similar to: [libnbd PATCH] docs: Add libnbd-security(1) man page

Copies heavily after a similar addition recently made in nbdkit. --- I'm not sure if .1 or .3 fits better for the man page. With nbdkit, .1 made sense because 'nbdkit' is a standalone program; but with libnbd, our only standalone is nbdsh, yet naming it nbdsh-security seems off. docs/Makefile.am | 7 +++++++ docs/libnbd-security.pod | 32 ++++++++++++++++++++++++++++++++

On Wed, Sep 11, 2019 at 08:48:28AM -0500, Eric Blake wrote: > On 9/11/19 5:40 AM, Richard W.M. Jones wrote: > > Very much a work in progress as there are still many tests using > > qemu-io which are candidates for conversion. > > > > You'll notice at the end of test-full.sh that the new test has some > > duplicated code which looks as if it ought to be

Instead of having to munge a URI to supply a different export name, we can exploit the fact that nbd_opt_mode lets us change the preferred export name after nbd_connect_uri has established its socket. In fact, by doing this, nbdinfo no longer needs to directly link against libxml2, so it can now be built regardless of whether the underlying libnbd.so supports URIs (although use of the program

A major missing feature of this library was the ability to list exports from an NBD server. This implements the feature by adding a new handle mode and additional functions for querying the list of export names. --- .gitignore | 1 + examples/Makefile.am | 14 +++ examples/list-exports.c | 108 +++++++++++++++++++

We previously needed nbd_add_close_callback to do cleanup from language bindings. However now we have closure lifetimes this is no longer needed and can be removed. See also: https://www.redhat.com/archives/libguestfs/2019-July/msg00213.html --- generator/generator | 18 ------------------ lib/handle.c | 35 ----------------------------------- lib/internal.h | 10 ---------- 3 files

Make it easier for C libraries to consume arbitrary versions of libnbd, by giving a probe for which functions the current version of the library exports. --- I'm fuzzy enough on OCaml that I'll get review for this, although I like the resulting libnbd.h. generator/generator | 24 +++++++++++++++++++++++- 1 file changed, 23 insertions(+), 1 deletion(-) diff --git a/generator/generator

--- .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

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:

The freeing feature can now be done by associating a free callback with a closure's user_data, so having the valid_flag is no longer necessary and it can be completely removed. This mostly reverts commit 2d9b98e96772e282d51dafac07f16387dadc8afa. --- TODO | 2 - docs/libnbd.pod | 64 ++-------------- examples/glib-main-loop.c |

On 7/25/19 8:07 AM, Richard W.M. Jones wrote: > Previously closures had a crude flag which tells if they are > persistent or transient. Transient closures (flag = false) last for > the lifetime of the currently called libnbd function. Persistent > closures had an indefinite lifetime which could last for as long as > the handle. In language bindings handling persistent closures

--- .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

Previously closures had a crude flag which tells if they are persistent or transient. Transient closures (flag = false) last for the lifetime of the currently called libnbd function. Persistent closures had an indefinite lifetime which could last for as long as the handle. In language bindings handling persistent closures was wasteful as we needed to register a "close callback" to

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

This adds a C-only semi-private function for freeing various types of persistent data passed to libnbd. There are some similarities with nbd_add_close_callback which we removed in commit 7f191b150b52ed50098976309a6af883d245fc56. --- generator/generator | 57 ++++++++++++++++++++ lib/Makefile.am | 1 + lib/free.c | 129 ++++++++++++++++++++++++++++++++++++++++++++ lib/handle.c

Also test that the expected environment variable is set when connecting to nbdkit. This test requires nbdkit >= 1.35.2 which added support for -D nbdkit.environ=1 to dump the environment, and will be skipped with other versions. --- .gitignore | 1 + tests/Makefile.am | 8 +++ tests/socket-activation-name.c | 99 ++++++++++++++++++++++++++++++++++ 3 files

--- 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

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

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

With new-enough libnbd and our new dynamic-export mode, we can grab the export list from the server for replay to the client. Signed-off-by: Eric Blake <eblake@redhat.com> --- plugins/nbd/nbdkit-nbd-plugin.pod | 7 ++ tests/Makefile.am | 2 + plugins/nbd/nbd.c | 53 ++++++++++ tests/test-nbd-dynamic-content.sh | 2 +- tests/test-nbd-dynamic-list.sh

Change the way that we deal with freeing closures in language bindings: * The valid_flag is removed (mostly reverting commit 2d9b98e96772e282d51dafac07f16387dadc8afa). * An extra ‘free’ parameter is added to all callback structures. This is called by the library whenever the closure won't be called again (so the user_data can be freed). This is analogous to valid_flag ==