From patchwork Mon Jun 26 16:08:32 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrey Drobyshev X-Patchwork-Id: 13293112 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 64308EB64DA for ; Mon, 26 Jun 2023 16:09:34 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qDolh-0004D6-P8; Mon, 26 Jun 2023 12:08:45 -0400 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 1qDolf-0004BA-QN; Mon, 26 Jun 2023 12:08:43 -0400 Received: from relay.virtuozzo.com ([130.117.225.111]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qDold-0001gl-9l; Mon, 26 Jun 2023 12:08:43 -0400 Received: from dev005.ch-qa.vzint.dev ([172.29.1.10]) by relay.virtuozzo.com with esmtp (Exim 4.96) (envelope-from ) id 1qDoka-00DiMx-1D; Mon, 26 Jun 2023 18:08:27 +0200 To: qemu-block@nongnu.org, qemu-stable@nongnu.org Cc: qemu-devel@nongnu.org, kwolf@redhat.com, hreitz@redhat.com, vsementsov@yandex-team.ru, eblake@redhat.com, andrey.drobyshev@virtuozzo.com, den@virtuozzo.com Subject: [PATCH 1/3] block: add subcluster_size field to BlockDriverInfo Date: Mon, 26 Jun 2023 19:08:32 +0300 Message-Id: <20230626160834.696680-2-andrey.drobyshev@virtuozzo.com> X-Mailer: git-send-email 2.39.3 In-Reply-To: <20230626160834.696680-1-andrey.drobyshev@virtuozzo.com> References: <20230626160834.696680-1-andrey.drobyshev@virtuozzo.com> MIME-Version: 1.0 Received-SPF: pass client-ip=130.117.225.111; envelope-from=andrey.drobyshev@virtuozzo.com; helo=relay.virtuozzo.com X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham 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: , Reply-to: Andrey Drobyshev X-Patchwork-Original-From: Andrey Drobyshev via From: Andrey Drobyshev Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org This is going to be used in the subsequent commit as requests alignment (in particular, during copy-on-read). This value only makes sense for the formats which support subclusters (currently QCOW2 only). If this field isn't set by driver's own bdrv_get_info() implementation, we simply set it equal to the cluster size thus treating each cluster as having a single subcluster. Signed-off-by: Andrey Drobyshev Reviewed-by: Eric Blake Reviewed-by: Denis V. Lunev --- block.c | 7 +++++++ block/qcow2.c | 1 + include/block/block-common.h | 5 +++++ 3 files changed, 13 insertions(+) diff --git a/block.c b/block.c index 0637265c26..4fe1743cfb 100644 --- a/block.c +++ b/block.c @@ -6392,6 +6392,13 @@ int coroutine_fn bdrv_co_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) } memset(bdi, 0, sizeof(*bdi)); ret = drv->bdrv_co_get_info(bs, bdi); + if (bdi->subcluster_size == 0) { + /* + * If the driver left this unset, subclusters either not supported. + * Then it is safe to treat each cluster as having only one subcluster. + */ + bdi->subcluster_size = bdi->cluster_size; + } if (ret < 0) { return ret; } diff --git a/block/qcow2.c b/block/qcow2.c index e23edd48c2..94b8d0e1c2 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -5197,6 +5197,7 @@ qcow2_co_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) { BDRVQcow2State *s = bs->opaque; bdi->cluster_size = s->cluster_size; + bdi->subcluster_size = s->subcluster_size; bdi->vm_state_offset = qcow2_vm_state_offset(s); bdi->is_dirty = s->incompatible_features & QCOW2_INCOMPAT_DIRTY; return 0; diff --git a/include/block/block-common.h b/include/block/block-common.h index e15395f2cb..df5ffc8d09 100644 --- a/include/block/block-common.h +++ b/include/block/block-common.h @@ -132,6 +132,11 @@ typedef struct BlockZoneWps { typedef struct BlockDriverInfo { /* in bytes, 0 if irrelevant */ int cluster_size; + /* + * A fraction of cluster_size, if supported (currently QCOW2 only); if + * disabled or unsupported, set equal to cluster_size. + */ + int subcluster_size; /* offset at which the VM state can be saved (0 if not possible) */ int64_t vm_state_offset; bool is_dirty;