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RCVD_COUNT_TWO(0.00)[2]; TO_MATCH_ENVRCPT_ALL(0.00)[]; DKIM_TRACE(0.00)[suse.de:+] X-Rspamd-Queue-Id: 3849321ED7 X-Spam-Flag: NO X-Spam-Score: -3.31 X-Spam-Level: On 5/24/25 08:13, Yu Kuai wrote: > From: Yu Kuai > > Currently bitmap_ops is registered while allocating mddev, this is fine > when there is only one bitmap_ops, however, after introduing a new > bitmap_ops, user space need a time window to choose which bitmap_ops to > use while creating new array. > > Signed-off-by: Yu Kuai > --- > drivers/md/md.c | 86 +++++++++++++++++++++++++++++++------------------ > 1 file changed, 55 insertions(+), 31 deletions(-) > > diff --git a/drivers/md/md.c b/drivers/md/md.c > index 4eb0c6effd5b..dc4b85f30e13 100644 > --- a/drivers/md/md.c > +++ b/drivers/md/md.c > @@ -674,39 +674,50 @@ static void no_op(struct percpu_ref *r) {} > > static bool mddev_set_bitmap_ops(struct mddev *mddev) > { > + struct bitmap_operations *old = mddev->bitmap_ops; > + struct md_submodule_head *head; > + > + if (mddev->bitmap_id == ID_BITMAP_NONE || > + (old && old->head.id == mddev->bitmap_id)) > + return true; > + > xa_lock(&md_submodule); > - mddev->bitmap_ops = xa_load(&md_submodule, mddev->bitmap_id); > + head = xa_load(&md_submodule, mddev->bitmap_id); > xa_unlock(&md_submodule); > > - if (!mddev->bitmap_ops) { > - pr_warn_once("md: can't find bitmap id %d\n", mddev->bitmap_id); > + if (WARN_ON_ONCE(!head || head->type != MD_BITMAP)) { > + pr_err("md: can't find bitmap id %d\n", mddev->bitmap_id); > return false; > } > > + if (old && old->group) > + sysfs_remove_group(&mddev->kobj, old->group); > + > + mddev->bitmap_ops = (void *)head; > + if (mddev->bitmap_ops && mddev->bitmap_ops->group && > + sysfs_create_group(&mddev->kobj, mddev->bitmap_ops->group)) > + pr_warn("md: cannot register extra bitmap attributes for %s\n", > + mdname(mddev)); > + > return true; > } > > static void mddev_clear_bitmap_ops(struct mddev *mddev) > { > + if (mddev->bitmap_ops && mddev->bitmap_ops->group) > + sysfs_remove_group(&mddev->kobj, mddev->bitmap_ops->group); > + > mddev->bitmap_ops = NULL; > } > > int mddev_init(struct mddev *mddev) > { > - mddev->bitmap_id = ID_BITMAP; > - > - if (!mddev_set_bitmap_ops(mddev)) > - return -EINVAL; > - > if (percpu_ref_init(&mddev->active_io, active_io_release, > - PERCPU_REF_ALLOW_REINIT, GFP_KERNEL)) { > - mddev_clear_bitmap_ops(mddev); > + PERCPU_REF_ALLOW_REINIT, GFP_KERNEL)) > return -ENOMEM; > - } > > if (percpu_ref_init(&mddev->writes_pending, no_op, > PERCPU_REF_ALLOW_REINIT, GFP_KERNEL)) { > - mddev_clear_bitmap_ops(mddev); > percpu_ref_exit(&mddev->active_io); > return -ENOMEM; > } > @@ -734,6 +745,7 @@ int mddev_init(struct mddev *mddev) > mddev->resync_min = 0; > mddev->resync_max = MaxSector; > mddev->level = LEVEL_NONE; > + mddev->bitmap_id = ID_BITMAP; > > INIT_WORK(&mddev->sync_work, md_start_sync); > INIT_WORK(&mddev->del_work, mddev_delayed_delete); > @@ -744,7 +756,6 @@ EXPORT_SYMBOL_GPL(mddev_init); > > void mddev_destroy(struct mddev *mddev) > { > - mddev_clear_bitmap_ops(mddev); > percpu_ref_exit(&mddev->active_io); > percpu_ref_exit(&mddev->writes_pending); > } > @@ -6093,11 +6104,6 @@ struct mddev *md_alloc(dev_t dev, char *name) > return ERR_PTR(error); > } > > - if (md_bitmap_registered(mddev) && 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"); But now you've killed udev event processing. Once the 'add' event is sent _all_ sysfs attributes must be present, otherwise you'll have a race condition where udev is checking for attributes which are present only later. So when moving things around ensure to move the kobject_uevent() call, too. (ideally you would set the sysfs attributes when calling 'add_device()', but not sure if that's possible here.) Cheers, Hannes -- Dr. Hannes Reinecke Kernel Storage Architect hare@suse.de +49 911 74053 688 SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich