From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.cn.fujitsu.com ([183.91.158.132]:26117 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751527AbeAELR3 (ORCPT ); Fri, 5 Jan 2018 06:17:29 -0500 From: Gu Jinxiang To: CC: Qu Wenruo Subject: [v6 11/16] btrfs-progs: scrub: Introduce function to recover data parity Date: Fri, 5 Jan 2018 19:01:19 +0800 Message-ID: <1515150084-17231-12-git-send-email-gujx@cn.fujitsu.com> In-Reply-To: <1515150084-17231-1-git-send-email-gujx@cn.fujitsu.com> References: <1515150084-17231-1-git-send-email-gujx@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-btrfs-owner@vger.kernel.org List-ID: From: Qu Wenruo Introduce function, recover_from_parities(), to recover data stripes. It just wraps raid56_recov() with extra check functions to scrub_full_stripe structure. Signed-off-by: Qu Wenruo --- scrub.c | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) diff --git a/scrub.c b/scrub.c index 3db82656..d88c52e1 100644 --- a/scrub.c +++ b/scrub.c @@ -818,3 +818,54 @@ out: free(ptrs); return ret; } + +/* + * Try to recover data stripe from P or Q stripe + * + * Return >0 if it can't be require any more. + * Return 0 for successful repair or no need to repair at all + * Return <0 for fatal error + */ +static int recover_from_parities(struct btrfs_fs_info *fs_info, + struct btrfs_scrub_progress *scrub_ctx, + struct scrub_full_stripe *fstripe) +{ + void **ptrs; + int nr_stripes = fstripe->nr_stripes; + int stripe_len = BTRFS_STRIPE_LEN; + int max_tolerance; + int i; + int ret; + + /* No need to recover */ + if (!fstripe->nr_corrupted_stripes) + return 0; + + /* Already recovered once, no more chance */ + if (fstripe->recovered) + return 1; + + if (fstripe->bg_type & BTRFS_BLOCK_GROUP_RAID5) + max_tolerance = 1; + else + max_tolerance = 2; + + /* Out of repair */ + if (fstripe->nr_corrupted_stripes > max_tolerance) + return 1; + + ptrs = malloc(sizeof(void *) * fstripe->nr_stripes); + if (!ptrs) + return -ENOMEM; + + /* Construct ptrs */ + for (i = 0; i < nr_stripes; i++) + ptrs[i] = fstripe->stripes[i].data; + + ret = raid56_recov(nr_stripes, stripe_len, fstripe->bg_type, + fstripe->corrupted_index[0], + fstripe->corrupted_index[1], ptrs); + fstripe->recovered = 1; + free(ptrs); + return ret; +} -- 2.14.3