[PATCH RFC 2/4] md/md-bitmap: merge md_bitmap_group into bitmap_operations

[Yu Kuai <yukuai1@xxxxxxxxxxxxxxx>]

From: Yu Kuai <yukuai3@xxxxxxxxxx>

Now that all bitmap implementations are internal, it doesn't make sense
to export md_bitmap_group anymore.

Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
---
 drivers/md/md-bitmap.c | 5 ++++-
 drivers/md/md-bitmap.h | 2 ++
 drivers/md/md.c        | 6 +++++-
 drivers/md/md.h        | 1 -
 4 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/md/md-bitmap.c b/drivers/md/md-bitmap.c
index c5e86f9b384f..f68eb79e739d 100644
--- a/drivers/md/md-bitmap.c
+++ b/drivers/md/md-bitmap.c
@@ -2963,7 +2963,8 @@ static struct attribute *md_bitmap_attrs[] = {
 	&max_backlog_used.attr,
 	NULL
 };
-const struct attribute_group md_bitmap_group = {
+
+static struct attribute_group md_bitmap_group = {
 	.name = "bitmap",
 	.attrs = md_bitmap_attrs,
 };
@@ -2996,6 +2997,8 @@ static struct bitmap_operations bitmap_ops = {
 	.copy_from_slot		= bitmap_copy_from_slot,
 	.set_pages		= bitmap_set_pages,
 	.free			= md_bitmap_free,
+
+	.group			= &md_bitmap_group,
 };
 
 void mddev_set_bitmap_ops(struct mddev *mddev)
diff --git a/drivers/md/md-bitmap.h b/drivers/md/md-bitmap.h
index 38425bf4a110..0c19983453c7 100644
--- a/drivers/md/md-bitmap.h
+++ b/drivers/md/md-bitmap.h
@@ -106,6 +106,8 @@ struct bitmap_operations {
 			      sector_t *hi, bool clear_bits);
 	void (*set_pages)(void *data, unsigned long pages);
 	void (*free)(void *data);
+
+	struct attribute_group *group;
 };
 
 /* the bitmap API */
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 35c2e1e761aa..aad9b87cafa0 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -5660,7 +5660,6 @@ static const struct attribute_group md_redundancy_group = {
 
 static const struct attribute_group *md_attr_groups[] = {
 	&md_default_group,
-	&md_bitmap_group,
 	NULL,
 };
 
@@ -5902,6 +5901,11 @@ struct mddev *md_alloc(dev_t dev, char *name)
 		return ERR_PTR(error);
 	}
 
+	if (mddev->bitmap_ops && mddev->bitmap_ops->group)
+		if (sysfs_create_group(&mddev->kobj, mddev->bitmap_ops->group))
+			pr_warn("md: cannot register extra bitmap attributes for %s\n",
+				mdname(mddev));
+
 	kobject_uevent(&mddev->kobj, KOBJ_ADD);
 	mddev->sysfs_state = sysfs_get_dirent_safe(mddev->kobj.sd, "array_state");
 	mddev->sysfs_level = sysfs_get_dirent_safe(mddev->kobj.sd, "level");
diff --git a/drivers/md/md.h b/drivers/md/md.h
index 4ba93af36126..a53af8818923 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -753,7 +753,6 @@ struct md_sysfs_entry {
 	ssize_t (*show)(struct mddev *, char *);
 	ssize_t (*store)(struct mddev *, const char *, size_t);
 };
-extern const struct attribute_group md_bitmap_group;
 
 static inline struct kernfs_node *sysfs_get_dirent_safe(struct kernfs_node *sd, char *name)
 {
-- 
2.39.2