kobject: kset_uevent_ops: make uevent() callback take a const *

The uevent() callback in struct kset_uevent_ops does not modify the
kobject passed into it, so make the pointer const to enforce this
restriction. When doing so, fix up all existing uevent() callbacks to
have the correct signature to preserve the build.

Cc: Christine Caulfield <[e-mail]>
Cc: David Teigland <[e-mail]>
Cc: Bob Peterson <[e-mail]>
Cc: Andreas Gruenbacher <[e-mail]>
Acked-by: Rafael J. Wysocki <[e-mail]>
Acked-by: Hans de Goede <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/base/core.c

···
 	return NULL;
 }
 
-static int dev_uevent(struct kobject *kobj, struct kobj_uevent_env *env)
+static int dev_uevent(const struct kobject *kobj, struct kobj_uevent_env *env)
 {
-	struct device *dev = kobj_to_dev(kobj);
+	const struct device *dev = kobj_to_dev(kobj);
 	int retval = 0;
 
 	/* add device node properties if present */

fs/dlm/lockspace.c

···
 	return ls->ls_uevent_result;
 }
 
-static int dlm_uevent(struct kobject *kobj, struct kobj_uevent_env *env)
+static int dlm_uevent(const struct kobject *kobj, struct kobj_uevent_env *env)
 {
-	struct dlm_ls *ls = container_of(kobj, struct dlm_ls, ls_kobj);
+	const struct dlm_ls *ls = container_of(kobj, struct dlm_ls, ls_kobj);
 
 	add_uevent_var(env, "LOCKSPACE=%s", ls->ls_name);
 	return 0;

fs/gfs2/sys.c

···
 	wait_for_completion(&sdp->sd_kobj_unregister);
 }
 
-static int gfs2_uevent(struct kobject *kobj, struct kobj_uevent_env *env)
+static int gfs2_uevent(const struct kobject *kobj, struct kobj_uevent_env *env)
 {
-	struct gfs2_sbd *sdp = container_of(kobj, struct gfs2_sbd, sd_kobj);
-	struct super_block *s = sdp->sd_vfs;
+	const struct gfs2_sbd *sdp = container_of(kobj, struct gfs2_sbd, sd_kobj);
+	const struct super_block *s = sdp->sd_vfs;
 
 	add_uevent_var(env, "LOCKTABLE=%s", sdp->sd_table_name);
 	add_uevent_var(env, "LOCKPROTO=%s", sdp->sd_proto_name);

include/linux/kobject.h

···
 struct kset_uevent_ops {
 	int (* const filter)(const struct kobject *kobj);
 	const char *(* const name)(const struct kobject *kobj);
-	int (* const uevent)(struct kobject *kobj, struct kobj_uevent_env *env);
+	int (* const uevent)(const struct kobject *kobj, struct kobj_uevent_env *env);
 };
 
 struct kobj_attribute {