similar to: [libnbd PATCH] tests: Make errors more robust under load

Let's check for a quite a few more errors. Among other things, this adds some coverage for a few things I've patched recently. --- And these enhancements set me up for my next fix: making NBD_CMD_DISC prevent future commands. tests/errors.c | 167 +++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 154 insertions(+), 13 deletions(-) diff --git a/tests/errors.c

The original nbd_aio_* (non-callback) functions are removed and replaced with the renamed callback variants. This is a simple mechanical change to the API: (1) Any existing call to nbd_aio_*_callback can simply be renamed to nbd_aio_* (2) Any existing call to nbd_aio_* must have two extra NULL parameters added before the final flags parameter. In non-C languages, only change (1) is

Added merely as an example to be run by hand, rather than automated into 'make check', since nbdkit --filter=noparallel is quite new. --- .gitignore | 1 + examples/Makefile.am | 10 ++ examples/batched-read-write.c | 214 ++++++++++++++++++++++++++++++++++ 3 files changed, 225 insertions(+) create mode 100644 examples/batched-read-write.c diff --git

--- This is what I used to provoke the deadlocks; before my patch series, it was succeeding for a fully-parallel server: nbdkit -U - memory 2M --run './deadlock $unixsocket' as well as for a serialized server that didn't trip up Linux kernel buffering limits: nbdkit -U - --filter=noparallel memory 256k --run './deadlock $unixsocket' but was reliably hanging with both client

The definition of functions that take a callback is changed so that the callback and user_data are combined into a single structure, eg: int64_t nbd_aio_pread (struct nbd_handle *h, void *buf, size_t count, uint64_t offset, - int (*completion_callback) (/*..*/), void *user_data, + nbd_completion_callback completion_callback, uint32_t flags); Several

On Fri, Sep 11, 2020 at 09:31:11AM -0500, Eric Blake wrote: > As mentioned in commits 176fc4ea and 609c25f0, our original plan in > adding a flags argument to nbd_shutdown was to let us specify > different behaviors at the libnbd level, rather than NBD protocol > flags (for that, the user has nbd_aio_disconnect). But when we later > parameterized OFlags to accept various bitmasks

--- .gitignore | 1 + examples/Makefile.am | 12 + examples/concurrent-writer.c | 450 +++++++++++++++++++++++++++++++++++ 3 files changed, 463 insertions(+) diff --git a/.gitignore b/.gitignore index 30438c1..e4dad91 100644 --- a/.gitignore +++ b/.gitignore @@ -41,6 +41,7 @@ Makefile.in /docs/libnbd-api.3 /docs/libnbd-api.pod /examples/batched-read-write

On Thu, Jun 27, 2019 at 10:18:30PM -0500, Eric Blake wrote: > + /* Queue up a write command so large that we block on POLLIN, then queue > + * multiple disconnects. XXX The last one should fail. > + */ > + if (nbd_aio_pwrite (nbd, buf, 2 * 1024 * 1024, 0, 0) == -1) { > + fprintf (stderr, "%s: %s\n", argv[0], nbd_get_error ()); > + exit (EXIT_FAILURE); > +

--- .gitignore | 1 + examples/Makefile.am | 12 + examples/concurrent-writer.c | 450 +++++++++++++++++++++++++++ examples/threaded-reads-and-writes.c | 2 +- 4 files changed, 464 insertions(+), 1 deletion(-) diff --git a/.gitignore b/.gitignore index 30438c1..e4dad91 100644 --- a/.gitignore +++ b/.gitignore @@ -41,6 +41,7 @@ Makefile.in

On 6/30/19 12:54 PM, Richard W.M. Jones wrote: > On Thu, Jun 27, 2019 at 10:18:30PM -0500, Eric Blake wrote: >> + /* Queue up a write command so large that we block on POLLIN, then queue >> + * multiple disconnects. XXX The last one should fail. >> + */ >> + if (nbd_aio_pwrite (nbd, buf, 2 * 1024 * 1024, 0, 0) == -1) { >> + fprintf (stderr, "%s:

Right now, libnbd has refused to issue a command not advertised as supported by a server, including unknown flags, mainly because the NBD protocol does not guarantee what the server will do, and libnbd would rather stay in sync with the server than drop the connection. However, for integration purposes, it can be handy to coerce libnbd into sending something to see how the server will react

As mentioned in commits 176fc4ea and 609c25f0, our original plan in adding a flags argument to nbd_shutdown was to let us specify different behaviors at the libnbd level, rather than NBD protocol flags (for that, the user has nbd_aio_disconnect). But when we later parameterized OFlags to accept various bitmasks (commit f891340b), we failed to mark nbd_shutdown as using a different bitmask than

On Tue, May 30, 2023 at 04:06:32PM +0200, Laszlo Ersek wrote: > On 5/25/23 15:00, Eric Blake wrote: > > Support sending 64-bit requests if extended headers were negotiated. > > This includes setting NBD_CMD_FLAG_PAYLOAD_LEN any time we send an > > extended NBD_CMD_WRITE; this is such a fundamental part of the > > protocol that for now it is easier to silently ignore

Since Eric's improvements to the command queue in commit 6af72b8 (and following) there's now a queue of commands waiting to be issued stored in the handle, and there's no need to issue commands only from the ready state. We can therefore remove the want_to_send logic, queue as many commands as possible, and don't need to test if the socket is ready for POLLOUT. This commit also

Once the client has requested NBD_CMD_DISC, the protocol states that it must not send any further information to the server (further writes may still be needed for a clean TLS shutdown, but that's a different matter requiring more states). Our state machine can prevent some of this if we have moved to CLOSED, but that's not foolproof because we can queue commands that can't be written

The next strict knob: allow the user to pass unknown flags across the wire (this is different than passing a known flag at the wrong time). It is interesting to note that NBD only permits 16 bits of flags, but we have a signature that takes uint32_t; if we wanted, we could pack libnbd-specific flags in the upper bits that the NBD protocol would never see. --- generator/API.ml | 46

On 8/13/19 5:36 PM, Richard W.M. Jones wrote: > The definition of functions that take a callback is changed so that > the callback and user_data are combined into a single structure, eg: > > int64_t nbd_aio_pread (struct nbd_handle *h, > void *buf, size_t count, uint64_t offset, > - int (*completion_callback) (/*..*/), void *user_data, > +

This adds new APIs for running a local NBD server and connecting to it using systemd socket activation (instead of stdin/stdout). This includes interop tests against nbdkit and qemu-nbd which I believe are the only NBD servers supporting socket activation. (If we find others then we can add more interop tests in future.) The upstream spec for systemd socket activation is here:

On Fri, Sep 11, 2020 at 04:49:55PM -0500, Eric Blake wrote: > The next strict knob: allow the user to pass unknown flags across the > wire (this is different than passing a known flag at the wrong time). > > It is interesting to note that NBD only permits 16 bits of flags, but > we have a signature that takes uint32_t; if we wanted, we could pack > libnbd-specific flags in the

On 9/26/19 11:40 AM, Richard W.M. Jones wrote: > This adds new APIs for running a local NBD server and connecting to it > using systemd socket activation (instead of stdin/stdout). > > This includes interop tests against nbdkit and qemu-nbd which I > believe are the only NBD servers supporting socket activation. (If we > find others then we can add more interop tests in