From nobody Mon Oct 6 13:38:24 2025 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 48A342E1C5B; Mon, 21 Jul 2025 17:17:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753118225; cv=none; b=kzZuN/nOPUn6xRc886nq7WPEFf+aY59+9CcUEYF569KSeEnbtqrxh8sJkt7cxfjkeaqp1hKcy47fI5g7DWXHIb21k6xYMRvLVD6GzR1df0SIdhiD+pm7/mNycYxQPXkjr57AsCGJL/40lsQYShlViPf1OEk4KCk+pUkVCRRMNwk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753118225; c=relaxed/simple; bh=5pgc4zXOdXGuNX2ZLbAwWqKRstkVZ5qA3HXDdsREGNM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=mD4DSAGXtycmjMP7wio9ZVoDCSYDCwMOIRsXQrUyqWfLP78FdG5I7mUIt4mTeewQoNzn8bvJMOpR8WwPcoZQ8avEeQcIAjt9VncCc92IihoV5c+0b7jXD8qRd3OSu5d5VnHy24HHCQrm4R9JBDAVSsOmytKBInzrFCQTfi+uLUI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=COmKAdqz; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="COmKAdqz" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C475AC4CEF6; Mon, 21 Jul 2025 17:17:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1753118225; bh=5pgc4zXOdXGuNX2ZLbAwWqKRstkVZ5qA3HXDdsREGNM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=COmKAdqzdbVEJjWfOYFrCG39bqVsXgcLAefSlZACWlzZoxbl/PF7TaqNZPwufpKWX dHIkJiVPqiLx62NtwxCT6Yx7LuYGYVEzDIPWnTnLrs9Y5vMrnNMJ8jy5RV0QT6VBm2 ubWXTL4Ylj8zpU9k+mBmSF3Ws5n37SGof5YPxroqUWLFfSTyoUrJ9VddjB24GuaIdN jPnFWaGt0BatovlRTMZxDIJgdqjjjkZOxYPfzyFuagDVbMx5Rd+QqvyMrw/SOS+SxO //fYq0AVzFd7fS1nxvzy20pDBO+hfjaExMekjoKxHhbYYKO3GLQzvUOcdqoQrP9zxV tsN2O6iY3xBTg== From: Yu Kuai To: corbet@lwn.net, agk@redhat.co, snitzer@kernel.org, mpatocka@redhat.com, hch@lst.de, song@kernel.org, hare@suse.de Cc: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, dm-devel@lists.linux.dev, linux-raid@vger.kernel.org, yukuai3@huawei.com, yangerkun@huawei.com, yi.zhang@huawei.com, johnny.chenyi@huawei.com Subject: [PATCH v4 06/11] md/md-bitmap: delay registration of bitmap_ops until creating bitmap Date: Tue, 22 Jul 2025 01:15:52 +0800 Message-ID: <20250721171557.34587-7-yukuai@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250721171557.34587-1-yukuai@kernel.org> References: <20250721171557.34587-1-yukuai@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Yu Kuai Currently bitmap_ops is registered while allocating mddev, this is fine when there is only one bitmap_ops. Delay setting bitmap_ops until creating bitmap, so that user can choose which bitmap to use before running the array. Signed-off-by: Yu Kuai --- Documentation/admin-guide/md.rst | 3 ++ drivers/md/md.c | 81 ++++++++++++++++++++------------ 2 files changed, 55 insertions(+), 29 deletions(-) diff --git a/Documentation/admin-guide/md.rst b/Documentation/admin-guide/m= d.rst index 356d2a344f08..001363f81850 100644 --- a/Documentation/admin-guide/md.rst +++ b/Documentation/admin-guide/md.rst @@ -388,6 +388,9 @@ All md devices contain: bitmap The default internal bitmap =20 +If bitmap_type is not none, then additional bitmap attributes bitmap/xxx or +llbitmap/xxx will be created after md device KOBJ_CHANGE event. + If bitmap_type is bitmap, then the md device will also contain: =20 bitmap/location diff --git a/drivers/md/md.c b/drivers/md/md.c index 41da352ccbde..744cac10506b 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -671,9 +671,11 @@ static void no_op(struct percpu_ref *r) {} =20 static bool mddev_set_bitmap_ops(struct mddev *mddev) { + struct bitmap_operations *old =3D mddev->bitmap_ops; struct md_submodule_head *head; =20 - if (mddev->bitmap_id =3D=3D ID_BITMAP_NONE) + if (mddev->bitmap_id =3D=3D ID_BITMAP_NONE || + (old && old->head.id =3D=3D mddev->bitmap_id)) return true; =20 xa_lock(&md_submodule); @@ -691,6 +693,18 @@ static bool mddev_set_bitmap_ops(struct mddev *mddev) =20 mddev->bitmap_ops =3D (void *)head; xa_unlock(&md_submodule); + + if (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)); + else + /* + * Inform user with KOBJ_CHANGE about new bitmap + * attributes. + */ + kobject_uevent(&mddev->kobj, KOBJ_CHANGE); + } return true; =20 err: @@ -700,28 +714,25 @@ static