Add mkdir-rename-rmdir test

Add a test which performs mkdir, two renames of the dir, and rmdir on
all possible combinations of mounts.

Signed-off-by: Zach Brown <zab@versity.com>

tests/sequence

@@ -21,6 +21,7 @@ stage-multi-part.sh
 stage-tmpfile.sh
 basic-posix-consistency.sh
 dirent-consistency.sh
+mkdir-rename-rmdir.sh
 lock-ex-race-processes.sh
 lock-conflicting-batch-commit.sh
 cross-mount-data-free.sh

tests/tests/mkdir-rename-rmdir.sh

@@ -0,0 +1,59 @@
+#
+# Sequentially perform operations on a dir (mkdir; rename*2; rmdir) on
+# all possible combinations of different mounts that could perform the
+# operations.
+#
+# We're testing that the tracking of the entry key in our cached dirents
+# stays consitent with the persistent entry items as they're modified
+# around the cluster.
+#
+
+t_require_commands mkdir mv rmdir
+
+NR_OPS=4
+
+unset op_mnt
+for op in $(seq 0 $NR_OPS); do
+	op_mnt[$op]=0
+done
+
+if [ $T_NR_MOUNTS -gt $NR_OPS ]; then
+	NR_MNTS=$NR_OPS
+else
+	NR_MNTS=$T_NR_MOUNTS
+fi
+
+# test until final op mount dir wraps
+while [ ${op_mnt[$NR_OPS]} == 0 ]; do
+
+	# sequentially perform each op from its mount dir
+	for op in $(seq 0 $((NR_OPS - 1))); do
+		m=${op_mnt[$op]}
+		eval dir="\$T_D${m}/dir"
+
+		case "$op" in
+			0) mkdir "$dir" ;;
+			1) mv "$dir" "$dir-1" ;;
+			2) mv "$dir-1" "$dir-2" ;;
+			3) rmdir "$dir-2" ;;
+		esac
+
+		if [ $? != 0 ]; then
+			t_fail "${op_mnt[*]} failed at op $op"
+		fi
+	done
+
+	# advance through mnt nrs for each op
+	i=0
+	while [ ${op_mnt[$NR_OPS]} == 0 ]; do
+		((op_mnt[$i]++))
+		if [ ${op_mnt[$i]} -ge $NR_MNTS ]; then
+			op_mnt[$i]=0
+			((i++))
+		else
+			break
+		fi
+	done
+done
+
+t_pass