From mboxrd@z Thu Jan 1 00:00:00 1970 From: NeilBrown Subject: [md PATCH 14/28] md: add support for raid5 to raid4 conversion Date: Thu, 15 Apr 2010 16:21:08 +1000 Message-ID: <20100415062108.5126.80043.stgit@notabene.brown> References: <20100415061516.5126.53068.stgit@notabene.brown> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20100415061516.5126.53068.stgit@notabene.brown> Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org List-Id: linux-raid.ids This is unlikely to be wanted, but we may as well provide it for completeness. Signed-off-by: NeilBrown --- drivers/md/raid5.c | 13 +++++++++++++ 1 files changed, 13 insertions(+), 0 deletions(-) diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index bb28fd6..020143d 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -5788,6 +5788,18 @@ static void *raid5_takeover(mddev_t *mddev) return ERR_PTR(-EINVAL); } +static void *raid4_takeover(mddev_t *mddev) +{ + /* raid4 can take over raid5 if layout is right. + */ + if (mddev->level == 5 && + mddev->layout == ALGORITHM_PARITY_N) { + mddev->new_layout = 0; + mddev->new_level = 4; + return setup_conf(mddev); + } + return ERR_PTR(-EINVAL); +} static struct mdk_personality raid5_personality; @@ -5903,6 +5915,7 @@ static struct mdk_personality raid4_personality = .start_reshape = raid5_start_reshape, .finish_reshape = raid5_finish_reshape, .quiesce = raid5_quiesce, + .takeover = raid4_takeover, }; static int __init raid5_init(void)