bool mddev_set_bitmap_ops(struct mddev *mddev) =20 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 =3D NULL; } =20 int mddev_init(struct mddev *mddev) { - if (!IS_ENABLED(CONFIG_MD_BITMAP)) { + if (!IS_ENABLED(CONFIG_MD_BITMAP)) mddev->bitmap_id =3D ID_BITMAP_NONE; - } else { + else mddev->bitmap_id =3D ID_BITMAP; - if (!mddev_set_bitmap_ops(mddev)) - return -EINVAL; - } =20 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; - } =20 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; } @@ -759,7 +770,6 @@ EXPORT_SYMBOL_GPL(mddev_init); =20 void mddev_destroy(struct mddev *mddev) { - mddev_clear_bitmap_ops(mddev); percpu_ref_exit(&mddev->active_io); percpu_ref_exit(&mddev->writes_pending); } @@ -6137,11 +6147,6 @@ struct mddev *md_alloc(dev_t dev, char *name) return ERR_PTR(error); } =20 - 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 =3D sysfs_get_dirent_safe(mddev->kobj.sd, "array_state= "); mddev->sysfs_level =3D sysfs_get_dirent_safe(mddev->kobj.sd, "level"); @@ -6217,6 +6222,26 @@ static void md_safemode_timeout(struct timer_list *t) =20 static int start_dirty_degraded; =20 +static int md_bitmap_create(struct mddev *mddev) +{ + if (mddev->bitmap_id =3D=3D ID_BITMAP_NONE) + return -EINVAL; + + if (!mddev_set_bitmap_ops(mddev)) + return -ENOENT; + + return mddev->bitmap_ops->create(mddev); +} + +static void md_bitmap_destroy(struct mddev *mddev) +{ + if (!md_bitmap_registered(mddev)) + return; + + mddev->bitmap_ops->destroy(mddev); + mddev_clear_bitmap_ops(mddev); +} + int md_run(struct mddev *mddev) { int err; @@ -6381,9 +6406,9 @@ int md_run(struct mddev *mddev) (unsigned long long)pers->size(mddev, 0, 0) / 2); err =3D -EINVAL; } - if (err =3D=3D 0 && pers->sync_request && md_bitmap_registered(mddev) && + if (err =3D=3D 0 && pers->sync_request && (mddev->bitmap_info.file || mddev->bitmap_info.offset)) { - err =3D mddev->bitmap_ops->create(mddev); + err =3D md_bitmap_create(mddev); if (err) pr_warn("%s: failed to create bitmap (%d)\n", mdname(mddev), err); @@ -6456,8 +6481,7 @@ int md_run(struct mddev *mddev) pers->free(mddev, mddev->private); mddev->private =3D NULL; put_pers(pers); - if (md_bitmap_registered(mddev)) - mddev->bitmap_ops->destroy(mddev); + md_bitmap_destroy(mddev); abort: bioset_exit(&mddev->io_clone_set); exit_sync_set: @@ -6480,7 +6504,7 @@ int do_md_run(struct mddev *mddev) if (md_bitmap_registered(mddev)) { err =3D mddev->bitmap_ops->load(mddev); if (err) { - mddev->bitmap_ops->destroy(mddev); + md_bitmap_destroy(mddev); goto out; } } @@ -6666,8 +6690,7 @@ static void __md_stop(struct mddev *mddev) { struct md_personality *pers =3D mddev->pers; =20 - if (md_bitmap_registered(mddev)) - mddev->bitmap_ops->destroy(mddev); + md_bitmap_destroy(mddev); mddev_detach(mddev); spin_lock(&mddev->lock); mddev->pers =3D NULL; @@ -7443,16 +7466,16 @@ static int set_bitmap_file(struct mddev *mddev, int= fd) err =3D 0; if (mddev->pers) { if (fd >=3D 0) { - err =3D mddev->bitmap_ops->create(mddev); + err =3D md_bitmap_create(mddev); if (!err) err =3D mddev->bitmap_ops->load(mddev); =20 if (err) { - mddev->bitmap_ops->destroy(mddev); + md_bitmap_destroy(mddev); fd =3D -1; } } else if (fd < 0) { - mddev->bitmap_ops->destroy(mddev); + md_bitmap_destroy(mddev); } } =20 @@ -7767,12 +7790,12 @@ static int update_array_info(struct mddev *mddev, m= du_array_info_t *info) mddev->bitmap_info.default_offset; mddev->bitmap_info.space =3D mddev->bitmap_info.default_space; - rv =3D mddev->bitmap_ops->create(mddev); + rv =3D md_bitmap_create(mddev); if (!rv) rv =3D mddev->bitmap_ops->load(mddev); =20 if (rv) - mddev->bitmap_ops->destroy(mddev); + md_bitmap_destroy(mddev); } else { struct md_bitmap_stats stats; =20 @@ -7798,7 +7821,7 @@ static int update_array_info(struct mddev *mddev, mdu= _array_info_t *info) put_cluster_ops(mddev); mddev->safemode_delay =3D DEFAULT_SAFEMODE_DELAY; } - mddev->bitmap_ops->destroy(mddev); + md_bitmap_destroy(mddev); mddev->bitmap_info.offset =3D 0; } } --=20 2.43.0