search for: callback_is_nul

...+++++++++++ > lib/internal.h | 18 +++++++++--------- > 2 files changed, 24 insertions(+), 9 deletions(-) > > +++ b/lib/internal.h > @@ -274,20 +274,20 @@ struct command { > }; > > /* Test if a callback is "null" or not, and set it to null. */ > -#define CALLBACK_IS_NULL(cb) ((cb).callback == NULL) > +#define CALLBACK_IS_NULL(cb) ((cb).callback == NULL && (cb).free == NULL) Semantic change. In generator, you used CALLBACK_IS_NULL() for both Closure and OClosure. For OClosure, the new semantics are still correct. But for Closure, we now no lon...

...erator +++ b/generator/generator @@ -3576,7 +3576,7 @@ let generate_lib_api_c () = let value = match errcode with | Some value -> value | None -> assert false in - pr " if (%s_callback.callback == NULL) {\n" cbname; + pr " if (CALLBACK_IS_NULL (%s_callback)) {\n" cbname; pr " set_error (EFAULT, \"%%s cannot be NULL\", \"%s\");\n" cbname; pr " ret = %s;\n" value; pr " goto out;\n"; @@ -3689,7 +3689,7 @@ let generate_lib_api_c () = List.iter...

...+++--------- > > 2 files changed, 24 insertions(+), 9 deletions(-) > > > > > +++ b/lib/internal.h > > @@ -274,20 +274,20 @@ struct command { > > }; > > > > /* Test if a callback is "null" or not, and set it to null. */ > > -#define CALLBACK_IS_NULL(cb) ((cb).callback == NULL) > > +#define CALLBACK_IS_NULL(cb) ((cb).callback == NULL && (cb).free == NULL) > > Semantic change. In generator, you used CALLBACK_IS_NULL() for both > Closure and OClosure. For OClosure, the new semantics are still > correct. But f...

...e invoked at a point where the libnbd lock is held; as diff --git a/lib/internal.h b/lib/internal.h index 1344d98..ee59582 100644 --- a/lib/internal.h +++ b/lib/internal.h @@ -274,20 +274,20 @@ struct command { }; /* Test if a callback is "null" or not, and set it to null. */ -#define CALLBACK_IS_NULL(cb) ((cb).callback == NULL) +#define CALLBACK_IS_NULL(cb) ((cb).callback == NULL && (cb).free == NULL) #define CALLBACK_IS_NOT_NULL(cb) (! CALLBACK_IS_NULL ((cb))) -#define SET_CALLBACK_TO_NULL(cb) ((cb).callback = NULL) +#define SET_CALLBACK_TO_NULL(cb) ((cb).callback = NULL, (cb...

This is a combination of these two earlier series: https://www.redhat.com/archives/libguestfs/2019-August/msg00235.html https://www.redhat.com/archives/libguestfs/2019-August/msg00240.html plus changes to allow .callback = NULL / .free != NULL, and to reduce the complexity of freeing callbacks. Although it's rather long there's nothing complex here. We might consider squashing some

...>opt_cb.completion = *complete; + SET_CALLBACK_TO_NULL (*complete); if (nbd_internal_run (h, cmd_issue) == -1) debug (h, "option queued, ignoring state machine failure"); @@ -219,7 +222,9 @@ nbd_unlocked_aio_opt_list (struct nbd_handle *h, nbd_list_callback *list, assert (CALLBACK_IS_NULL (h->opt_cb.fn.list)); h->opt_cb.fn.list = *list; + SET_CALLBACK_TO_NULL (*list); h->opt_cb.completion = *complete; + SET_CALLBACK_TO_NULL (*complete); h->opt_current = NBD_OPT_LIST; if (nbd_internal_run (h, cmd_issue) == -1) debug (h, "option queued, ignoring st...

As promised in my earlier thread on libnbd completion callback question. Eric Blake (2): generator: Refactor handling of closures in unlocked functions generator: Free closures on failure docs/libnbd.pod | 2 +- generator/C.ml | 48 +++++++++++------ generator/C.mli | 1 + lib/debug.c | 7 +-- lib/opt.c | 31 ++++++-----

...- SET_NEXT_STATE (%^OPT_GO.START); - return 0; + if (h->opt_current == NBD_OPT_LIST_META_CONTEXT) { + assert (h->opt_mode); + assert (h->structured_replies); + assert (CALLBACK_IS_NOT_NULL (h->opt_cb.fn.context)); + opt = h->opt_current; + } + else { + assert (CALLBACK_IS_NULL (h->opt_cb.fn.context)); + opt = NBD_OPT_SET_META_CONTEXT; + if (!h->structured_replies || + nbd_internal_string_list_length (h->request_meta_contexts) == 0) { + SET_NEXT_STATE (%^OPT_GO.START); + return 0; + } } assert (h->meta_contexts == NULL); @@ -4...

