From mboxrd@z Thu Jan 1 00:00:00 1970 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 75227C54E58 for ; Fri, 15 Mar 2024 09:19:47 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rl3iM-0003K7-SN; Fri, 15 Mar 2024 05:18:58 -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 1rl3iL-0003I6-Uc for qemu-devel@nongnu.org; Fri, 15 Mar 2024 05:18:57 -0400 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 1rl3iK-0000YF-9E for qemu-devel@nongnu.org; Fri, 15 Mar 2024 05:18:57 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1710494335; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=j5PWWCTUbve5HZqg5gNONsxDza5Z88BZwyMjQ/11dZc=; b=GgiA4wJGaSPX5v4j/sjwFsjEz3P8sNTr0IkGrKyqnDNin89JCbfsZJP+DSe9Fr/9B9Vaxu 32pJtBChQ6u3kGNm1S4pcy4Te5czUwJr58DMCxKwSPwctFtcV6O8WtQU2tF8KS83LGZef6 gO8Pc9JF0hdk9Y6nKNi5nUqoW/t8eZ8= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-226-B1AxVKRlOpWVefx_8aUj9A-1; Fri, 15 Mar 2024 05:18:52 -0400 X-MC-Unique: B1AxVKRlOpWVefx_8aUj9A-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (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 mimecast-mx02.redhat.com (Postfix) with ESMTPS id 1017B3C0D7BD; Fri, 15 Mar 2024 09:18:52 +0000 (UTC) Received: from redhat.com (unknown [10.42.28.78]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 86CDF10E4B; Fri, 15 Mar 2024 09:18:50 +0000 (UTC) Date: Fri, 15 Mar 2024 09:18:48 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Alexander Ivanov Cc: qemu-devel@nongnu.org, qemu-block@nongnu.org, den@virtuozzo.com, andrey.drobyshev@virtuozzo.com, jsnow@redhat.com, vsementsov@yandex-team.ru, kwolf@redhat.com, hreitz@redhat.com Subject: Re: [PATCH v3] block: Use LVM tools for LV block device truncation Message-ID: References: <20240315085838.226506-1-alexander.ivanov@virtuozzo.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20240315085838.226506-1-alexander.ivanov@virtuozzo.com> User-Agent: Mutt/2.2.12 (2023-09-09) X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.5 Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -30 X-Spam_score: -3.1 X-Spam_bar: --- X-Spam_report: (-3.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.987, 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_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 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: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Fri, Mar 15, 2024 at 09:58:38AM +0100, Alexander Ivanov wrote: > If a block device is an LVM logical volume we can resize it using > standard LVM tools. > > Add a helper to detect if a device is a DM device. In raw_co_truncate() > check if the block device is DM and resize it executing lvresize. > > Signed-off-by: Alexander Ivanov > --- > block/file-posix.c | 61 ++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 61 insertions(+) Reviewed-by: Daniel P. Berrangé > > diff --git a/block/file-posix.c b/block/file-posix.c > index 35684f7e21..af17a43fe9 100644 > --- a/block/file-posix.c > +++ b/block/file-posix.c > @@ -2642,6 +2642,38 @@ raw_regular_truncate(BlockDriverState *bs, int fd, int64_t offset, > return raw_thread_pool_submit(handle_aiocb_truncate, &acb); > } > > +static bool device_is_dm(struct stat *st) > +{ > + unsigned int maj, maj2; > + char line[32], devname[16]; > + bool ret = false; > + FILE *f; > + > + if (!S_ISBLK(st->st_mode)) { > + return false; > + } > + > + f = fopen("/proc/devices", "r"); > + if (!f) { > + return false; > + } > + > + maj = major(st->st_rdev); > + > + while (fgets(line, sizeof(line), f)) { > + if (sscanf(line, "%u %15s", &maj2, devname) != 2) { > + continue; > + } > + if (strcmp(devname, "device-mapper") == 0) { > + ret = (maj == maj2); > + break; > + } > + } > + > + fclose(f); > + return ret; > +} > + > static int coroutine_fn raw_co_truncate(BlockDriverState *bs, int64_t offset, > bool exact, PreallocMode prealloc, > BdrvRequestFlags flags, Error **errp) > @@ -2670,6 +2702,35 @@ static int coroutine_fn raw_co_truncate(BlockDriverState *bs, int64_t offset, > if (S_ISCHR(st.st_mode) || S_ISBLK(st.st_mode)) { > int64_t cur_length = raw_getlength(bs); > > + /* > + * Try to resize an LVM device using LVM tools. > + */ > + if (device_is_dm(&st) && offset > 0) { > + int spawn_flags = G_SPAWN_SEARCH_PATH | G_SPAWN_STDOUT_TO_DEV_NULL; > + int status; > + bool success; > + char *err; > + GError *gerr = NULL, *gerr_exit = NULL; > + g_autofree char *size_str = g_strdup_printf("%" PRId64 "B", offset); > + const char *cmd[] = {"lvresize", "-f", "-L", > + size_str, bs->filename, NULL}; > + > + success = g_spawn_sync(NULL, (gchar **)cmd, NULL, spawn_flags, > + NULL, NULL, NULL, &err, &status, &gerr); > + > + if (success && g_spawn_check_exit_status(status, &gerr_exit)) { > + return 0; > + } > + > + if (success) { > + error_setg(errp, "%s: %s", gerr_exit->message, err); > + } else { > + error_setg(errp, "lvresize execution error: %s", gerr->message); > + } > + > + return -EINVAL; > + } > + > if (offset != cur_length && exact) { > error_setg(errp, "Cannot resize device files"); > return -ENOTSUP; > -- > 2.40.1 > > With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|