From patchwork Wed Jun 21 12:50:37 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Max Reitz X-Patchwork-Id: 9801765 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 178E76038C for ; Wed, 21 Jun 2017 13:00:18 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id F21742074F for ; Wed, 21 Jun 2017 13:00:17 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E6B2B285DE; Wed, 21 Jun 2017 13:00:17 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 69420285E1 for ; Wed, 21 Jun 2017 13:00:17 +0000 (UTC) Received: from localhost ([::1]:53781 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dNfF2-0007pp-HF for patchwork-qemu-devel@patchwork.kernel.org; Wed, 21 Jun 2017 09:00:16 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:34137) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dNf6o-00089A-C4 for qemu-devel@nongnu.org; Wed, 21 Jun 2017 08:51:47 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dNf6n-0005LH-Ew for qemu-devel@nongnu.org; Wed, 21 Jun 2017 08:51:46 -0400 Received: from mx1.redhat.com ([209.132.183.28]:10134) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dNf6h-0005Go-Qd; Wed, 21 Jun 2017 08:51:40 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id B31DB80F9D; Wed, 21 Jun 2017 12:51:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com B31DB80F9D Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=mreitz@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com B31DB80F9D Received: from localhost (unknown [10.40.205.46]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 88968800CF; Wed, 21 Jun 2017 12:51:36 +0000 (UTC) From: Max Reitz To: qemu-block@nongnu.org Date: Wed, 21 Jun 2017 14:50:37 +0200 Message-Id: <20170621125047.30294-16-mreitz@redhat.com> In-Reply-To: <20170621125047.30294-1-mreitz@redhat.com> References: <20170621125047.30294-1-mreitz@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Wed, 21 Jun 2017 12:51:38 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v5 15/25] block: Use bdrv_dirname() for relative filenames 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 , Alberto Garcia , qemu-devel@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP bdrv_get_full_backing_filename_from_filename() breaks down when it comes to JSON filenames. Using bdrv_dirname() as the basis is better because since we have BDS, we can descend through the BDS tree to the protocol layer, which gives us a greater probability of finding a non-JSON name; also, bdrv_dirname() is more correct as it allows block drivers to override the generation of that directory name in a protocol-specific way. We still need to keep bdrv_get_full_backing_filename_from_filename(), though, because it has valid callers which need it during image creation when no BDS is available yet. This makes a test case in qemu-iotest 110, which was supposed to fail, work. That is actually good, but we need to change the reference output (and the comment in 110) accordingly. Signed-off-by: Max Reitz --- block.c | 20 +++++++++++++++----- tests/qemu-iotests/110 | 3 ++- tests/qemu-iotests/110.out | 2 +- 3 files changed, 18 insertions(+), 7 deletions(-) diff --git a/block.c b/block.c index 0838c12..a5dd6bb 100644 --- a/block.c +++ b/block.c @@ -298,12 +298,22 @@ char *bdrv_get_full_backing_filename_from_filename(const char *backed, static char *bdrv_make_absolute_filename(BlockDriverState *relative_to, const char *filename, Error **errp) { - char *bs_filename = relative_to->exact_filename[0] - ? relative_to->exact_filename - : relative_to->filename; + char *dir, *full_name; - return bdrv_get_full_backing_filename_from_filename(bs_filename, filename, - errp); + if (filename[0] == '\0' || path_has_protocol(filename) || + path_is_absolute(filename)) + { + return g_strdup(filename); + } + + dir = bdrv_dirname(relative_to, errp); + if (!dir) { + return NULL; + } + + full_name = g_strconcat(dir, filename, NULL); + g_free(dir); + return full_name; } char *bdrv_get_full_backing_filename(BlockDriverState *bs, Error **errp) diff --git a/tests/qemu-iotests/110 b/tests/qemu-iotests/110 index 9de7369..ba1b3c6 100755 --- a/tests/qemu-iotests/110 +++ b/tests/qemu-iotests/110 @@ -61,7 +61,8 @@ echo '=== Non-reconstructable filename ===' echo # Across blkdebug without a config file, you cannot reconstruct filenames, so -# qemu is incapable of knowing the directory of the top image +# qemu is incapable of knowing the directory of the top image from the filename +# alone. However, using bdrv_dirname(), it should still work. TEST_IMG="json:{ 'driver': '$IMGFMT', 'file': { diff --git a/tests/qemu-iotests/110.out b/tests/qemu-iotests/110.out index b3584ff..5370bc1 100644 --- a/tests/qemu-iotests/110.out +++ b/tests/qemu-iotests/110.out @@ -14,7 +14,7 @@ backing file: t.IMGFMT.base (actual path: TEST_DIR/t.IMGFMT.base) image: json:{"driver": "IMGFMT", "file": {"set-state.0.event": "read_aio", "image": {"driver": "file", "filename": "TEST_DIR/t.IMGFMT"}, "driver": "blkdebug", "set-state.0.new_state": 42}} file format: IMGFMT virtual size: 64M (67108864 bytes) -backing file: t.IMGFMT.base (cannot determine actual path) +backing file: t.IMGFMT.base (actual path: TEST_DIR/t.IMGFMT.base) === Backing name is always relative to the backed image ===