search for: get_meta_context

...This call adds one metadata context to the list to be negotiated. You can call it as many times as needed. The list is initially -empty when the handle is created. +empty when the handle is created; you can check the contents of +the list with L<nbd_get_nr_meta_contexts(3)> and +L<nbd_get_meta_context(3)>, or clear it with +L<nbd_clear_meta_contexts(3)>. The NBD protocol limits meta context names to 4096 bytes, but servers may not support the full length. The encoding of meta @@ -991,9 +994,73 @@ C<LIBNBD_CONTEXT_> for some well-known contexts, but you are free to pass in oth...

On Mon, Sep 28, 2020 at 05:05:16PM -0500, Eric Blake wrote: > + "get_meta_context", { > + default_call with > + args = [ Int "i" ]; ret = RString; Previously we have only used the Int parameter type for things which are plausibly integers (timeouts, signal numbers). This one really ought to be an unsigned or better still a size_t. Would it help if I...

I'm posting this now, as I'm at the end of a workday and I got things working for manual experimentation. Still to do: - write interop tests for qemu-nbd and nbdkit (including my proposed patch addition of qemu-nbd -A to show qemu:allocation-depth) - figure out if we can make 'nbdinfo --map' use the new API to automatically select all contexts advertised by the server Eric Blake

...dle.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/generator/API.ml b/generator/API.ml index 770f41e..fd6f033 100644 --- a/generator/API.ml +++ b/generator/API.ml @@ -1024,7 +1024,7 @@ what it actually supports, see L<nbd_can_meta_context(3)>."; "get_meta_context", { default_call with - args = [ Int "i" ]; ret = RString; + args = [ SizeT "i" ]; ret = RString; shortdesc = "return the i'th meta context request"; longdesc = "\ During connection libnbd can negotiate zero or more metadata diff --g...

On 9/29/20 6:26 AM, Richard W.M. Jones wrote: > On Mon, Sep 28, 2020 at 05:05:16PM -0500, Eric Blake wrote: >> + "get_meta_context", { >> + default_call with >> + args = [ Int "i" ]; ret = RString; > > Previously we have only used the Int parameter type for things which > are plausibly integers (timeouts, signal numbers). This one really > ought to be an unsigned or better still a...

In v2: ack'ed preliminary patches have been pushed, and I've added a lot of testsuite coverage as well as putting the new API to use in nbdinfo. Eric Blake (2): api: Add nbd_opt_list_meta_context info: List available meta-contexts lib/internal.h | 1 + generator/API.ml | 84 ++++++++-

...ot;; Link "opt_list_meta_context"]; + }; + "aio_pread", { default_call with args = [ BytesPersistOut ("buf", "count"); UInt64 "offset" ]; @@ -2884,6 +2962,8 @@ let first_version = [ "get_nr_meta_contexts", (1, 6); "get_meta_context", (1, 6); "clear_meta_contexts", (1, 6); + "opt_list_meta_context", (1, 6); + "aio_opt_list_meta_context", (1, 6); (* These calls are proposed for a future version of libnbd, but * have not been added to any released version so far. diff --git a/gener...