From mboxrd@z Thu Jan 1 00:00:00 1970 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 E8C8A2C21C5; Sun, 19 Apr 2026 03:10:25 +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=1776568225; cv=none; b=iqYXW9Nm51tjgxcnSqCKDRo2kRl+LzAAWkNm9dqKXE3olpn3zWH9FA4PUqQihg4wrMCe1ujcvMP/e+el4t7ynRLagughUh0UUQlGh/3Dj13f6Rl/W4es9NOB9KFsrpb25apATi2NY9SZGm74FVw2DQmFIvVtSe6Y7A9KZsScX2M= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776568225; c=relaxed/simple; bh=6q1TubjfN4xCCNBpN5ETCKBCMVavOt3aAJ4UfTTUzzs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JWs3SHtwMNWdtUAKy67WZoUL8t8TCvHSntaKxjXMsi10xAhMyy2uPFNX2L96u+TEN96/qOwKGEZAFJWTKXeQKOWSQdznAtsAc+mcoWBk0pqOUVEFPNHk6sZCA61u0Ztt9K/+2VuyGjYS/r70OFFvD6Oc+BzooJPthGO80nnt5AA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7BC8DC2BCB0; Sun, 19 Apr 2026 03:10:24 +0000 (UTC) From: Yu Kuai To: linux-raid@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Li Nan , Yu Kuai , Cheng Cheng Subject: [PATCH] md/raid5: add exact old and new llbitmap mapping helpers Date: Sun, 19 Apr 2026 11:09:39 +0800 Message-ID: <20260419030942.824195-17-yukuai@fnnas.com> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260419030942.824195-1-yukuai@fnnas.com> References: <20260419030942.824195-1-yukuai@fnnas.com> Precedence: bulk X-Mailing-List: linux-raid@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Teach RAID5 to export exact old and new llbitmap mappings and the corresponding sync and array sizes for reshape-aware bitmap users. Signed-off-by: Yu Kuai --- drivers/md/raid5.c | 70 ++++++++++++++++++++++++++++++++++------------ 1 file changed, 52 insertions(+), 18 deletions(-) diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 1f8360d4cdb7..0c58c175bad9 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -5898,25 +5898,43 @@ static enum reshape_loc get_reshape_loc(struct mddev *mddev, return LOC_BEHIND_RESHAPE; } -static void raid5_bitmap_sector(struct mddev *mddev, sector_t *offset, - unsigned long *sectors) +static void raid5_bitmap_sector_map(struct mddev *mddev, sector_t *offset, + unsigned long *sectors, + bool previous) { struct r5conf *conf = mddev->private; sector_t start = *offset; sector_t end = start + *sectors; - sector_t prev_start = start; - sector_t prev_end = end; int sectors_per_chunk; - enum reshape_loc loc; int dd_idx; - sectors_per_chunk = conf->chunk_sectors * - (conf->raid_disks - conf->max_degraded); + if (previous) + sectors_per_chunk = conf->prev_chunk_sectors * + (conf->previous_raid_disks - conf->max_degraded); + else + sectors_per_chunk = conf->chunk_sectors * + (conf->raid_disks - conf->max_degraded); start = round_down(start, sectors_per_chunk); end = round_up(end, sectors_per_chunk); - start = raid5_compute_sector(conf, start, 0, &dd_idx, NULL); - end = raid5_compute_sector(conf, end, 0, &dd_idx, NULL); + start = raid5_compute_sector(conf, start, previous, &dd_idx, NULL); + end = raid5_compute_sector(conf, end, previous, &dd_idx, NULL); + *offset = start; + *sectors = end - start; +} + +static void raid5_bitmap_sector(struct mddev *mddev, sector_t *offset, + unsigned long *sectors) +{ + struct r5conf *conf = mddev->private; + sector_t start = *offset; + sector_t end = start + *sectors; + sector_t prev_start = start; + unsigned long prev_sectors = end - start; + enum reshape_loc loc; + + raid5_bitmap_sector_map(mddev, &start, sectors, false); + end = start + *sectors; /* * For LOC_INSIDE_RESHAPE, this IO will wait for reshape to make @@ -5925,17 +5943,10 @@ static void raid5_bitmap_sector(struct mddev *mddev, sector_t *offset, loc = get_reshape_loc(mddev, conf, prev_start); if (likely(loc != LOC_AHEAD_OF_RESHAPE)) { *offset = start; - *sectors = end - start; return; } - sectors_per_chunk = conf->prev_chunk_sectors * - (conf->previous_raid_disks - conf->max_degraded); - prev_start = round_down(prev_start, sectors_per_chunk); - prev_end = round_down(prev_end, sectors_per_chunk); - - prev_start = raid5_compute_sector(conf, prev_start, 1, &dd_idx, NULL); - prev_end = raid5_compute_sector(conf, prev_end, 1, &dd_idx, NULL); + raid5_bitmap_sector_map(mddev, &prev_start, &prev_sectors, true); /* * for LOC_AHEAD_OF_RESHAPE, reshape can make progress before this IO @@ -5943,7 +5954,7 @@ static void raid5_bitmap_sector(struct mddev *mddev, sector_t *offset, * we set bits for both. */ *offset = min(start, prev_start); - *sectors = max(end, prev_end) - *offset; + *sectors = max(end, prev_start + prev_sectors) - *offset; } static enum stripe_result make_stripe_request(struct mddev *mddev, @@ -9002,6 +9013,20 @@ static void raid5_prepare_suspend(struct mddev *mddev) wake_up(&conf->wait_for_reshape); } +static sector_t raid5_bitmap_sync_size(struct mddev *mddev, bool previous) +{ + return mddev->dev_sectors; +} + +static sector_t raid5_bitmap_array_sectors(struct mddev *mddev, bool previous) +{ + struct r5conf *conf = mddev->private; + + if (previous) + return raid5_size(mddev, 0, 0); + return raid5_size(mddev, mddev->dev_sectors, conf->raid_disks); +} + static struct md_personality raid6_personality = { .head = { @@ -9031,6 +9056,9 @@ static struct md_personality raid6_personality = .change_consistency_policy = raid5_change_consistency_policy, .prepare_suspend = raid5_prepare_suspend, .bitmap_sector = raid5_bitmap_sector, + .bitmap_sector_map = raid5_bitmap_sector_map, + .bitmap_sync_size = raid5_bitmap_sync_size, + .bitmap_array_sectors = raid5_bitmap_array_sectors, }; static struct md_personality raid5_personality = { @@ -9061,6 +9089,9 @@ static struct md_personality raid5_personality = .change_consistency_policy = raid5_change_consistency_policy, .prepare_suspend = raid5_prepare_suspend, .bitmap_sector = raid5_bitmap_sector, + .bitmap_sector_map = raid5_bitmap_sector_map, + .bitmap_sync_size = raid5_bitmap_sync_size, + .bitmap_array_sectors = raid5_bitmap_array_sectors, }; static struct md_personality raid4_personality = @@ -9092,6 +9123,9 @@ static struct md_personality raid4_personality = .change_consistency_policy = raid5_change_consistency_policy, .prepare_suspend = raid5_prepare_suspend, .bitmap_sector = raid5_bitmap_sector, + .bitmap_sector_map = raid5_bitmap_sector_map, + .bitmap_sync_size = raid5_bitmap_sync_size, + .bitmap_array_sectors = raid5_bitmap_array_sectors, }; static int __init raid5_init(void) -- 2.51.0