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 AA8802848A1; Sun, 19 Apr 2026 03:10:12 +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=1776568212; cv=none; b=M8BECC2VsznadCL/LUafAjQZMYX8rwYsRLJASwzEo3x/11Il0w3XDqT8VLR5uBZG35Vqvog440NmQ2GR1WBw6VlNXk9wXOzPJ0BAor/Ufsi1OaZZgz20HRtHbl5R55o3R607Y115fxImjIRqIphtM+SSVCKjbcMlLcbS7FRGVp0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776568212; c=relaxed/simple; bh=eFZtbZyKATU7rxviH+w6yWaIugUGFX8rBUHfrCpmhkY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=cixw779Uv6Ee+Z6s07VeeBxe35XJmkYDR2hFGDnLmhBH+xBrGaVqQ+1KZDteXxRqgsbV2uuo42355Kqur3c+YbI0UsC+zQsbr0gZQu7P8KGOIGxJEs2XS+hGv1x7C3xXsgziPnnWuZEj9TNIwItdPM3kOygiSjsHl8TyqosAVn8= 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 09657C2BCB0; Sun, 19 Apr 2026 03:10:10 +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/md-llbitmap: add reshape range mapping helpers Date: Sun, 19 Apr 2026 11:09:32 +0800 Message-ID: <20260419030942.824195-10-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 llbitmap to choose old versus new geometry during reshape and to encode exact bitmap ranges for the active geometry. This is the mapping groundwork for checkpoint remapping. Signed-off-by: Yu Kuai --- drivers/md/md-llbitmap.c | 96 ++++++++++++++++++++++++++++++++++++++-- 1 file changed, 92 insertions(+), 4 deletions(-) diff --git a/drivers/md/md-llbitmap.c b/drivers/md/md-llbitmap.c index 88169eeda4b5..fd1dc86afc69 100644 --- a/drivers/md/md-llbitmap.c +++ b/drivers/md/md-llbitmap.c @@ -9,6 +9,7 @@ #include #include #include +#include #include #include @@ -383,6 +384,16 @@ static sector_t llbitmap_personality_sync_size(struct llbitmap *llbitmap, return mddev->pers->bitmap_sync_size(mddev, previous); } +static sector_t llbitmap_logical_size(struct llbitmap *llbitmap, bool previous) +{ + struct mddev *mddev = llbitmap->mddev; + + if (!llbitmap_reshaping(llbitmap) || !mddev->private || !mddev->pers || + !mddev->pers->bitmap_array_sectors) + return llbitmap_personality_sync_size(llbitmap, previous); + return mddev->pers->bitmap_array_sectors(mddev, previous); +} + static void llbitmap_refresh_reshape(struct llbitmap *llbitmap) { unsigned long old_chunks = DIV_ROUND_UP_SECTOR_T(llbitmap->sync_size, @@ -399,6 +410,52 @@ static void llbitmap_refresh_reshape(struct llbitmap *llbitmap) llbitmap->chunks = max(old_chunks, llbitmap->reshape_chunks); } +static void llbitmap_map_layout(struct llbitmap *llbitmap, sector_t *offset, + unsigned long *sectors, bool previous) +{ + sector_t limit = llbitmap_logical_size(llbitmap, previous); + sector_t start = *offset; + sector_t end = start + *sectors; + + if (start >= limit) { + *sectors = 0; + return; + } + if (end > limit) + end = limit; + + *offset = start; + *sectors = end - start; + if (!*sectors) + return; + + if (llbitmap->mddev->pers->bitmap_sector_map) + llbitmap->mddev->pers->bitmap_sector_map(llbitmap->mddev, offset, + sectors, previous); + else if (!previous && llbitmap->mddev->pers->bitmap_sector) + llbitmap->mddev->pers->bitmap_sector(llbitmap->mddev, offset, + sectors); +} + +static void llbitmap_encode_range(struct llbitmap *llbitmap, sector_t *offset, + unsigned long *sectors, bool previous) +{ + unsigned long chunksize = previous ? llbitmap->chunksize : + llbitmap->reshape_chunksize; + u64 start; + u64 end; + + if (!*sectors) { + *offset = 0; + return; + } + + start = div64_u64(*offset, chunksize); + end = div64_u64(*offset + *sectors - 1, chunksize); + *offset = (sector_t)start << llbitmap->chunkshift; + *sectors = (end - start + 1) << llbitmap->chunkshift; +} + static enum llbitmap_state llbitmap_read(struct llbitmap *llbitmap, loff_t pos) { unsigned int idx; @@ -1248,11 +1305,32 @@ static void llbitmap_destroy(struct mddev *mddev) mutex_unlock(&mddev->bitmap_info.mutex); } +static bool llbitmap_map_previous(struct llbitmap *llbitmap, sector_t offset, + unsigned long sectors) +{ + struct mddev *mddev = llbitmap->mddev; + sector_t boundary = mddev->reshape_position; + + if (!llbitmap_reshaping(llbitmap)) + return false; + + WARN_ON_ONCE(sectors && offset < boundary && offset + sectors > boundary); + + return mddev->reshape_backwards ? offset < boundary : offset >= boundary; +} + static void llbitmap_prepare_range(struct mddev *mddev, sector_t *offset, unsigned long *sectors) { - if (mddev->pers->bitmap_sector) - mddev->pers->bitmap_sector(mddev, offset, sectors); + struct llbitmap *llbitmap = mddev->bitmap; + bool previous; + + if (!llbitmap) + return; + + previous = llbitmap_map_previous(llbitmap, *offset, *sectors); + llbitmap_map_layout(llbitmap, offset, sectors, previous); + llbitmap_encode_range(llbitmap, offset, sectors, previous); } static void llbitmap_start_write(struct mddev *mddev, sector_t offset, @@ -1421,7 +1499,11 @@ static bool llbitmap_blocks_synced(struct mddev *mddev, sector_t offset) { struct llbitmap *llbitmap = mddev->bitmap; unsigned long p = offset >> llbitmap->chunkshift; - enum llbitmap_state c = llbitmap_read(llbitmap, p); + enum llbitmap_state c; + + if (p >= llbitmap->chunks) + return false; + c = llbitmap_read(llbitmap, p); return c == BitClean || c == BitDirty; } @@ -1431,7 +1513,11 @@ static sector_t llbitmap_skip_sync_blocks(struct mddev *mddev, sector_t offset) struct llbitmap *llbitmap = mddev->bitmap; unsigned long p = offset >> llbitmap->chunkshift; int blocks = llbitmap->chunksize - (offset & (llbitmap->chunksize - 1)); - enum llbitmap_state c = llbitmap_read(llbitmap, p); + enum llbitmap_state c; + + if (p >= llbitmap->chunks) + return 0; + c = llbitmap_read(llbitmap, p); /* always skip unwritten blocks */ if (c == BitUnwritten) @@ -1461,6 +1547,8 @@ static bool llbitmap_start_sync(struct mddev *mddev, sector_t offset, * if md_do_sync() loop more times. */ *blocks = llbitmap->chunksize - (offset & (llbitmap->chunksize - 1)); + if (p >= llbitmap->chunks) + return false; return llbitmap_state_machine(llbitmap, p, p, BitmapActionStartsync) == BitSyncing; } -- 2.51.0