From 79f400ed6efa42347cd551a4a2da3ba1688c431c Mon Sep 17 00:00:00 2001 From: Max Reitz Date: Mon, 18 Jun 2018 18:04:51 +0200 Subject: [PATCH 074/268] iotests: Test post-backing convert target behavior RH-Author: Max Reitz Message-id: <20180618180451.23808-3-mreitz@redhat.com> Patchwork-id: 80797 O-Subject: [RHV-7.6 qemu-kvm-rhev PATCH 2/2] iotests: Test post-backing convert target behavior Bugzilla: 1527898 RH-Acked-by: Stefan Hajnoczi RH-Acked-by: Kevin Wolf RH-Acked-by: Jeffrey Cody This adds a test case to 122 for what happens when you convert to a target with a backing file that is shorter than the target, and the image format does not support efficient zero writes (as is the case with qcow2 v2). Signed-off-by: Max Reitz Message-id: 20180501165750.19242-3-mreitz@redhat.com Reviewed-by: Eric Blake Signed-off-by: Max Reitz (cherry picked from commit 0682854f899d03c78befce9f5aae4a7e37655d25) Signed-off-by: Max Reitz Signed-off-by: Miroslav Rezanina --- tests/qemu-iotests/122 | 42 ++++++++++++++++++++++++++++++++++++++++++ tests/qemu-iotests/122.out | 18 ++++++++++++++++++ 2 files changed, 60 insertions(+) diff --git a/tests/qemu-iotests/122 b/tests/qemu-iotests/122 index 45b359c..d8c8ad7 100755 --- a/tests/qemu-iotests/122 +++ b/tests/qemu-iotests/122 @@ -77,6 +77,48 @@ $QEMU_IO -c "read -P 0 0 3M" "$TEST_IMG".orig 2>&1 | _filter_qemu_io | _filter_t echo +echo "=== Converting to an overlay larger than its backing file ===" +echo + +TEST_IMG="$TEST_IMG".base _make_test_img 256M +# Needs to be at least how much an L2 table covers +# (64 kB/entry * 64 kB / 8 B/entry = 512 MB) +# That way, qcow2 will yield at least two status request responses. +# With just a single response, it would always say "Allocated in the +# backing file", so the optimization qemu-img convert tries to do is +# done automatically. Once it has to be queried twice, however (and +# one of the queries is completely after the end of the backing file), +# the block layer will automatically add a ZERO flag that qemu-img +# convert used to follow up with a zero write to the target. +# We do not want such a zero write, however, because we are past the +# end of the backing file on the target as well, so we do not need to +# write anything there. +_make_test_img -b "$TEST_IMG".base 768M + +# Use compat=0.10 as the output so there is no zero cluster support +$QEMU_IMG convert -O $IMGFMT -B "$TEST_IMG".base -o compat=0.10 \ + "$TEST_IMG" "$TEST_IMG".orig +# See that nothing has been allocated past 64M +$QEMU_IMG map "$TEST_IMG".orig | _filter_qemu_img_map + +echo + +# Just before the end of the backing file +$QEMU_IO -c 'write -P 0x11 255M 1M' "$TEST_IMG".base 2>&1 | _filter_qemu_io +# Somewhere in the second L2 table +$QEMU_IO -c 'write -P 0x22 600M 1M' "$TEST_IMG" 2>&1 | _filter_qemu_io + +$QEMU_IMG convert -O $IMGFMT -B "$TEST_IMG".base -o compat=0.10 \ + "$TEST_IMG" "$TEST_IMG".orig + +$QEMU_IMG map "$TEST_IMG".orig | _filter_qemu_img_map +$QEMU_IO -c 'read -P 0x11 255M 1M' \ + -c 'read -P 0x22 600M 1M' \ + "$TEST_IMG".orig \ + | _filter_qemu_io + + +echo echo "=== Concatenate multiple source images ===" echo diff --git a/tests/qemu-iotests/122.out b/tests/qemu-iotests/122.out index 47d8656..6c7ee1d 100644 --- a/tests/qemu-iotests/122.out +++ b/tests/qemu-iotests/122.out @@ -28,6 +28,24 @@ read 3145728/3145728 bytes at offset 0 read 3145728/3145728 bytes at offset 0 3 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +=== Converting to an overlay larger than its backing file === + +Formatting 'TEST_DIR/t.IMGFMT.base', fmt=IMGFMT size=268435456 +Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=805306368 backing_file=TEST_DIR/t.IMGFMT.base +Offset Length File + +wrote 1048576/1048576 bytes at offset 267386880 +1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +wrote 1048576/1048576 bytes at offset 629145600 +1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +Offset Length File +0xff00000 0x100000 TEST_DIR/t.IMGFMT.base +0x25800000 0x100000 TEST_DIR/t.IMGFMT.orig +read 1048576/1048576 bytes at offset 267386880 +1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +read 1048576/1048576 bytes at offset 629145600 +1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) + === Concatenate multiple source images === Formatting 'TEST_DIR/t.IMGFMT.1', fmt=IMGFMT size=4194304 -- 1.8.3.1