similar to: [PATCH libnbd] info: Write output atomically.

Now that we have an API, it's time to put it to use. --- info/nbdinfo.pod | 6 ++++++ info/nbdinfo.c | 18 ++++++++++++++++++ 2 files changed, 24 insertions(+) diff --git a/info/nbdinfo.pod b/info/nbdinfo.pod index 9761551..d0d20a9 100644 --- a/info/nbdinfo.pod +++ b/info/nbdinfo.pod @@ -45,6 +45,9 @@ L<https://github.com/NetworkBlockDevice/nbd/blob/master/doc/uri.md>):

Use the just-added nbd_opt_list_meta_context() API to give more details about each export (matching what 'qemu-nbd --list' already does). Note that this requires some shuffling: listing meta exports requires being in opt mode, but is easiest to do in list_one_export(), which requires setting opt_mode in more code paths, and deferring ready mode until the last possible minute during

On 10/7/23 11:27, Richard W.M. Jones wrote: > On Fri, Oct 06, 2023 at 10:18:09AM -0500, Eric Blake wrote: >> Adding a human-readable size for block constraints is useful. For: >> >> $ ./run nbdinfo -- [ nbdkit memory \ >> --filter=blocksize-policy blocksize-preferred=32k 1M ] | grep pref >> >> this changes pre-patch: >> block_size_preferred: 32768

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

Exposing a description in single mode is harder: we'd have to request NBD_INFO_DESCRIPTION during NBD_OPT_GO. For now, the API only supports descriptions in list mode. --- info/info-list-json.sh | 3 ++- info/info-list.sh | 3 ++- info/nbdinfo.c | 21 ++++++++++++++++----- 3 files changed, 20 insertions(+), 7 deletions(-) diff --git a/info/info-list-json.sh

--- info/Makefile.am | 4 + info/info-map-base-allocation-json.sh | 52 ++++++++++ info/info-map-base-allocation.sh | 49 ++++++++++ info/nbdinfo.c | 134 ++++++++++++++++++++++++-- info/nbdinfo.pod | 39 +++++++- 5 files changed, 271 insertions(+), 7 deletions(-) diff --git a/info/Makefile.am b/info/Makefile.am index

This rounds up the remaining bugs that I originally identified in: https://www.redhat.com/archives/libguestfs/2020-July/msg00153.html Eric Blake (4): api: Permit export list APIs when Connected info: Support --list with serializing servers info: Fix --json output when list size != 1 info: Permit --size --json generator/API.ml | 6 +++--- info/info-list-json.sh | 9 +++++++++

This is a rough-and-ready implementation of nbdinfo --map option, to display the allocation and other metadata of NBD exports. I only tested it lightly against nbdkit. It needs at least some tests. Command like these should work: nbdinfo --map nbd://localhost nbdinfo --map=qemu:dirty-bitmap nbd://localhost Rich.

Otherwise, we get a failure due to Numerical result out of range. And for safety's sake, we are best capping our request to an aligned value, if the server insists on minimum alignment. Fixes: f3fd935c --- info/nbdinfo.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/info/nbdinfo.c b/info/nbdinfo.c index 1afdf98..2b22f51 100644 --- a/info/nbdinfo.c +++

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.

Based on Laszlo's approval of my idea here: https://listman.redhat.com/archives/libguestfs/2023-September/032661.html but as I would like to resync human-size.h back to nbdkit, I'm reluctant to apply patch 1 this until I get Rich's consent to relicensing (this email serves as my consent for my contribution here): https://listman.redhat.com/archives/libguestfs/2023-October/032755.html

A rather trivial decoding; we may enhance it further if qemu extends things to give an integer depth alongside its tri-state encoding. --- I'll wait to push this to libnbd until the counterpart qemu patches land upstream, although it looks like I've got positive review. info/nbdinfo.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/info/nbdinfo.c b/info/nbdinfo.c index

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 ++++++++-

An incremental improvement on top of listing exports. I still think it's worth experimenting with revisiting how our API for list mode should actually work [1] (so that we can reuse a single connection for both grabbing the list and finally using NBD_OPT_GO), but this change was easier to whip together while still thinking about that. [1]

Fixes bugs with JSON output in the previous patch, and adds some tests. Rich.

This continues the changes for adding NBD_OPT_LIST support. Now, instead of libnbd malloc'ing storage itself, the user passes a callback that can handle name/description pairs however it likes, and we get rid of the artificial cap at 10000 exports. However, the user will probably end up malloc'ing a list themselves, as we can't call nbd_set_export_name, or even request NBD_OPT_INFO

A single integer IS a valid JSON document, after all, at least according to RFC8259. --- info/nbdinfo.c | 5 ----- 1 file changed, 5 deletions(-) diff --git a/info/nbdinfo.c b/info/nbdinfo.c index f37ffea..2e0bf27 100644 --- a/info/nbdinfo.c +++ b/info/nbdinfo.c @@ -158,11 +158,6 @@ main (int argc, char *argv[]) usage (stderr, EXIT_FAILURE); /* You can combine certain options. */ - if

On 10/16/20 10:23 AM, Eric Blake wrote: > A rather trivial decoding; we may enhance it further if qemu extends > things to give an integer depth alongside its tri-state encoding. > --- > > I'll wait to push this to libnbd until the counterpart qemu patches > land upstream, although it looks like I've got positive review. Whoops, I accidentally pushed this before qemu

This replaces 13/13 of my v2 series; and now that it has pretty good testsuite coverage and demonstrable performance improvement to nbdinfo, 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

On 10/6/20 11:54 AM, Richard W.M. Jones wrote: > If the server fails, nbdinfo can write partial output before the error > message (albeit on different channels). Here is an example: > > $ nbdkit eval open='echo EIO fail >&2; exit 1' --run 'nbdinfo --json "$uri"' > { > "protocol": "newstyle-fixed", >