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Diffstat (limited to 'block/elevator.c')
-rw-r--r--block/elevator.c13
1 files changed, 12 insertions, 1 deletions
diff --git a/block/elevator.c b/block/elevator.c
index ebee948293e..bd78f693fcf 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -575,6 +575,9 @@ void elv_drain_elevator(struct request_queue *q)
*/
void elv_quiesce_start(struct request_queue *q)
{
+ if (!q->elevator)
+ return;
+
queue_flag_set(QUEUE_FLAG_ELVSWITCH, q);
/*
@@ -1050,6 +1053,9 @@ ssize_t elv_iosched_store(struct request_queue *q, const char *name,
char elevator_name[ELV_NAME_MAX];
struct elevator_type *e;
+ if (!q->elevator)
+ return count;
+
strlcpy(elevator_name, name, sizeof(elevator_name));
strstrip(elevator_name);
@@ -1073,10 +1079,15 @@ ssize_t elv_iosched_store(struct request_queue *q, const char *name,
ssize_t elv_iosched_show(struct request_queue *q, char *name)
{
struct elevator_queue *e = q->elevator;
- struct elevator_type *elv = e->elevator_type;
+ struct elevator_type *elv;
struct elevator_type *__e;
int len = 0;
+ if (!q->elevator)
+ return sprintf(name, "none\n");
+
+ elv = e->elevator_type;
+
spin_lock(&elv_list_lock);
list_for_each_entry(__e, &elv_list, list) {
if (!strcmp(elv->elevator_name, __e->elevator_name))