search for: nbd_unlocked_aio_is_processing

...unlocked_poll (h, -1) == -1) return -1; } diff --git a/lib/disconnect.c b/lib/disconnect.c index 6695e59..355a1c9 100644 --- a/lib/disconnect.c +++ b/lib/disconnect.c @@ -29,15 +29,14 @@ int nbd_unlocked_shutdown (struct nbd_handle *h) { - - if (nbd_unlocked_aio_is_ready (h) || - nbd_unlocked_aio_is_processing (h)) { + if (nbd_internal_is_state_ready (h->state) || + nbd_internal_is_state_processing (h->state)) { if (nbd_unlocked_aio_disconnect (h, 0) == -1) return -1; } - while (!nbd_unlocked_aio_is_closed (h) && - !nbd_unlocked_aio_is_dead (h)) { + while (!...

This works. I'm in the middle of testing whether there is any noticable benefit. Rich.

...bd_connection *conn, uint64_t offset, uint64_t count, void *data, int64_t id, extent_fn extent) { - struct command_in_flight *cmd; + struct command_in_flight *cmd, *prev_cmd; + + if (!nbd_unlocked_aio_is_ready (conn) && + !nbd_unlocked_aio_is_processing (conn)) { + set_error (0, "command request %s is invalid in state %s", + nbd_internal_name_of_nbd_cmd (type), + nbd_internal_state_short_string (conn->state)); + return -1; + } switch (type) { /* Commands which send or receive data are limite...

I need to think about this patch series a bit more, but it does at least pass the tests. Rich.

...um state_group group) -{ - switch (group) { - case GROUP_TOP: - return 0; - case GROUP_ISSUE_COMMAND: - case GROUP_REPLY: - return 1; - default: - return is_processing_group (nbd_internal_state_group_parent (group)); - } -} - -/* NB: is_locked = false, may_set_error = false. */ -int -nbd_unlocked_aio_is_processing (struct nbd_handle *h) -{ - enum state_group group = nbd_internal_state_group (h->state); - - return is_processing_group (group); -} - -/* NB: is_locked = false, may_set_error = false. */ -int -nbd_unlocked_aio_is_dead (struct nbd_handle *h) -{ - return h->state == STATE_DEAD; -} - -/* NB:...

...y will let you get rid of the reached_ready flag, as well as making this patch more correct because you probably want to avoid issuing commands on a connection which is closed or dead. You'd use a test like: if (nbd_unlocked_aio_is_ready (conn)) { // call nbd_internal_run } else if (nbd_unlocked_aio_is_processing (conn)) { // can't call nbd_internal_run because we're in the // wrong state, but we can enqueue the command and it // will be processed next time we get to READY } else { // this is an error } > @@ -296,9 +297,24 @@ command_common (struct nbd_connection *conn, &gt...

...ea0 100644 --- a/lib/disconnect.c +++ b/lib/disconnect.c @@ -31,7 +31,8 @@ nbd_unlocked_shutdown (struct nbd_handle *h) size_t i; for (i = 0; i < h->multi_conn; ++i) { - if (nbd_unlocked_aio_is_ready (h->conns[i])) { + if (nbd_unlocked_aio_is_ready (h->conns[i]) || + nbd_unlocked_aio_is_processing (h->conns[i])) { if (nbd_unlocked_aio_disconnect (h->conns[i]) == -1) return -1; } -- 2.20.1

Since v2: - rebase to Rich's new API calls - more refactoring in patch 1 (retitled) - new patches 3 and 4 - fix data corruption in patch 6 (was 4) - more tweaks to the reproducer example (including using new API from 3) Eric Blake (7): lib: Refactor command_common() to do more common work commands: Allow for a command queue commands: Expose FIFO ordering of server completions

...->state)) error_unless_ready() is called while lock is held, so multiple reads of h->state are fine here. > +++ b/lib/disconnect.c > @@ -29,15 +29,14 @@ > int > nbd_unlocked_shutdown (struct nbd_handle *h) > { > - > - if (nbd_unlocked_aio_is_ready (h) || > - nbd_unlocked_aio_is_processing (h)) { > + if (nbd_internal_is_state_ready (h->state) || > + nbd_internal_is_state_processing (h->state)) { Likewise safe for multiple h->state reads. > +/* NB: is_locked = false, may_set_error = false. */ > +int > +nbd_unlocked_aio_is_created (struct nbd_handle *h)...

