From patchwork Wed Jan 22 11:50:43 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 13947165 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2706EC02181 for ; Wed, 22 Jan 2025 11:52:22 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1taZGj-0002bs-IG; Wed, 22 Jan 2025 06:51:37 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1taZGi-0002bT-LW for qemu-devel@nongnu.org; Wed, 22 Jan 2025 06:51:36 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1taZGh-00089e-9j for qemu-devel@nongnu.org; Wed, 22 Jan 2025 06:51:36 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1737546694; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Gy0Ro0AiLBW+IDrNU0PGthGke20CO9S9gyVmcl9+x2Q=; b=L0WjAq6OfvA0VZufWy/GvgEvwzFa75cV1aUvwDVNtFvHl9QLjV3EdJBijyyzvKsMzbIQ/j 1ewpX8llUnrO0KItdNDt480vsiR1PNzoHGE/CLiwUhuZVie5rEZwIAvczkBRm39acNN/F3 AZ3ifHqOkzTjAYvAqeAXxSRAdZPQ06Q= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-18-J8PwcvzyMTWf0G5LQ5drow-1; Wed, 22 Jan 2025 06:51:31 -0500 X-MC-Unique: J8PwcvzyMTWf0G5LQ5drow-1 X-Mimecast-MFC-AGG-ID: J8PwcvzyMTWf0G5LQ5drow Received: from mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.40]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 619C0195608B; Wed, 22 Jan 2025 11:51:30 +0000 (UTC) Received: from merkur.fritz.box (unknown [10.39.193.195]) by mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 891AF19560AA; Wed, 22 Jan 2025 11:51:28 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Cc: kwolf@redhat.com, hreitz@redhat.com, pkrempa@redhat.com, peterx@redhat.com, qemu-devel@nongnu.org Subject: [PATCH 6/9] nbd/server: Support inactive nodes Date: Wed, 22 Jan 2025 12:50:43 +0100 Message-ID: <20250122115046.51216-7-kwolf@redhat.com> In-Reply-To: <20250122115046.51216-1-kwolf@redhat.com> References: <20250122115046.51216-1-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.0 on 10.30.177.40 Received-SPF: pass client-ip=170.10.133.124; envelope-from=kwolf@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -51 X-Spam_score: -5.2 X-Spam_bar: ----- X-Spam_report: (-5.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-2.996, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.086, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org In order to support running an NBD export on inactive nodes, we must make sure to return errors for any operations that aren't allowed on inactive nodes. Reads are the only operation we know we need for inactive images, so to err on the side of caution, return errors for everything else, even if some operations could possibly be okay. Signed-off-by: Kevin Wolf --- nbd/server.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/nbd/server.c b/nbd/server.c index f64e47270c..2076fb2666 100644 --- a/nbd/server.c +++ b/nbd/server.c @@ -2026,6 +2026,7 @@ static void nbd_export_delete(BlockExport *blk_exp) const BlockExportDriver blk_exp_nbd = { .type = BLOCK_EXPORT_TYPE_NBD, .instance_size = sizeof(NBDExport), + .supports_inactive = true, .create = nbd_export_create, .delete = nbd_export_delete, .request_shutdown = nbd_export_request_shutdown, @@ -2920,6 +2921,22 @@ static coroutine_fn int nbd_handle_request(NBDClient *client, NBDExport *exp = client->exp; char *msg; size_t i; + bool inactive; + + WITH_GRAPH_RDLOCK_GUARD() { + inactive = bdrv_is_inactive(blk_bs(exp->common.blk)); + if (inactive) { + switch (request->type) { + case NBD_CMD_READ: + /* These commands are allowed on inactive nodes */ + break; + default: + /* Return an error for the rest */ + return nbd_send_generic_reply(client, request, -EPERM, + "export is inactive", errp); + } + } + } switch (request->type) { case NBD_CMD_CACHE: