block: add helpers for the trivial queue flag sysfs show/store entries

The code for nonrot, random, and io stats are completely identical.
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

block/blk-sysfs.c

@@ -180,26 +180,36 @@ static ssize_t queue_max_hw_sectors_show(struct request_queue *q, char *page)
 	return queue_var_show(max_hw_sectors_kb, (page));
 }
 
-static ssize_t queue_nonrot_show(struct request_queue *q, char *page)
-{
-	return queue_var_show(!blk_queue_nonrot(q), page);
-}
-
-static ssize_t queue_nonrot_store(struct request_queue *q, const char *page,
-				  size_t count)
-{
-	unsigned long nm;
-	ssize_t ret = queue_var_store(&nm, page, count);
-
-	spin_lock_irq(q->queue_lock);
-	if (nm)
-		queue_flag_clear(QUEUE_FLAG_NONROT, q);
-	else
-		queue_flag_set(QUEUE_FLAG_NONROT, q);
-	spin_unlock_irq(q->queue_lock);
-
-	return ret;
-}
+#define QUEUE_SYSFS_BIT_FNS(name, flag, neg)				\
+static ssize_t								\
+queue_show_##name(struct request_queue *q, char *page)			\
+{									\
+	int bit;							\
+	bit = test_bit(QUEUE_FLAG_##flag, &q->queue_flags);		\
+	return queue_var_show(neg ? !bit : bit, page);			\
+}									\
+static ssize_t								\
+queue_store_##name(struct request_queue *q, const char *page, size_t count) \
+{									\
+	unsigned long val;						\
+	ssize_t ret;							\
+	ret = queue_var_store(&val, page, count);			\
+	if (neg)							\
+		val = !val;						\
+									\
+	spin_lock_irq(q->queue_lock);					\
+	if (val)							\
+		queue_flag_set(QUEUE_FLAG_##flag, q);			\
+	else								\
+		queue_flag_clear(QUEUE_FLAG_##flag, q);			\
+	spin_unlock_irq(q->queue_lock);					\
+	return ret;							\
+}
+
+QUEUE_SYSFS_BIT_FNS(nonrot, NONROT, 1);
+QUEUE_SYSFS_BIT_FNS(random, ADD_RANDOM, 0);
+QUEUE_SYSFS_BIT_FNS(iostats, IO_STAT, 0);
+#undef QUEUE_SYSFS_BIT_FNS
 
 static ssize_t queue_nomerges_show(struct request_queue *q, char *page)
 {
@@ -250,48 +260,6 @@ queue_rq_affinity_store(struct request_queue *q, const char *page, size_t count)
 	return ret;
 }
 
-static ssize_t queue_random_show(struct request_queue *q, char *page)
-{
-	return queue_var_show(blk_queue_add_random(q), page);
-}
-
-static ssize_t queue_random_store(struct request_queue *q, const char *page,
-				  size_t count)
-{
-	unsigned long val;
-	ssize_t ret = queue_var_store(&val, page, count);
-
-	spin_lock_irq(q->queue_lock);
-	if (val)
-		queue_flag_set(QUEUE_FLAG_ADD_RANDOM, q);
-	else
-		queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, q);
-	spin_unlock_irq(q->queue_lock);
-
-	return ret;
-}
-
-static ssize_t queue_iostats_show(struct request_queue *q, char *page)
-{
-	return queue_var_show(blk_queue_io_stat(q), page);
-}
-
-static ssize_t queue_iostats_store(struct request_queue *q, const char *page,
-				   size_t count)
-{
-	unsigned long stats;
-	ssize_t ret = queue_var_store(&stats, page, count);
-
-	spin_lock_irq(q->queue_lock);
-	if (stats)
-		queue_flag_set(QUEUE_FLAG_IO_STAT, q);
-	else
-		queue_flag_clear(QUEUE_FLAG_IO_STAT, q);
-	spin_unlock_irq(q->queue_lock);
-
-	return ret;
-}
-
 static struct queue_sysfs_entry queue_requests_entry = {
 	.attr = {.name = "nr_requests", .mode = S_IRUGO | S_IWUSR },
 	.show = queue_requests_show,
@@ -373,8 +341,8 @@ static struct queue_sysfs_entry queue_discard_zeroes_data_entry = {
 
 static struct queue_sysfs_entry queue_nonrot_entry = {
 	.attr = {.name = "rotational", .mode = S_IRUGO | S_IWUSR },
-	.show = queue_nonrot_show,
-	.store = queue_nonrot_store,
+	.show = queue_show_nonrot,
+	.store = queue_store_nonrot,
 };
 
 static struct queue_sysfs_entry queue_nomerges_entry = {
@@ -391,14 +359,14 @@ static struct queue_sysfs_entry queue_rq_affinity_entry = {
 
 static struct queue_sysfs_entry queue_iostats_entry = {
 	.attr = {.name = "iostats", .mode = S_IRUGO | S_IWUSR },
-	.show = queue_iostats_show,
-	.store = queue_iostats_store,
+	.show = queue_show_iostats,
+	.store = queue_store_iostats,
 };
 
 static struct queue_sysfs_entry queue_random_entry = {
 	.attr = {.name = "add_random", .mode = S_IRUGO | S_IWUSR },
-	.show = queue_random_show,
-	.store = queue_random_store,
+	.show = queue_show_random,
+	.store = queue_store_random,
 };
 
 static struct attribute *default_attrs[] = {