...state (h)); } /* NB: is_locked = false, may_set_error = false. */ int nbd_unlocked_aio_is_ready (struct nbd_handle *h) { - return nbd_internal_is_state_ready (h->state); + return nbd_internal_is_state_ready (get_state (h)); } /* NB: is_locked = false, may_set_error = false. */ int nbd_unlocked_aio_is_processing (struct nbd_handle *h) { - return nbd_internal_is_state_processing (h->state); + return nbd_internal_is_state_processing (get_state (h)); } /* NB: is_locked = false, may_set_error = false. */ int nbd_unlocked_aio_is_dead (struct nbd_handle *h) { - return nbd_internal_is_state_dead (h-...

This isn't quite finished because not all of the tests or examples have been updated, but it demonstrates an idea: Should we forget about the concept of having multiple connections managed under a single handle? In this patch there is a single ‘struct nbd_handle *’ which manages a single state machine and connection (and therefore no nbd_connection). To connect to a multi-conn server you must

...); } -/* NB: is_locked = false, may_set_error = false. */ int nbd_unlocked_aio_is_ready (struct nbd_handle *h) { - return nbd_internal_is_state_ready (get_state (h)); + return nbd_internal_is_state_ready (get_public_state (h)); } -/* NB: is_locked = false, may_set_error = false. */ int nbd_unlocked_aio_is_processing (struct nbd_handle *h) { - return nbd_internal_is_state_processing (get_state (h)); + return nbd_internal_is_state_processing (get_public_state (h)); } -/* NB: is_locked = false, may_set_error = false. */ int nbd_unlocked_aio_is_dead (struct nbd_handle *h) { - return nbd_internal_is_state...

...); } -/* NB: is_locked = false, may_set_error = false. */ int nbd_unlocked_aio_is_ready (struct nbd_handle *h) { - return nbd_internal_is_state_ready (get_state (h)); + return nbd_internal_is_state_ready (get_public_state (h)); } -/* NB: is_locked = false, may_set_error = false. */ int nbd_unlocked_aio_is_processing (struct nbd_handle *h) { - return nbd_internal_is_state_processing (get_state (h)); + return nbd_internal_is_state_processing (get_public_state (h)); } -/* NB: is_locked = false, may_set_error = false. */ int nbd_unlocked_aio_is_dead (struct nbd_handle *h) { - return nbd_internal_is_state...

v1 was here: https://www.redhat.com/archives/libguestfs/2019-June/thread.html#00055 v2 was here: https://www.redhat.com/archives/libguestfs/2019-June/thread.html#00067 v3: - Fix atomicly -> atomically in commit message. - Fix a comment. - Fix TOCTTOU: There is now an inline function generated called <name>_is_permitted_state, and this is called twice, first outside the

Patch 1/6 was posted before and I didn't change it: https://www.redhat.com/archives/libguestfs/2019-May/thread.html#00134 That doesn't necessarily mean I shouldn't change it, I'm posting it again because the other patches depend on it. The main change in this series is we add three new API functions: nbd_aio_is_created - connection has just been created

On v1, we discussed whether cmds_to_issue needed to be a list, since it never had more than one element. I played with the idea of making it a list, and allowing the client to queue up new commands regardless of whether the state machine is currently in READY. I also polished up the tmp demo into a bit more full-fledged example file, worth including since it also let me discover a hard-to-hit race

RFC because this is an API break, but we haven't declared stable API yet. If we like it, I'm working on using libnbd to implement the nbdkit-nbd plugin; knowing whether it is API version 0.1 or 0.2 will be useful. I also dabbled with allowing optional parameters in python, although my OCaml is weak enough that there may be cleaner ways to approach that. Eric Blake (4): api: Add flags