From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-181.mta0.migadu.com (out-181.mta0.migadu.com [91.218.175.181]) (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 056801DF98B for ; Sun, 4 May 2025 19:52:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.181 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746388336; cv=none; b=EXf0EYYcrsr27PYGpmqfcnCasvhEn5tnXRLQ2UHMd1jJ7olvS6XAKl5Ke3PHP9+Y0wHPWVTW1HcNb///ObQ+QArmTsu6/hcBt/sFYMpHea5PPh7Ur/iulNmdG2CbDp1Z1mkjs+4Lev0YLCiLMd3O93NKZDGykkPN6jUoovUfdS4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746388336; c=relaxed/simple; bh=/895FQEZorwGqq6iNyLyNRZv5w2vfn1omG7NTQJV80U=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=IwXcpU5gW7TzS32m/eX8BO3djwVKph68MGiJc2lus2vmFwMR8w2THVmndXJ+7tJrlWUeq71/O7JpLbreGzX3MNOpELxU/xNm6vo0FSGKo03IZVTIdCAk72C9ZEIYVDq5UZfj/jb6fpaBdvd4BYbPFpmh+7QZkIrLFQwo8rznSdU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=klC9jWHa; arc=none smtp.client-ip=91.218.175.181 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="klC9jWHa" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1746388331; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=lpWIlkpu6YCtARZsMlSNeAomJkcf/0xQNFgvarHbtEs=; b=klC9jWHa80vVBY+YYwNOEtlmNWbxsPAoGd24eWKrOudSXOjKrcfUJ0yZCLAHmkhd0W9d7k WfiIIwhMXMGNhcijKEgMCO+gYdNqQB+j68Gwlr+yeBcEKjqMKm6ahCkSsN8gURXJzBBiXd /vYEsvQQgjjSLBbu6yG83PMBeHAb/nk= From: Kent Overstreet To: linux-bcachefs@vger.kernel.org Cc: Kent Overstreet Subject: [PATCH 3/3] bcachefs: bcachefs_metadata_version_fast_device_removal Date: Sun, 4 May 2025 15:51:59 -0400 Message-ID: <20250504195202.2073437-4-kent.overstreet@linux.dev> In-Reply-To: <20250504195202.2073437-1-kent.overstreet@linux.dev> References: <20250504195202.2073437-1-kent.overstreet@linux.dev> Precedence: bulk X-Mailing-List: linux-bcachefs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT Fast device removal, that uses backpointers to find pointers to the device being removed instead of a full metadata scan. This requires BCH_SB_MEMBER_DELETED_UUID, which is an incompatible change - hence the version number bump. We don't fully trust backpointers, so we don't want to reuse device indexes until after a fsck has verified that there aren't any pointers to removed devices. Signed-off-by: Kent Overstreet --- fs/bcachefs/bcachefs_format.h | 3 ++- fs/bcachefs/super.c | 25 ++++++++++++++++++++++--- 2 files changed, 24 insertions(+), 4 deletions(-) diff --git a/fs/bcachefs/bcachefs_format.h b/fs/bcachefs/bcachefs_format.h index 0beff6af7ecf..baaf9786238b 100644 --- a/fs/bcachefs/bcachefs_format.h +++ b/fs/bcachefs/bcachefs_format.h @@ -696,7 +696,8 @@ struct bch_sb_field_ext { x(stripe_lru, BCH_VERSION(1, 23)) \ x(casefolding, BCH_VERSION(1, 24)) \ x(extent_flags, BCH_VERSION(1, 25)) \ - x(snapshot_deletion_v2, BCH_VERSION(1, 26)) + x(snapshot_deletion_v2, BCH_VERSION(1, 26)) \ + x(fast_device_removal, BCH_VERSION(1, 27)) enum bcachefs_metadata_version { bcachefs_metadata_version_min = 9, diff --git a/fs/bcachefs/super.c b/fs/bcachefs/super.c index 35b07410a8c6..18d8823cdb79 100644 --- a/fs/bcachefs/super.c +++ b/fs/bcachefs/super.c @@ -1719,6 +1719,8 @@ int bch2_dev_remove(struct bch_fs *c, struct bch_dev *ca, int flags) { struct bch_member *m; unsigned dev_idx = ca->dev_idx, data; + bool fast_device_removal = !bch2_request_incompat_feature(c, + bcachefs_metadata_version_fast_device_removal); int ret; down_write(&c->state_lock); @@ -1737,11 +1739,24 @@ int bch2_dev_remove(struct bch_fs *c, struct bch_dev *ca, int flags) __bch2_dev_read_only(c, ca); - ret = bch2_dev_data_drop(c, ca->dev_idx, flags); - bch_err_msg(ca, ret, "bch2_dev_data_drop()"); + ret = fast_device_removal + ? bch2_dev_data_drop_by_backpointers(c, ca->dev_idx, flags) + : bch2_dev_data_drop(c, ca->dev_idx, flags); if (ret) goto err; + /* Check if device still has data */ + struct bch_dev_usage usage = bch2_dev_usage_read(ca); + for (unsigned i = 0; i < BCH_DATA_NR; i++) + if (!data_type_is_empty(i) && + !data_type_is_hidden(i) && + usage.buckets[i]) { + bch_err(ca, "Remove failed: still has data (%s, %llu buckets)", + __bch2_data_types[i], usage.buckets[i]); + ret = -EBUSY; + goto err; + } + ret = bch2_dev_remove_alloc(c, ca); bch_err_msg(ca, ret, "bch2_dev_remove_alloc()"); if (ret) @@ -1805,7 +1820,11 @@ int bch2_dev_remove(struct bch_fs *c, struct bch_dev *ca, int flags) */ mutex_lock(&c->sb_lock); m = bch2_members_v2_get_mut(c->disk_sb.sb, dev_idx); - memset(&m->uuid, 0, sizeof(m->uuid)); + + if (fast_device_removal) + m->uuid = BCH_SB_MEMBER_DELETED_UUID; + else + memset(&m->uuid, 0, sizeof(m->uuid)); bch2_write_super(c); -- 2.49.0