From patchwork Tue May 23 16:24:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrey Drobyshev X-Patchwork-Id: 13252618 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 D2C57C7EE26 for ; Tue, 23 May 2023 16:26:07 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1q1Up0-0005LI-Cs; Tue, 23 May 2023 12:25:14 -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 1q1Uou-0005JY-QY; Tue, 23 May 2023 12:25:10 -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 1q1Uos-00076p-MR; Tue, 23 May 2023 12:25:08 -0400 Received: from dev005.ch-qa.vzint.dev ([172.29.1.10]) by relay.virtuozzo.com with esmtp (Exim 4.96) (envelope-from ) id 1q1UnN-00DnIw-1X; Tue, 23 May 2023 18:24:48 +0200 To: qemu-block@nongnu.org Cc: qemu-devel@nongnu.org, kwolf@redhat.com, shmuel.eiderman@oracle.com, andrey.drobyshev@virtuozzo.com, den@virtuozzo.com Subject: [PATCH 1/2] qemu-img: rebase: stop when reaching EOF of old backing file Date: Tue, 23 May 2023 19:24:57 +0300 Message-Id: <20230523162458.704266-2-andrey.drobyshev@virtuozzo.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20230523162458.704266-1-andrey.drobyshev@virtuozzo.com> References: <20230523162458.704266-1-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 In case when we're rebasing within one backing chain, and when target image is larger than old backing file, bdrv_is_allocated_above() ends up setting *pnum = 0. As a result, target offset isn't getting incremented, and we get stuck in an infinite for loop. Let's detect this case and break the loop, as there's no more data to be read and merged from the old backing. Signed-off-by: Andrey Drobyshev --- qemu-img.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/qemu-img.c b/qemu-img.c index 27f48051b0..55b6ce407c 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -3813,6 +3813,13 @@ static int img_rebase(int argc, char **argv) strerror(-ret)); goto out; } + if (!n) { + /* + * We've reached EOF of the old backing, therefore there's + * no more mergeable data. + */ + break; + } if (!ret) { continue; } From patchwork Tue May 23 16:24:58 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrey Drobyshev X-Patchwork-Id: 13252617 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 60C44C7EE26 for ; Tue, 23 May 2023 16:25:50 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1q1Uoz-0005Kj-6O; Tue, 23 May 2023 12:25:13 -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 1q1Uov-0005JZ-0f; Tue, 23 May 2023 12:25:10 -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 1q1Uos-00076o-Lc; Tue, 23 May 2023 12:25:08 -0400 Received: from dev005.ch-qa.vzint.dev ([172.29.1.10]) by relay.virtuozzo.com with esmtp (Exim 4.96) (envelope-from ) id 1q1UnN-00DnIw-1h; Tue, 23 May 2023 18:24:48 +0200 To: qemu-block@nongnu.org Cc: qemu-devel@nongnu.org, kwolf@redhat.com, shmuel.eiderman@oracle.com, andrey.drobyshev@virtuozzo.com, den@virtuozzo.com Subject: [PATCH 2/2] qemu-iotests: 024: add rebasing test case for overlay_size > backing_size Date: Tue, 23 May 2023 19:24:58 +0300 Message-Id: <20230523162458.704266-3-andrey.drobyshev@virtuozzo.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20230523162458.704266-1-andrey.drobyshev@virtuozzo.com> References: <20230523162458.704266-1-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 Before previous commit, rebase was getting infitely stuck in case of rebasing within the same backing chain and when overlay_size > backing_size. Let's add this case to the rebasing test 024 to make sure it doesn't break again. Signed-off-by: Andrey Drobyshev --- tests/qemu-iotests/024 | 48 ++++++++++++++++++++++++++++++++++++++ tests/qemu-iotests/024.out | 23 ++++++++++++++++++ 2 files changed, 71 insertions(+) diff --git a/tests/qemu-iotests/024 b/tests/qemu-iotests/024 index 25a564a150..5b6c2d973c 100755 --- a/tests/qemu-iotests/024 +++ b/tests/qemu-iotests/024 @@ -199,6 +199,54 @@ echo # $BASE_OLD and $BASE_NEW) $QEMU_IMG map "$OVERLAY" | _filter_qemu_img_map +# Check that rebase within the chain is working when +# overlay_size > old_backing_size +# +# base_new <-- base_old <-- overlay +# +# Backing (new): 11 11 11 11 +# Backing (old): 22 22 22 22 +# Overlay: -- -- -- -- -- +# +# As a result, overlay should contain data identical to base_old, with the +# last cluster remaining unallocated. + +echo +echo "=== Test rebase within one backing chain ===" +echo + +echo "Creating backing chain" +echo + +TEST_IMG=$BASE_NEW _make_test_img $(( CLUSTER_SIZE * 4 )) +TEST_IMG=$BASE_OLD _make_test_img -b "$BASE_NEW" -F $IMGFMT \ + $(( CLUSTER_SIZE * 4 )) +TEST_IMG=$OVERLAY _make_test_img -b "$BASE_OLD" -F $IMGFMT \ + $(( CLUSTER_SIZE * 5 )) + +echo +echo "Fill backing files with data" +echo + +$QEMU_IO "$BASE_NEW" -c "write -P 0x11 0 $(( CLUSTER_SIZE * 4 ))" \ + | _filter_qemu_io +$QEMU_IO "$BASE_OLD" -c "write -P 0x22 0 $(( CLUSTER_SIZE * 4 ))" \ + | _filter_qemu_io + +echo +echo "Rebase onto another image in the same chain" +echo + +$QEMU_IMG rebase -b "$BASE_NEW" -F $IMGFMT "$OVERLAY" + +# Verify the data is correct +$QEMU_IO "$OVERLAY" -c "read -P 0x22 0 $(( CLUSTER_SIZE * 4 ))" \ + | _filter_qemu_io + +echo + +# Verify that cluster #5 remained unallocated +$QEMU_IMG map "$OVERLAY" | _filter_qemu_img_map # success, all done echo "*** done" diff --git a/tests/qemu-iotests/024.out b/tests/qemu-iotests/024.out index 973a5a3711..fb63cac07c 100644 --- a/tests/qemu-iotests/024.out +++ b/tests/qemu-iotests/024.out @@ -171,4 +171,27 @@ read 65536/65536 bytes at offset 196608 Offset Length File 0 0x30000 TEST_DIR/subdir/t.IMGFMT 0x30000 0x10000 TEST_DIR/subdir/t.IMGFMT.base_new + +=== Test rebase within one backing chain === + +Creating backing chain + +Formatting 'TEST_DIR/subdir/t.IMGFMT.base_new', fmt=IMGFMT size=262144 +Formatting 'TEST_DIR/subdir/t.IMGFMT.base_old', fmt=IMGFMT size=262144 backing_file=TEST_DIR/subdir/t.IMGFMT.base_new backing_fmt=IMGFMT +Formatting 'TEST_DIR/subdir/t.IMGFMT', fmt=IMGFMT size=327680 backing_file=TEST_DIR/subdir/t.IMGFMT.base_old backing_fmt=IMGFMT + +Fill backing files with data + +wrote 262144/262144 bytes at offset 0 +256 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +wrote 262144/262144 bytes at offset 0 +256 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) + +Rebase onto another image in the same chain + +read 262144/262144 bytes at offset 0 +256 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) + +Offset Length File +0 0x40000 TEST_DIR/subdir/t.IMGFMT *** done