From nobody Mon Feb 9 21:36:49 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1501862483127620.8220061478437; Fri, 4 Aug 2017 09:01:23 -0700 (PDT) Received: from localhost ([::1]:50458 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ddf2P-0007Lw-N9 for importer@patchew.org; Fri, 04 Aug 2017 12:01:21 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51179) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ddeFD-0001XL-6l for qemu-devel@nongnu.org; Fri, 04 Aug 2017 11:10:32 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ddeFA-000470-Kn for qemu-devel@nongnu.org; Fri, 04 Aug 2017 11:10:31 -0400 Received: from mailhub.sw.ru ([195.214.232.25]:16486 helo=relay.sw.ru) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ddeFA-00041K-8q for qemu-devel@nongnu.org; Fri, 04 Aug 2017 11:10:28 -0400 Received: from localhost.localdomain (msk-vpn.virtuozzo.com [195.214.232.6]) by relay.sw.ru (8.13.4/8.13.4) with ESMTP id v74FAEtw021861; Fri, 4 Aug 2017 18:10:16 +0300 (MSK) From: "Denis V. Lunev" To: qemu-block@nongnu.org, qemu-devel@nongnu.org Date: Fri, 4 Aug 2017 18:10:11 +0300 Message-Id: <20170804151013.13057-2-den@openvz.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170804151013.13057-1-den@openvz.org> References: <20170804151013.13057-1-den@openvz.org> X-detected-operating-system: by eggs.gnu.org: OpenBSD 3.x [fuzzy] X-Received-From: 195.214.232.25 Subject: [Qemu-devel] [PATCH 1/3] block: respect error code from bdrv_getlength in handle_aiocb_write_zeroes X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , den@openvz.org, Markus Armbruster , Stefan Hajnoczi , Max Reitz Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Original idea beyond the code in question was the following: we have failed to write zeroes with fallocate(FALLOC_FL_ZERO_RANGE) as the simplest approach and via fallocate(FALLOC_FL_PUNCH_HOLE)/fallocate(0). We have the only chance now: if the request comes beyond end of the file. Thus we should calculate file length and respect the error code from that op. Signed-off-by: Denis V. Lunev CC: Markus Armbruster CC: Kevin Wolf CC: Max Reitz CC: Stefan Hajnoczi Reviewed-by: Eric Blake --- block/file-posix.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/block/file-posix.c b/block/file-posix.c index cfbb236f6f..f4de022ae0 100644 --- a/block/file-posix.c +++ b/block/file-posix.c @@ -1339,6 +1339,9 @@ static ssize_t handle_aiocb_write_zeroes(RawPosixAIOD= ata *aiocb) #if defined(CONFIG_FALLOCATE) || defined(CONFIG_XFS) BDRVRawState *s =3D aiocb->bs->opaque; #endif +#ifdef CONFIG_FALLOCATE + int64_t len; +#endif =20 if (aiocb->aio_type & QEMU_AIO_BLKDEV) { return handle_aiocb_write_zeroes_block(aiocb); @@ -1381,7 +1384,10 @@ static ssize_t handle_aiocb_write_zeroes(RawPosixAIO= Data *aiocb) #endif =20 #ifdef CONFIG_FALLOCATE - if (s->has_fallocate && aiocb->aio_offset >=3D bdrv_getlength(aiocb->b= s)) { + /* Last resort: we are trying to extend the file with zeroed data. This + * can be done via fallocate(fd, 0) */ + len =3D bdrv_getlength(aiocb->bs); + if (s->has_fallocate && len >=3D 0 && aiocb->aio_offset >=3D len) { int ret =3D do_fallocate(s->fd, 0, aiocb->aio_offset, aiocb->aio_n= bytes); if (ret =3D=3D 0 || ret !=3D -ENOTSUP) { return ret; --=20 2.11.0