3 # This documents the state of things as of 4.12-rc4.
5 # - fallocate -z deallocates because BLKDEV_ZERO_NOUNMAP hint is ignored by
8 # - unaligned fallocate -z/-p appear to not deallocate -- see caveat #2 in
9 # linux.git commit 6ac56951dc10 ("rbd: implement REQ_OP_WRITE_ZEROES")
13 # no blkdiscard(8) in trusty
14 function py_blkdiscard() {
20 with open('$DEV', 'w') as dev:
21 fcntl.ioctl(dev, BLKDISCARD, struct.pack('QQ', $offset, $IMAGE_SIZE - $offset))
25 # fallocate(1) in trusty doesn't support -z/-p
26 function py_fallocate() {
31 import os, ctypes, ctypes.util
32 FALLOC_FL_KEEP_SIZE = 0x01
33 FALLOC_FL_PUNCH_HOLE = 0x02
34 FALLOC_FL_ZERO_RANGE = 0x10
35 libc = ctypes.CDLL(ctypes.util.find_library('c'), use_errno=True)
36 with open('$DEV', 'w') as dev:
37 if libc.fallocate(dev.fileno(), ctypes.c_int($mode), ctypes.c_long($offset), ctypes.c_long($IMAGE_SIZE - $offset)):
38 err = ctypes.get_errno()
39 raise OSError(err, os.strerror(err))
44 xfs_io -c "pwrite -b $OBJECT_SIZE -W 0 $IMAGE_SIZE" $DEV
45 cmp <(od -xAx $DEV) - <<EOF
46 000000 cdcd cdcd cdcd cdcd cdcd cdcd cdcd cdcd
48 $(printf %x $IMAGE_SIZE)
50 [[ $(rados -p rbd ls | grep -c rbd_data.$IMAGE_ID) -eq $NUM_OBJECTS ]]
53 function assert_deallocated() {
54 cmp <(od -xAx $DEV) - <<EOF
55 000000 0000 0000 0000 0000 0000 0000 0000 0000
57 $(printf %x $IMAGE_SIZE)
59 [[ $(rados -p rbd ls | grep -c rbd_data.$IMAGE_ID) -eq 0 ]]
62 function assert_deallocated_unaligned() {
63 local num_objects_expected=$1
65 cmp <(od -xAx $DEV) - <<EOF
66 000000 cdcd cdcd cdcd cdcd cdcd cdcd cdcd cdcd
68 $(printf %x $((OBJECT_SIZE / 2))) 0000 0000 0000 0000 0000 0000 0000 0000
70 $(printf %x $IMAGE_SIZE)
72 [[ $(rados -p rbd ls | grep -c rbd_data.$IMAGE_ID) -eq $num_objects_expected ]]
73 for ((i = 0; i < $num_objects_expected; i++)); do
74 rados -p rbd stat rbd_data.$IMAGE_ID.$(printf %016x $i) | grep "size $((OBJECT_SIZE / 2))"
78 IMAGE_NAME="fallocate-test"
80 rbd create --size 200 $IMAGE_NAME
82 IMAGE_SIZE=$(rbd info --format=json $IMAGE_NAME | python -c 'import sys, json; print json.load(sys.stdin)["size"]')
83 OBJECT_SIZE=$(rbd info --format=json $IMAGE_NAME | python -c 'import sys, json; print json.load(sys.stdin)["object_size"]')
84 NUM_OBJECTS=$((IMAGE_SIZE / OBJECT_SIZE))
85 [[ $((IMAGE_SIZE % OBJECT_SIZE)) -eq 0 ]]
87 IMAGE_ID="$(rbd info --format=json $IMAGE_NAME |
88 python -c "import sys, json; print json.load(sys.stdin)['block_name_prefix'].split('.')[1]")"
90 DEV=$(sudo rbd map $IMAGE_NAME)
92 # blkdev_issue_discard
97 # blkdev_issue_zeroout w/ BLKDEV_ZERO_NOUNMAP
99 py_fallocate FALLOC_FL_ZERO_RANGE\|FALLOC_FL_KEEP_SIZE 0
102 # blkdev_issue_zeroout w/ BLKDEV_ZERO_NOFALLBACK
104 py_fallocate FALLOC_FL_PUNCH_HOLE\|FALLOC_FL_KEEP_SIZE 0
107 # unaligned blkdev_issue_discard
109 py_blkdiscard $((OBJECT_SIZE / 2))
110 assert_deallocated_unaligned 1
112 # unaligned blkdev_issue_zeroout w/ BLKDEV_ZERO_NOUNMAP
114 py_fallocate FALLOC_FL_ZERO_RANGE\|FALLOC_FL_KEEP_SIZE $((OBJECT_SIZE / 2))
115 assert_deallocated_unaligned $NUM_OBJECTS
117 # unaligned blkdev_issue_zeroout w/ BLKDEV_ZERO_NOFALLBACK
119 py_fallocate FALLOC_FL_PUNCH_HOLE\|FALLOC_FL_KEEP_SIZE $((OBJECT_SIZE / 2))
120 assert_deallocated_unaligned $NUM_OBJECTS