block: move the part_stat* helpers from genhd.h to a new header

These macros are just used by a few files.  Move them out of genhd.h,
which is included everywhere into a new standalone header.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/blk.h

@@ -4,6 +4,7 @@
 
 #include <linux/idr.h>
 #include <linux/blk-mq.h>
+#include <linux/part_stat.h>
 #include <xen/xen.h>
 #include "blk-mq.h"
 #include "blk-mq-sched.h"

drivers/block/drbd/drbd_receiver.c

@@ -33,6 +33,7 @@
 #include <linux/random.h>
 #include <linux/string.h>
 #include <linux/scatterlist.h>
+#include <linux/part_stat.h>
 #include "drbd_int.h"
 #include "drbd_protocol.h"
 #include "drbd_req.h"

drivers/block/drbd/drbd_worker.c

@@ -22,6 +22,7 @@
 #include <linux/random.h>
 #include <linux/string.h>
 #include <linux/scatterlist.h>
+#include <linux/part_stat.h>
 
 #include "drbd_int.h"
 #include "drbd_protocol.h"

drivers/block/zram/zram_drv.c

@@ -33,6 +33,7 @@
 #include <linux/sysfs.h>
 #include <linux/debugfs.h>
 #include <linux/cpuhotplug.h>
+#include <linux/part_stat.h>
 
 #include "zram_drv.h"
 

drivers/md/dm.c

@@ -25,6 +25,7 @@
 #include <linux/wait.h>
 #include <linux/pr.h>
 #include <linux/refcount.h>
+#include <linux/part_stat.h>
 
 #define DM_MSG_PREFIX "core"
 

drivers/md/md.c

@@ -61,6 +61,7 @@
 #include <linux/raid/detect.h>
 #include <linux/slab.h>
 #include <linux/percpu-refcount.h>
+#include <linux/part_stat.h>
 
 #include <trace/events/block.h>
 #include "md.h"

drivers/nvme/target/admin-cmd.c

@@ -6,6 +6,7 @@
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 #include <linux/module.h>
 #include <linux/rculist.h>
+#include <linux/part_stat.h>
 
 #include <generated/utsrelease.h>
 #include <asm/unaligned.h>

fs/ext4/super.c

@@ -43,7 +43,7 @@
 #include <linux/uaccess.h>
 #include <linux/iversion.h>
 #include <linux/unicode.h>
-
+#include <linux/part_stat.h>
 #include <linux/kthread.h>
 #include <linux/freezer.h>
 

fs/ext4/sysfs.c

@@ -13,6 +13,7 @@
 #include <linux/seq_file.h>
 #include <linux/slab.h>
 #include <linux/proc_fs.h>
+#include <linux/part_stat.h>
 
 #include "ext4.h"
 #include "ext4_jbd2.h"

fs/f2fs/f2fs.h

@@ -22,6 +22,7 @@
 #include <linux/bio.h>
 #include <linux/blkdev.h>
 #include <linux/quotaops.h>
+#include <linux/part_stat.h>
 #include <crypto/hash.h>
 
 #include <linux/fscrypt.h>

fs/f2fs/super.c

@@ -24,6 +24,7 @@
 #include <linux/sysfs.h>
 #include <linux/quota.h>
 #include <linux/unicode.h>
+#include <linux/part_stat.h>
 
 #include "f2fs.h"
 #include "node.h"

include/linux/genhd.h

@@ -298,114 +298,6 @@ extern void disk_part_iter_init(struct disk_part_iter *piter,
 extern struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter);
 extern void disk_part_iter_exit(struct disk_part_iter *piter);
 
