > On 8/16/19 5:47 AM, Vladimir Sementsov-Ogievskiy wrote: > > >>> +++ b/blockdev-nbd.c > >>> @@ -189,7 +189,7 @@ void qmp_nbd_server_add(const char *device, bool > has_name, const char *name, > >>> } > >>> > >>> exp =

Re: [Qemu-block] [PATCH] nbd: Advertise multi-conn for shared read-only connections

2019-08-17 Thread Eric Blake
On 8/16/19 5:47 AM, Vladimir Sementsov-Ogievskiy wrote: >>> +++ b/blockdev-nbd.c >>> @@ -189,7 +189,7 @@ void qmp_nbd_server_add(const char *device, bool >>> has_name, const char *name, >>>   } >>> >>>   exp = nbd_export_new(bs, 0, len, name, NULL, bitmap, >>> -

Re: [Qemu-block] [PATCH] nbd: Advertise multi-conn for shared read-only connections

2019-08-16 Thread Vladimir Sementsov-Ogievskiy
16.08.2019 13:23, Vladimir Sementsov-Ogievskiy wrote: > 15.08.2019 21:50, Eric Blake wrote: >> The NBD specification defines NBD_FLAG_CAN_MULTI_CONN, which can be >> advertised when the server promises cache consistency between >> simultaneous clients (basically, rules that determine what FUA and

Re: [Qemu-block] [PATCH] nbd: Advertise multi-conn for shared read-only connections

2019-08-16 Thread Vladimir Sementsov-Ogievskiy
15.08.2019 21:50, Eric Blake wrote: > The NBD specification defines NBD_FLAG_CAN_MULTI_CONN, which can be > advertised when the server promises cache consistency between > simultaneous clients (basically, rules that determine what FUA and > flush from one client are able to guarantee for reads

Re: [Qemu-block] [PATCH] nbd: Advertise multi-conn for shared read-only connections

2019-08-15 Thread John Snow
On 8/15/19 5:54 PM, Eric Blake wrote: > On 8/15/19 4:45 PM, John Snow wrote: >> >> >> On 8/15/19 2:50 PM, Eric Blake wrote: >>> The NBD specification defines NBD_FLAG_CAN_MULTI_CONN, which can be >>> advertised when the server promises cache consistency between >>> simultaneous clients

Re: [Qemu-block] [PATCH] nbd: Advertise multi-conn for shared read-only connections

2019-08-15 Thread Eric Blake
On 8/15/19 4:45 PM, John Snow wrote: > > > On 8/15/19 2:50 PM, Eric Blake wrote: >> The NBD specification defines NBD_FLAG_CAN_MULTI_CONN, which can be >> advertised when the server promises cache consistency between >> simultaneous clients (basically, rules that determine what FUA and >> flush

Re: [Qemu-block] [PATCH] nbd: Advertise multi-conn for shared read-only connections

2019-08-15 Thread John Snow
On 8/15/19 2:50 PM, Eric Blake wrote: > The NBD specification defines NBD_FLAG_CAN_MULTI_CONN, which can be > advertised when the server promises cache consistency between > simultaneous clients (basically, rules that determine what FUA and > flush from one client are able to guarantee for

Re: [Qemu-block] [PATCH] nbd: Advertise multi-conn for shared read-only connections

2019-08-15 Thread Richard W.M. Jones
On Thu, Aug 15, 2019 at 01:50:24PM -0500, Eric Blake wrote: > The NBD specification defines NBD_FLAG_CAN_MULTI_CONN, which can be > advertised when the server promises cache consistency between > simultaneous clients (basically, rules that determine what FUA and > flush from one client are able to