This is my proposal for fixing the documentation to match practice (namely, that completion.callback is not invoked in the cases where the aio call itself reports errors); we could instead try to go the other direction and tweak the generator to guarantee that both completion.callback and completion.free are reached no matter what, but that felt more invasive to me. Eric Blake (2): api: Tighten

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

...Floor, Boston, MA 02110-1301 USA + */ + +/* State machine for negotiating NBD_OPT_EXTENDED_HEADERS. */ + +STATE_MACHINE { + NEWSTYLE.OPT_EXTENDED_HEADERS.START: + assert (h->gflags & LIBNBD_HANDSHAKE_FLAG_FIXED_NEWSTYLE); + assert (h->opt_current != NBD_OPT_EXTENDED_HEADERS); + assert (CALLBACK_IS_NULL (h->opt_cb.completion)); + if (!h->request_eh || !h->request_sr) { + SET_NEXT_STATE (%^OPT_STRUCTURED_REPLY.START); + return 0; + } + + h->sbuf.option.version = htobe64 (NBD_NEW_VERSION); + h->sbuf.option.option = htobe32 (NBD_OPT_EXTENDED_HEADERS); + h->sbuf.option.op...

...completion_callback *complete) { if ((h->gflags & LIBNBD_HANDSHAKE_FLAG_FIXED_NEWSTYLE) == 0) { set_error (ENOTSUP, "server is not using fixed newstyle protocol"); @@ -218,8 +218,8 @@ nbd_unlocked_aio_opt_list (struct nbd_handle *h, nbd_list_callback list, } assert (CALLBACK_IS_NULL (h->opt_cb.fn.list)); - h->opt_cb.fn.list = list; - h->opt_cb.completion = complete; + h->opt_cb.fn.list = *list; + h->opt_cb.completion = *complete; h->opt_current = NBD_OPT_LIST; if (nbd_internal_run (h, cmd_issue) == -1) debug (h, "option queued, ignoring s...

...me - | OFlags (n, _) -> pr " %s=0x%%x" n + | OFlags (n, _, _) -> pr " %s=0x%%x" n ) optargs; pr "\""; List.iter ( @@ -660,7 +670,7 @@ let generate_lib_api_c () = function | OClosure { cbname } -> pr ", CALLBACK_IS_NULL (%s_callback) ? \"<fun>\" : \"NULL\"" cbname - | OFlags (n, _) -> pr ", %s" n + | OFlags (n, _, _) -> pr ", %s" n ) optargs; pr ");\n"; List.iter ( diff --git a/generator/GoLang.ml b/generator/GoLang.ml ind...

This is version 4 of the following sub-series: [libnbd PATCH v3 09/29] lib/utils: introduce async-signal-safe execvpe() [libnbd PATCH v3 10/29] lib/utils: add unit tests for async-signal-safe execvpe() http://mid.mail-archive.com/20230215141158.2426855-10-lersek at redhat.com http://mid.mail-archive.com/20230215141158.2426855-11-lersek at redhat.com The Notes section on each patch records the

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 ++++++++-

...truct nbd_handle *h, nbd_list_callback list, + nbd_completion_callback complete) +{ + if ((h->gflags & LIBNBD_HANDSHAKE_FLAG_FIXED_NEWSTYLE) == 0) { + set_error (ENOTSUP, "server is not using fixed newstyle protocol"); + return -1; + } + + assert (CALLBACK_IS_NULL (h->opt_cb.fn.list)); + h->opt_cb.fn.list = list; + h->opt_cb.completion = complete; + h->current_opt = NBD_OPT_LIST; + if (nbd_internal_run (h, cmd_issue) == -1) + debug (h, "option queued, ignoring state machine failure"); + return 0; +} diff --git a/tests/newstyle-...

...truct nbd_handle *h, nbd_list_callback list, + nbd_completion_callback complete) +{ + if ((h->gflags & LIBNBD_HANDSHAKE_FLAG_FIXED_NEWSTYLE) == 0) { + set_error (ENOTSUP, "server is not using fixed newstyle protocol"); + return -1; + } + + assert (CALLBACK_IS_NULL (h->opt_cb.fn.list)); + h->opt_cb.fn.list = list; + h->opt_cb.completion = complete; + h->opt_current = NBD_OPT_LIST; + if (nbd_internal_run (h, cmd_issue) == -1) + debug (h, "option queued, ignoring state machine failure"); + return 0; +} diff --git a/python/t/220-op...

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

In v2: - now based on my proposal to add LIBNBD_SHUTDOWN_IMMEDIATE - four flags instead of two: STRICT_FLAGS is new (patch 4), and STRICT_BOUNDS is separate from STRICT_ZERO_SIZE (patch 5) - various refactorings for more shared code and less duplication Eric Blake (5): api: Add xxx_MASK constant for each Flags type generator: Refactor filtering of accepted OFlags api: Add

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.