-/*
- * 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.
- *
- * part_stat_{add|set_all}() and {init|free}_part_stats are for
- * internal use only.
- */
-#ifdef	CONFIG_SMP
-#define part_stat_lock()	({ rcu_read_lock(); get_cpu(); })
-#define part_stat_unlock()	do { put_cpu(); rcu_read_unlock(); } while (0)
-
-#define part_stat_get_cpu(part, field, cpu)					\
-	(per_cpu_ptr((part)->dkstats, (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)->dkstats->field) res = 0;				\
-	unsigned int _cpu;						\
-	for_each_possible_cpu(_cpu)					\
-		res += per_cpu_ptr((part)->dkstats, _cpu)->field;	\
-	res;								\
-})
-
-static inline void part_stat_set_all(struct hd_struct *part, int value)
-{
-	int i;
-
-	for_each_possible_cpu(i)
-		memset(per_cpu_ptr(part->dkstats, i), value,
-				sizeof(struct disk_stats));
-}
-
-static inline int init_part_stats(struct hd_struct *part)
-{
-	part->dkstats = alloc_percpu(struct disk_stats);
-	if (!part->dkstats)
-		return 0;
-	return 1;
-}
-
-static inline void free_part_stats(struct hd_struct *part)
-{
-	free_percpu(part->dkstats);
-}
-
-#else /* !CONFIG_SMP */
-#define part_stat_lock()	({ rcu_read_lock(); 0; })
-#define part_stat_unlock()	rcu_read_unlock()
-
-#define part_stat_get(part, field)		((part)->dkstats.field)
-#define part_stat_get_cpu(part, field, cpu)	part_stat_get(part, field)
-#define part_stat_read(part, field)		part_stat_get(part, field)
-
-static inline void part_stat_set_all(struct hd_struct *part, int value)
-{
-	memset(&part->dkstats, value, sizeof(struct disk_stats));
-}
-
-static inline int init_part_stats(struct hd_struct *part)
-{
-	return 1;
-}
-
-static inline void free_part_stats(struct hd_struct *part)
-{
-}
-
-#endif /* CONFIG_SMP */
-
-#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)				\
-	(part_stat_get(part, field) += (addnd))
-
-#define part_stat_add(part, field, addnd)	do {			\
-	__part_stat_add((part), field, addnd);				\
-	if ((part)->partno)						\
-		__part_stat_add(&part_to_disk((part))->part0,		\
-				field, addnd);				\
-} while (0)
-
-#define part_stat_dec(gendiskp, field)					\
-	part_stat_add(gendiskp, field, -1)
-#define part_stat_inc(gendiskp, field)					\
-	part_stat_add(gendiskp, field, 1)
-#define part_stat_sub(gendiskp, field, subnd)				\
-	part_stat_add(gendiskp, field, -subnd)
-
-#define part_stat_local_dec(gendiskp, field)				\
-	local_dec(&(part_stat_get(gendiskp, field)))
-#define part_stat_local_inc(gendiskp, field)				\
-	local_inc(&(part_stat_get(gendiskp, field)))
-#define part_stat_local_read(gendiskp, field)				\
-	local_read(&(part_stat_get(gendiskp, field)))
-#define part_stat_local_read_cpu(gendiskp, field, cpu)			\
-	local_read(&(part_stat_get_cpu(gendiskp, field, cpu)))
-
 /* block/genhd.c */
 extern void device_add_disk(struct device *parent, struct gendisk *disk,
 			    const struct attribute_group **groups);

include/linux/part_stat.h

@@ -0,0 +1,115 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_PART_STAT_H
+#define _LINUX_PART_STAT_H
+
+#include <linux/genhd.h>
+
+/*
+ * 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.
+ *
+ * part_stat_{add|set_all}() and {init|free}_part_stats are for
+ * internal use only.
+ */
+#ifdef	CONFIG_SMP
+#define part_stat_lock()	({ rcu_read_lock(); get_cpu(); })
+#define part_stat_unlock()	do { put_cpu(); rcu_read_unlock(); } while (0)
+
+#define part_stat_get_cpu(part, field, cpu)				\
+	(per_cpu_ptr((part)->dkstats, (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)->dkstats->field) res = 0;				\
+	unsigned int _cpu;						\
+	for_each_possible_cpu(_cpu)					\
+		res += per_cpu_ptr((part)->dkstats, _cpu)->field;	\
+	res;								\
+})
+
+static inline void part_stat_set_all(struct hd_struct *part, int value)
+{
+	int i;
+
+	for_each_possible_cpu(i)
+		memset(per_cpu_ptr(part->dkstats, i), value,
+				sizeof(struct disk_stats));
+}
+
+static inline int init_part_stats(struct hd_struct *part)
+{
+	part->dkstats = alloc_percpu(struct disk_stats);
+	if (!part->dkstats)
+		return 0;
+	return 1;
+}
+
+static inline void free_part_stats(struct hd_struct *part)
+{
+	free_percpu(part->dkstats);
+}
+
+#else /* !CONFIG_SMP */
+#define part_stat_lock()	({ rcu_read_lock(); 0; })
+#define part_stat_unlock()	rcu_read_unlock()
+
+#define part_stat_get(part, field)		((part)->dkstats.field)
+#define part_stat_get_cpu(part, field, cpu)	part_stat_get(part, field)
+#define part_stat_read(part, field)		part_stat_get(part, field)
+
+static inline void part_stat_set_all(struct hd_struct *part, int value)
+{
+	memset(&part->dkstats, value, sizeof(struct disk_stats));
+}
+
+static inline int init_part_stats(struct hd_struct *part)
+{
+	return 1;
+}
+
+static inline void free_part_stats(struct hd_struct *part)
+{
+}
+
+#endif /* CONFIG_SMP */
+
+#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)				\
+	(part_stat_get(part, field) += (addnd))
+
+#define part_stat_add(part, field, addnd)	do {			\
+	__part_stat_add((part), field, addnd);				\
+	if ((part)->partno)						\
+		__part_stat_add(&part_to_disk((part))->part0,		\
+				field, addnd);				\
+} while (0)
+
+#define part_stat_dec(gendiskp, field)					\
+	part_stat_add(gendiskp, field, -1)
+#define part_stat_inc(gendiskp, field)					\
+	part_stat_add(gendiskp, field, 1)
+#define part_stat_sub(gendiskp, field, subnd)				\
+	part_stat_add(gendiskp, field, -subnd)
+
+#define part_stat_local_dec(gendiskp, field)				\
+	local_dec(&(part_stat_get(gendiskp, field)))
+#define part_stat_local_inc(gendiskp, field)				\
+	local_inc(&(part_stat_get(gendiskp, field)))
+#define part_stat_local_read(gendiskp, field)				\
+	local_read(&(part_stat_get(gendiskp, field)))
+#define part_stat_local_read_cpu(gendiskp, field, cpu)			\
+	local_read(&(part_stat_get_cpu(gendiskp, field, cpu)))
+
+#endif /* _LINUX_PART_STAT_H */