This test cases checks data integrity of raid5 write back cache
under various scenarios:
degraded mode, non-overwrite, raid-5/6.
Signed-off-by: Song Liu <redacted>
---
tests/21raid5cache | 87 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 87 insertions(+)
create mode 100644 tests/21raid5cache
diff --git a/tests/21raid5cache b/tests/21raid5cache
new file mode 100644
index 0000000..0dd97bf
--- /dev/null
+++ b/tests/21raid5cache
@@ -0,0 +1,87 @@
+# check data integrity with raid5 write back cache
+
+# create a 4kB random file and 4 files each with a 1kB chunk of the random file:
+# randfile: ABCD randchunk[0-3]: A B C D
+#
+# then create another random 1kB chunk E, and a new random page with A, B, E, D:
+# randchunk4: E newrandfile: ABED
+create_random_data() {
+ dd if=/dev/urandom of=/tmp/randfile bs=4k count=1
+ for x in {0..3}
+ do
+ dd if=/tmp/randfile of=/tmp/randchunk$x bs=1k count=1 skip=$x count=1
+ done
+
+ dd if=/dev/urandom of=/tmp/randchunk4 bs=1k count=1
+
+ rm /tmp/newrandfile
+ for x in 0 1 4 3
+ do
+ cat /tmp/randchunk$x >> /tmp/newrandfile
+ done
+}
+
+# create array, $1 could be 5 for raid5 and 6 for raid6
+create_array() {
+ if [ $1 -lt 5 -o $1 -gt 6 ]
+ then
+ echo wrong array type $1
+ exit 2
+ fi
+
+ mdadm -CR $md0 -c4 -l5 -n10 $dev0 $dev1 $dev2 $dev3 $dev4 $dev5 $dev6 $dev11 $dev8 $dev9 --write-journal $dev10
+ check wait
+ echo write-back > /sys/block/md0/md/journal_mode
+}
+
+restart_array_write_back() {
+ mdadm -S $md0
+ mdadm -A $md0 $dev0 $dev1 $dev2 $dev3 $dev4 $dev5 $dev6 $dev11 $dev8 $dev9 $dev10
+ echo write-back > /sys/block/md0/md/journal_mode
+}
+
+# compare the first page of md0 with file in $1
+cmp_first_page() {
+ cmp -n 4096 $1 $md0 || { echo cmp failed ; exit 2 ; }
+}
+
+# write 3 pages after the first page of md0
+write_three_pages() {
+ for x in {1..3}
+ do
+ dd if=/dev/urandom of=$md0 bs=4k count=1 seek=$x count=1
+ done
+}
+
+# run_test <array_type:5/6> <degraded_or_not:yes/no>
+run_test() {
+ create_random_data
+ create_array $1
+
+ if [ $2 == yes ]
+ then
+ mdadm --fail $md0 $dev0
+ fi
+
+ dd if=/tmp/randfile of=$md0 bs=4k count=1
+ restart_array_write_back
+ cmp_first_page /tmp/randfile
+ restart_array_write_back
+ write_three_pages
+ cmp_first_page /tmp/randfile
+
+
+ dd if=/tmp/randchunk4 of=/dev/md0 bs=1k count=1 seek=2
+ restart_array_write_back
+ cmp_first_page /tmp/newrandfile
+ restart_array_write_back
+ write_three_pages
+ cmp_first_page /tmp/newrandfile
+
+ mdadm -S $md0
+}
+
+run_test 5 no
+run_test 5 yes
+run_test 6 no
+run_test 6 yes--
2.9.3