search for: nbd_rep_err_block_size_reqd

..._UNKNOWN: + set_error (ENOENT, "handshake: server has no export named '%s'", + h->export_name); + break; + case NBD_REP_ERR_SHUTDOWN: + set_error (ESHUTDOWN, "handshake: server is shutting down"); + break; + case NBD_REP_ERR_BLOCK_SIZE_REQD: + set_error (EINVAL, "handshake: server requires specific block sizes"); + break; + default: + set_error (0, "handshake: unknown reply from NBD_OPT_GO: 0x%" PRIx32, + reply); + } + } SET_NEXT_STATE (%.DEAD); return -...

...use the 32-byte extended reply header. > > + - For backwards compatibility, clients SHOULD be prepared to also > > + handle `NBD_REP_ERR_UNSUP`; in this case, only the compact > > + transmission headers will be used. > > + > > + Note that a response of `NBD_REP_ERR_BLOCK_SIZE_REQD` does not > > + make sense in response to this command, but a server MAY fail with > > + that error for a later `NBD_OPT_GO` without a client request for > > + `NBD_INFO_BLOCK_SIZE`, since the use of extended headers provides > > + more incentive for a client to...

...NBD_REP_ERR (2) +#define NBD_REP_ERR_INVALID NBD_REP_ERR (3) +#define NBD_REP_ERR_PLATFORM NBD_REP_ERR (4) +#define NBD_REP_ERR_TLS_REQD NBD_REP_ERR (5) +#define NBD_REP_ERR_UNKNOWN NBD_REP_ERR (6) +#define NBD_REP_ERR_SHUTDOWN NBD_REP_ERR (7) +#define NBD_REP_ERR_BLOCK_SIZE_REQD NBD_REP_ERR (8) +#define NBD_REP_ERR_TOO_BIG NBD_REP_ERR (9) #define NBD_INFO_EXPORT 0 /* NBD_INFO_EXPORT reply (follows fixed_new_option_reply). */ -struct fixed_new_option_reply_info_export { +struct nbd_fixed_new_option_reply_info_export { uint16_t info; /*...

...from `NBD_OPT_SET_META_CONTEXT`) issued before + this command. A client SHOULD defer all stateful option requests + until after it determines whether encryption is available. See the section on TLS above for further details. @@ -1296,6 +1393,10 @@ of the newstyle negotiation. `NBD_REP_ERR_BLOCK_SIZE_REQD` error SHOULD ensure it first sends an `NBD_INFO_BLOCK_SIZE` information reply in order to help avoid a potentially unnecessary round trip. + - `NBD_REP_ERR_EXT_HEADER_REQD`: The server requires the client to + utilize extended headers. While this may make it easier to +...

Necessary when writing a client that wants to avoid unnecessary EINVAL errors from sending unaligned requests. At some point, we may want to add synchronous convenience API wrappers that do request splitting or read-modify-write to obey server constraints while still appearing to the library client as accepting any possible request. But such a wrapper should only be synchronous and not copied to

v2 was here: https://lists.debian.org/nbd/2022/11/msg00030.html The bulk of the changes since then are: - forbid NBD_OPT_EXPORT_NAME once extended headers are negotiated (Wouter) - consistently use 'maximum payload', rather than a haphazard mix of 'maximum block payload' (Vladimir) At this point, I want to make sure we are happy with the spec before re-posting patches for

We should have only one NBD protocol file. Let's make nbdkit's version the canonical one, and use it in libnbd. Rich.