3 # Test preallocated growth of qcow2 images
5 # Copyright (C) 2017 Red Hat, Inc.
7 # This program is free software; you can redistribute it and/or modify
8 # it under the terms of the GNU General Public License as published by
9 # the Free Software Foundation; either version 2 of the License, or
10 # (at your option) any later version.
12 # This program is distributed in the hope that it will be useful,
13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 # GNU General Public License for more details.
17 # You should have received a copy of the GNU General Public License
18 # along with this program. If not, see <http://www.gnu.org/licenses/>.
22 owner
=mreitz@redhat.com
25 echo "QA output created by $seq"
27 status
=1 # failure is the default!
33 trap "_cleanup; exit \$status" 0 1 2 3 15
35 get_image_size_on_host
()
37 echo $
(($
(stat
-c '%b * %B' "$TEST_IMG_FILE")))
40 # get standard environment and filters
47 if [ -z "$TEST_IMG_FILE" ]; then
48 TEST_IMG_FILE
=$TEST_IMG
51 # Test whether we are running on a broken XFS version. There is this
56 # $ block_size=4096 # Your FS's block size
57 # $ fallocate -o $((block_size / 2)) -l $block_size foo
58 # $ LANG=C xfs_bmap foo | grep hole
61 # The problem is that the XFS driver rounds down the offset and
62 # rounds up the length to the block size, but independently. As
63 # such, it only allocates the first block in the example above,
64 # even though it should allocate the first two blocks (because our
65 # request is to fallocate something that touches both the first
68 # This means that when you then write to the beginning of the
69 # second block, the disk usage of the first two blocks grows.
71 # That is precisely what fallocate() promises, though: That when you
72 # write to an area that you have fallocated, no new blocks will have
75 touch "$TEST_IMG_FILE"
76 # Assuming there is no FS with a block size greater than 64k
77 fallocate
-o 65535 -l 2 "$TEST_IMG_FILE"
78 len0
=$
(get_image_size_on_host
)
80 # Write to something that in theory we have just fallocated
81 # (Thus, the on-disk size should not increase)
82 poke_file
"$TEST_IMG_FILE" 65536 42
83 len1
=$
(get_image_size_on_host
)
85 if [ $len1 -gt $len0 ]; then
86 _notrun
"the test filesystem's fallocate() is broken"
89 rm -f "$TEST_IMG_FILE"
91 # Generally, we create some image with or without existing preallocation and
92 # then resize it. Then we write some data into the image and verify that its
93 # size does not change if we have used preallocation.
95 # With a cluster size of 512 B, one L2 table covers 64 * 512 B = 32 kB.
96 # One cluster of the L1 table covers 64 * 32 kB = 2 MB.
97 # There are multiple cases we want to test:
98 # (1) Grow an image without having to allocate a new L2 table.
99 # (2) Grow an image, having to allocate a new L2 table.
100 # (3) Grow an image, having to grow the L1 table.
101 # Therefore, we create an image that is 48 kB below 2 MB. Then:
102 # (1) We resize it to 2 MB - 32 kB. (+ 16 kB)
103 # (2) We resize it to 2 MB. (+ 48 kB)
104 # (3) We resize it to 2 MB + 32 kB. (+ 80 kB)
107 CREATION_SIZE
=$
((2 * 1024 * 1024 - 48 * 1024))
109 # 512 is the actual test -- but it's good to test 64k as well, just to be sure.
110 for cluster_size
in 512 64k
; do
112 for GROWTH_SIZE
in 16 48 80; do
113 for create_mode
in off metadata falloc full
; do
114 for growth_mode
in off metadata falloc full
; do
115 echo "--- cluster_size=$cluster_size growth_size=$GROWTH_SIZE create_mode=$create_mode growth_mode=$growth_mode ---"
117 _make_test_img
-o "preallocation=$create_mode,cluster_size=$cluster_size" ${CREATION_SIZE}
118 $QEMU_IMG resize
-f "$IMGFMT" --preallocation=$growth_mode "$TEST_IMG" +${GROWTH_SIZE}K
120 host_size_0
=$
(get_image_size_on_host
)
121 file_length_0
=$
(stat
-c '%s' "$TEST_IMG_FILE")
123 $QEMU_IO -c "write 0 $CREATION_SIZE" "$TEST_IMG" | _filter_qemu_io
125 host_size_1
=$
(get_image_size_on_host
)
126 file_length_1
=$
(stat
-c '%s' "$TEST_IMG_FILE")
128 $QEMU_IO -c "write $CREATION_SIZE ${GROWTH_SIZE}K" "$TEST_IMG" | _filter_qemu_io
130 host_size_2
=$
(get_image_size_on_host
)
131 file_length_2
=$
(stat
-c '%s' "$TEST_IMG_FILE")
133 # Test creation preallocation: Compare #0 against #1
134 if [ $create_mode != off
]; then
135 # The image length should not have grown
136 if [ $file_length_1 -gt $file_length_0 ]; then
137 echo "ERROR (create): Image length has grown from $file_length_0 to $file_length_1"
139 if [ $create_mode != metadata
]; then
140 # The host size should not have grown either
141 if [ $host_size_1 -gt $host_size_0 ]; then
142 echo "ERROR (create): Host size has grown from $host_size_0 to $host_size_1"
147 # Test resize preallocation: Compare #2 against #1
148 if [ $growth_mode != off
]; then
149 # The image length should not have grown
150 if [ $file_length_2 -gt $file_length_1 ]; then
151 echo "ERROR (grow): Image length has grown from $file_length_1 to $file_length_2"
153 if [ $growth_mode != metadata
]; then
154 # The host size should not have grown either
155 if [ $host_size_2 -gt $host_size_1 ]; then
156 echo "ERROR (grow): Host size has grown from $host_size_1 to $host_size_2"
167 # Test image resizing using preallocation and unaligned offsets
168 $QEMU_IMG create
-f raw
"$TEST_IMG.base" 128k | _filter_img_create
169 $QEMU_IO -c 'write -q -P 1 0 128k' -f raw
"$TEST_IMG.base"
170 for orig_size
in 31k
33k
; do
171 echo "--- Resizing image from $orig_size to 96k ---"
172 _make_test_img
-F raw
-b "$TEST_IMG.base" -o cluster_size
=64k
"$orig_size"
173 $QEMU_IMG resize
-f "$IMGFMT" --preallocation=full
"$TEST_IMG" 96k
174 # The first part of the image should contain data from the backing file
175 $QEMU_IO -c "read -q -P 1 0 ${orig_size}" "$TEST_IMG"
176 # The resized part of the image should contain zeroes
177 $QEMU_IO -c "read -q -P 0 ${orig_size} 63k" "$TEST_IMG"
178 # If the image does not have an external data file we can also verify its
179 # actual size. The resized image should have 7 clusters:
180 # header, L1 table, L2 table, refcount table, refcount block, 2 data clusters
181 if ! _get_data_file
"$TEST_IMG" > /dev
/null
; then
182 expected_file_length
=$
((65536 * 7))
183 file_length
=$
(stat
-c '%s' "$TEST_IMG_FILE")
184 if [ "$file_length" != "$expected_file_length" ]; then
185 echo "ERROR: file length $file_length (expected $expected_file_length)"