1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
|
#!/bin/bash
# This documents the state of things as of 4.12-rc4.
#
# - fallocate -z deallocates because BLKDEV_ZERO_NOUNMAP hint is ignored by
# krbd
#
# - unaligned fallocate -z/-p appear to not deallocate -- see caveat #2 in
# linux.git commit 6ac56951dc10 ("rbd: implement REQ_OP_WRITE_ZEROES")
set -ex
# no blkdiscard(8) in trusty
function py_blkdiscard() {
local offset=$1
python <<EOF
import fcntl, struct
BLKDISCARD = 0x1277
with open('$DEV', 'w') as dev:
fcntl.ioctl(dev, BLKDISCARD, struct.pack('QQ', $offset, $IMAGE_SIZE - $offset))
EOF
}
# fallocate(1) in trusty doesn't support -z/-p
function py_fallocate() {
local mode=$1
local offset=$2
python <<EOF
import os, ctypes, ctypes.util
FALLOC_FL_KEEP_SIZE = 0x01
FALLOC_FL_PUNCH_HOLE = 0x02
FALLOC_FL_ZERO_RANGE = 0x10
libc = ctypes.CDLL(ctypes.util.find_library('c'), use_errno=True)
with open('$DEV', 'w') as dev:
if libc.fallocate(dev.fileno(), ctypes.c_int($mode), ctypes.c_long($offset), ctypes.c_long($IMAGE_SIZE - $offset)):
err = ctypes.get_errno()
raise OSError(err, os.strerror(err))
EOF
}
function allocate() {
xfs_io -c "pwrite -b $OBJECT_SIZE -W 0 $IMAGE_SIZE" $DEV
cmp <(od -xAx $DEV) - <<EOF
000000 cdcd cdcd cdcd cdcd cdcd cdcd cdcd cdcd
*
$(printf %x $IMAGE_SIZE)
EOF
[[ $(rados -p rbd ls | grep -c rbd_data.$IMAGE_ID) -eq $NUM_OBJECTS ]]
}
function assert_deallocated() {
cmp <(od -xAx $DEV) - <<EOF
000000 0000 0000 0000 0000 0000 0000 0000 0000
*
$(printf %x $IMAGE_SIZE)
EOF
[[ $(rados -p rbd ls | grep -c rbd_data.$IMAGE_ID) -eq 0 ]]
}
function assert_deallocated_unaligned() {
local num_objects_expected=$1
cmp <(od -xAx $DEV) - <<EOF
000000 cdcd cdcd cdcd cdcd cdcd cdcd cdcd cdcd
*
$(printf %x $((OBJECT_SIZE / 2))) 0000 0000 0000 0000 0000 0000 0000 0000
*
$(printf %x $IMAGE_SIZE)
EOF
[[ $(rados -p rbd ls | grep -c rbd_data.$IMAGE_ID) -eq $num_objects_expected ]]
for ((i = 0; i < $num_objects_expected; i++)); do
rados -p rbd stat rbd_data.$IMAGE_ID.$(printf %016x $i) | grep "size $((OBJECT_SIZE / 2))"
done
}
IMAGE_NAME="fallocate-test"
rbd create --size 200 $IMAGE_NAME
IMAGE_SIZE=$(rbd info --format=json $IMAGE_NAME | python -c 'import sys, json; print json.load(sys.stdin)["size"]')
OBJECT_SIZE=$(rbd info --format=json $IMAGE_NAME | python -c 'import sys, json; print json.load(sys.stdin)["object_size"]')
NUM_OBJECTS=$((IMAGE_SIZE / OBJECT_SIZE))
[[ $((IMAGE_SIZE % OBJECT_SIZE)) -eq 0 ]]
IMAGE_ID="$(rbd info --format=json $IMAGE_NAME |
python -c "import sys, json; print json.load(sys.stdin)['block_name_prefix'].split('.')[1]")"
DEV=$(sudo rbd map $IMAGE_NAME)
# blkdev_issue_discard
allocate
py_blkdiscard 0
assert_deallocated
# blkdev_issue_zeroout w/ BLKDEV_ZERO_NOUNMAP
allocate
py_fallocate FALLOC_FL_ZERO_RANGE\|FALLOC_FL_KEEP_SIZE 0
assert_deallocated
# blkdev_issue_zeroout w/ BLKDEV_ZERO_NOFALLBACK
allocate
py_fallocate FALLOC_FL_PUNCH_HOLE\|FALLOC_FL_KEEP_SIZE 0
assert_deallocated
# unaligned blkdev_issue_discard
allocate
py_blkdiscard $((OBJECT_SIZE / 2))
assert_deallocated_unaligned 1
# unaligned blkdev_issue_zeroout w/ BLKDEV_ZERO_NOUNMAP
allocate
py_fallocate FALLOC_FL_ZERO_RANGE\|FALLOC_FL_KEEP_SIZE $((OBJECT_SIZE / 2))
assert_deallocated_unaligned $NUM_OBJECTS
# unaligned blkdev_issue_zeroout w/ BLKDEV_ZERO_NOFALLBACK
allocate
py_fallocate FALLOC_FL_PUNCH_HOLE\|FALLOC_FL_KEEP_SIZE $((OBJECT_SIZE / 2))
assert_deallocated_unaligned $NUM_OBJECTS
sudo rbd unmap $DEV
echo OK
|
