1 files changed, 82 insertions, 0 deletions
diff --git a/include/linux/part_stat.h b/include/linux/part_stat.h
new file mode 100644
index 000000000000..abeba356bc3f
--- /dev/null
+++ b/include/linux/part_stat.h
@@ -0,0 +1,82 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_PART_STAT_H
+#define _LINUX_PART_STAT_H
+
+#include <linux/blkdev.h>
+#include <asm/local.h>
+
+struct disk_stats {
+	u64 nsecs[NR_STAT_GROUPS];
+	unsigned long sectors[NR_STAT_GROUPS];
+	unsigned long ios[NR_STAT_GROUPS];
+	unsigned long merges[NR_STAT_GROUPS];
+	unsigned long io_ticks;
+	local_t in_flight[2];
+};
+
+/*
+ * Macros to operate on percpu disk statistics:
+ *
+ * {disk|part|all}_stat_{add|sub|inc|dec}() modify the stat counters and should
+ * be called between disk_stat_lock() and disk_stat_unlock().
+ *
+ * part_stat_read() can be called at any time.
+ */
+#define part_stat_lock()	preempt_disable()
+#define part_stat_unlock()	preempt_enable()
+
+#define part_stat_get_cpu(part, field, cpu)				\
+	(per_cpu_ptr((part)->bd_stats, (cpu))->field)
+
+#define part_stat_get(part, field)					\
+	part_stat_get_cpu(part, field, smp_processor_id())
+
+#define part_stat_read(part, field)					\
+({									\
+	typeof((part)->bd_stats->field) res = 0;			\
+	unsigned int _cpu;						\
+	for_each_possible_cpu(_cpu)					\
+		res += per_cpu_ptr((part)->bd_stats, _cpu)->field; \
+	res;								\
+})
+
+static inline void part_stat_set_all(struct block_device *part, int value)
+{
+	int i;
+
+	for_each_possible_cpu(i)
+		memset(per_cpu_ptr(part->bd_stats, i), value,
+				sizeof(struct disk_stats));
+}
+
+#define part_stat_read_accum(part, field)				\
+	(part_stat_read(part, field[STAT_READ]) +			\
+	 part_stat_read(part, field[STAT_WRITE]) +			\
+	 part_stat_read(part, field[STAT_DISCARD]))
+
+#define __part_stat_add(part, field, addnd)				\
+	__this_cpu_add((part)->bd_stats->field, addnd)
+
+#define part_stat_add(part, field, addnd)	do {			\
+	__part_stat_add((part), field, addnd);				\
+	if ((part)->bd_partno)						\
+		__part_stat_add(bdev_whole(part), field, addnd);	\
+} while (0)
+
+#define part_stat_dec(part, field)					\
+	part_stat_add(part, field, -1)
+#define part_stat_inc(part, field)					\
+	part_stat_add(part, field, 1)
+#define part_stat_sub(part, field, subnd)				\
+	part_stat_add(part, field, -subnd)
+
+#define part_stat_local_dec(part, field)				\
+	local_dec(&(part_stat_get(part, field)))
+#define part_stat_local_inc(part, field)				\
+	local_inc(&(part_stat_get(part, field)))
+#define part_stat_local_read(part, field)				\
+	local_read(&(part_stat_get(part, field)))
+#define part_stat_local_read_cpu(part, field, cpu)			\
+	local_read(&(part_stat_get_cpu(part, field, cpu)))
+
+#endif /* _LINUX_PART_STAT_H */