From db2a380c84574d8c76d7193b8af8535234fe5156 Mon Sep 17 00:00:00 2001 From: Eric Blake Date: Tue, 17 Mar 2020 15:17:10 -0500 Subject: net: Complete qapi-fication of netdev_add We've had all the required pieces for doing a type-safe representation of netdev_add as a flat union for quite some time now (since 0e55c381f6 in v2.7.0, released in 2016), but did not make the final switch to using it because of concern about whether a command-line regression in accepting "1" in place of 1 for integer arguments would be problematic. Back then, we did not have the deprecation cycle to allow us to make progress. But now that we have waited so long, other problems have crept in: for example, our desire to add qemu-storage-daemon is hampered by the inability to express net objects, and we are unable to introspect what we actually accept. Additionally, our round-trip through QemuOpts silently eats any argument that expands to an array, rendering dnssearch, hostfwd, and guestfwd useless through QMP: {"execute": "netdev_add", "arguments": { "id": "netdev0", "type": "user", "dnssearch": [ { "str": "8.8.8.8" }, { "str": "8.8.4.4" } ]}} So without further ado, let's turn on proper QAPI. netdev_add() was a trivial wrapper around net_client_init(), which did a few steps prior to calling net_client_init1(); with this patch, we now skip directly to net_client_init1(). In addition to fixing array parameters, the following additional differences occur: - {"execute": "netdev_add", "arguments": {"type": "help"}} no longer attempts to print help to stdout and exit. Bug fix, broken in 547203ead4 'net: List available netdevs with "-netdev help"', v2.12.0. - {"execute": "netdev_add", "arguments': {... "ipv6-net": "..." }} no longer attempts to desugar the undocumented ipv6-net magic string into the proper "ipv6-prefix" and "ipv6-prefixlen". Undocumented misfeature, introduced in commit 7aac531ef2 "qapi-schema, qemu-options & slirp: Adding Qemu options for IPv6 addresses", v2.6.0. - {'execute':'netdev_add', 'arguments':{'id':'net2', 'type':'hubport', 'hubid':"2"}} {"error": {"class": "GenericError", "desc": "Invalid parameter type for 'hubid', expected: integer"}} Used to succeed: since our command line treats everything as strings, our not-so-round-trip conversion from QAPI -> QemuOpts -> QAPI lost the original typing and turned everything into a string; now that we skip the QemuOpts, the JSON input has to match the exact QAPI type. But this stricter QMP is desirable, and introspection is sufficient for any affected applications to make sure they use it correctly. In qmp_netdev_add(), we still have to create a QemuOpts object so that qmp_netdev_del() will be able to remove a hotplugged network device; but the opts->head remains empty since we now manage all parsing through the QAPI object rather than QemuOpts; a separate patch will address the abuse of QemuOpts as a witness for whether a NetClientState is a netdev. In the meantime, our argument that we are okay requires auditing all uses of option group "netdev": - qemu_netdev_opts: option group definition, empty .desc[] - CLI (CLI netdev parsing ends before monitors start, so while monitors can mess with CLI netdevs, CLI cannot mess with monitor netdevs): - main() case QEMU_OPTION_netdev: store CLI definition - main() case QEMU_OPTION_readconfig, case QEMU_OPTION_writeconfig: similar, dealing only with CLI - net_init_clients(): Pass CLI to net_client_init() - Monitor: - hmp_netdev_add(): straightforward parse into net_client_init() - qmp_netdev_add(): subject of this patch, used to add full object to option group, now just adds bare-bones id - qmp_netdev_del(), netdev_del_completion(): check the option group solely for id, as a 'is this a netdev' predicate Reported-by: Alex Kirillov Signed-off-by: Eric Blake Message-Id: <20200317201711.322764-2-eblake@redhat.com> Reviewed-by: Markus Armbruster [Commit message typo fixed] Signed-off-by: Markus Armbruster --- net/net.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'net') diff --git a/net/net.c b/net/net.c index 9e93c3f..a2065aa 100644 --- a/net/net.c +++ b/net/net.c @@ -1170,7 +1170,7 @@ void netdev_add(QemuOpts *opts, Error **errp) net_client_init(opts, true, errp); } -void qmp_netdev_add(QDict *qdict, QObject **ret, Error **errp) +void qmp_netdev_add(Netdev *netdev, Error **errp) { Error *local_err = NULL; QemuOptsList *opts_list; @@ -1181,12 +1181,12 @@ void qmp_netdev_add(QDict *qdict, QObject **ret, Error **errp) goto out; } - opts = qemu_opts_from_qdict(opts_list, qdict, &local_err); + opts = qemu_opts_create(opts_list, netdev->id, 1, &local_err); if (local_err) { goto out; } - netdev_add(opts, &local_err); + net_client_init1(netdev, true, &local_err); if (local_err) { qemu_opts_del(opts); goto out; -- cgit v1.1 From 08712fcb851034228b61f75bd922863a984a4f60 Mon Sep 17 00:00:00 2001 From: Eric Blake Date: Tue, 17 Mar 2020 15:17:11 -0500 Subject: net: Track netdevs in NetClientState rather than QemuOpt As mentioned in the previous patch, our use of QemuOpt group "netdev" has two purposes: collect the CLI arguments, and serve as a witness for monitor hotplug actions. As the latter didn't use anything but an id, it felt rather unclean to have to touch QemuOpts at all when going through QMP, so let's instead track things with a bool field in NetClientState. Suggested-by: Markus Armbruster Signed-off-by: Eric Blake Message-Id: <20200317201711.322764-3-eblake@redhat.com> Reviewed-by: Markus Armbruster Signed-off-by: Markus Armbruster --- net/net.c | 37 +++++++++++-------------------------- 1 file changed, 11 insertions(+), 26 deletions(-) (limited to 'net') diff --git a/net/net.c b/net/net.c index a2065aa..38778e8 100644 --- a/net/net.c +++ b/net/net.c @@ -1060,6 +1060,15 @@ static int net_client_init1(const void *object, bool is_netdev, Error **errp) } return -1; } + + if (is_netdev) { + NetClientState *nc; + + nc = qemu_find_netdev(netdev->id); + assert(nc); + nc->is_netdev = true; + } + return 0; } @@ -1172,34 +1181,12 @@ void netdev_add(QemuOpts *opts, Error **errp) void qmp_netdev_add(Netdev *netdev, Error **errp) { - Error *local_err = NULL; - QemuOptsList *opts_list; - QemuOpts *opts; - - opts_list = qemu_find_opts_err("netdev", &local_err); - if (local_err) { - goto out; - } - - opts = qemu_opts_create(opts_list, netdev->id, 1, &local_err); - if (local_err) { - goto out; - } - - net_client_init1(netdev, true, &local_err); - if (local_err) { - qemu_opts_del(opts); - goto out; - } - -out: - error_propagate(errp, local_err); + net_client_init1(netdev, true, errp); } void qmp_netdev_del(const char *id, Error **errp) { NetClientState *nc; - QemuOpts *opts; nc = qemu_find_netdev(id); if (!nc) { @@ -1208,14 +1195,12 @@ void qmp_netdev_del(const char *id, Error **errp) return; } - opts = qemu_opts_find(qemu_find_opts_err("netdev", NULL), id); - if (!opts) { + if (!nc->is_netdev) { error_setg(errp, "Device '%s' is not a netdev", id); return; } qemu_del_net_client(nc); - qemu_opts_del(opts); } static void netfilter_print_info(Monitor *mon, NetFilterState *nf) -- cgit v1.1