search for: opt_info

...dinfo, I'm going ahead and pushing this now. We may still want to add further nbd_opt_* commands for other fine-grained tuning of negotiation, but for now, I think things have stabilized on this end, and I can return to polishing .list_exports on the nbdkit end. Eric Blake (2): api: add nbd_opt_info, nbd_aio_opt_info info: Use nbd_opt_info for fewer handles during --list docs/libnbd.pod | 4 + info/nbdinfo.pod | 2 + generator/API.ml | 116 ++++++--- generator/states-newstyle-opt-go.c |...

The NBD spec says that additional information in response to NBD_OPT_GO or NBD_OPT_INFO, such as NBD_INFO_NAME, is optional, but also recommends that if a client hints about wanting a particular piece of information, that it is better for the server to reply to those known hints. This is also the the only way for a client to learn the canonical name that is used when connecting to th...

...#39;nbd_set_full_info()' as the knob for whether a client will request name and description during NBD_OPT_GO; adding this functionality in nbdkit makes it easier to test that API in libnbd. Also note that 'nbdinfo --list' released with libnbd 1.4 does NOT query descriptions during NBD_OPT_INFO (it assumes that the description during NBD_OPT_LIST is sufficient); but later libnbd does as a fallback for when the list description is empty, making it trickier to write a test that passes across libnbd versions. --- docs/nbdkit-filter.pod | 9 ++++ docs/nbdkit-plugin.pod...

Right now, we require the user to supply potential metacontext names in advance, without knowing what the server actually supports until after the connection or nbd_opt_info call is complete. But the NBD protocol also supports a client being able to query what contexts a server supports, including where a client asks with a prefix and the server replies back with all answers that match the prefix. Not to mention this will allow nbdinfo to gain full feature parity wit...

Most known NBD clients do not bother with NBD_OPT_INFO (except for clients like 'qemu-nbd --list' that don't ever intend to connect), but go straight to NBD_OPT_GO. However, it's not too hard to hack up qemu to add in an extra client step (whether info on the same name, or more interestingly, info on a different name), as a patch again...

The first one is the nastiest - it is an assertion failure caused by a spec-compliant client and introduced by our security fix that was released in 1.14.1. Eric Blake (4): server: Fix regression for NBD_OPT_INFO before NBD_OPT_GO server: Fix back-to-back SET_META_CONTEXT server: Forbid NUL in export and context names server: Fix OPT_GO on different export than SET_META_CONTEXT server/internal.h | 5 ++- server/backend.c | 13 ++++++ server/connections.c...

Well, I'm not quite done (I still want to get nbdinfo to work on a single nbd connection for all cases when reading the heads of the file is not required), but I'm happy with patches 1-11, and 12-13 show where I'm headed for getting NBD_OPT_INFO to work. Posting now to see if some of the earlier patches are ready to commit while I continue working on the latter half. Eric Blake (13): api: Add nbd_set_full_info and friends info: Improve info without --list api: Add nbd_is_state_negotiating for new state api: Permit several existin...

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

Squash this into opt_go? into opt_info? Standalone? Testing: why does python not throw an exception: $ ./run nbdsh Welcome to nbdsh, the shell for interacting with Network Block Device (NBD) servers. The ‘nbd’ module has already been imported and there is an open NBD handle called ‘h’. h.connect_tcp ("remote", "10809&...

This is a revision of my .default_export work, plus new work on .export_descriptions and a new exportname filter. I think it is now ready to check in. Things I'd still like in 1.22: - the file plugin should implement .list_exports (patch already posted, but it needs rebasing on this series) - the ext2 filter should override .list_exports when in exportname mode - the nbd plugin should be

...a/generator/API.ml b/generator/API.ml index 36033817..d1849710 100644 --- a/generator/API.ml +++ b/generator/API.ml @@ -953,23 +953,24 @@ "set_request_meta_context", { (all C<nbd_connect_*> calls when L<nbd_set_opt_mode(3)> is false, or L<nbd_opt_go(3)> and L<nbd_opt_info(3)> when option mode is enabled) will also try to issue NBD_OPT_SET_META_CONTEXT when -the server supports structured replies and any contexts were -registered by L<nbd_add_meta_context(3)>. The default setting -is true; however the extra step of negotiating meta contexts is -not always...

It's been several weeks since I posted v2 (I got distracted by improving libnbd to better test things, which in turn surfaced some major memory leak problems in nbdsh that are now fixed). Many of the patches are minor rebases from v2, with the biggest changes being fallout from: - patch 2: rename nbdkit_add_default_export to nbdkit_use_default_export - overall: this missed 1.22, so update

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 ++++++++-

More patches on the way for improving .list_exports signature and adding .export_description, but this is the promised code showing why nbdkit_string_intern is useful. Patch 4 is somewhat RFC: we could either add new API to take the boilerplate from: foo_config(const char *key, const char *value) { if (strcmp (key, "file") == 0) { CLEANUP_FREE char *tmp = nbdkit_realpath (value);

This adds coalescing of adjacent extents of the same type, as mentioned by Eric Blake in the commit message here: https://github.com/libguestfs/libnbd/commit/46072f6611f80245846a445766da071e457b00cd The patch series is rather long because it detours through adding the <vector.h> library from nbdkit into libnbd and replacing ad hoc uses of realloc, char ** etc in various places. Rich.