From patchwork Fri Apr 18 09:38:25 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu Kuai X-Patchwork-Id: 14057112 Received: from dggsgout12.his.huawei.com (dggsgout12.his.huawei.com [45.249.212.56]) (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 596EA204F6F; Fri, 18 Apr 2025 09:45:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.56 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744969540; cv=none; b=QPH3JD9lECSsQhABqVkiB5TWoaSNH5d/U1w2htC84s+JSRMQYSSrIODPAAYYtJohYdqBB0LXEB3mhPQyAz7RVLt8O2uLfEUMrBFt+vtAF3xfxRViBL08PcE1Q9OY7T7j+SMReA2QSehDy0uRE33XvySl3r4KF4C+Rj3mYZ6zw50= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744969540; c=relaxed/simple; bh=4zPHwMiowHy/kThRUPCqNfHIPBFyzhAe1GkacMCd7FA=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=XogboFBS5R4lmltOywfDwAVxv9NriyvQ3bm2LWhUl1T7HR24qUeLeaZUBBG9ZXfudb7TYuyJ0R72WSOwO50znu5qylB2zdKEk65wgaadj2qfEd80gpegS4jQwczEJlQVNO95by4Yxr+EzVGHpdJ8UIAQLmmSy7khDOrwiS5Q/v8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.163.216]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4Zf8xy6ySsz4f3jHh; Fri, 18 Apr 2025 17:45:10 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.128]) by mail.maildlp.com (Postfix) with ESMTP id BA1561A1B91; Fri, 18 Apr 2025 17:45:34 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.104.67]) by APP4 (Coremail) with SMTP id gCh0CgBHrGA6HwJozQ1aJw--.29179S8; Fri, 18 Apr 2025 17:45:34 +0800 (CST) From: Yu Kuai To: axboe@kernel.dk, kbusch@kernel.org Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, yukuai3@huawei.com, yukuai1@huaweicloud.com, yi.zhang@huawei.com, yangerkun@huawei.com, johnny.chenyi@huawei.com Subject: [PATCH 4/5] brd: fix discard end sector Date: Fri, 18 Apr 2025 17:38:25 +0800 Message-Id: <20250418093826.3149293-5-yukuai1@huaweicloud.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20250418093826.3149293-1-yukuai1@huaweicloud.com> References: <20250418093826.3149293-1-yukuai1@huaweicloud.com> Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: gCh0CgBHrGA6HwJozQ1aJw--.29179S8 X-Coremail-Antispam: 1UD129KBjvJXoW7Cw1rCrWxuFW7Kr4UGw15Arb_yoW8Xw1rpF 4UJFZ29ry5Cr1UK3WYq3s8uryFqayxGa4fKay7u3yYkw4fGF9Fka97t34rXay8GrWfury3 A3Z3t34rZrykA3DanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUPj14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_JF0E3s1l82xGYI kIc2x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2 z4x0Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F 4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq 3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7 IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4U M4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwCY1x0262kKe7AKxVWUtV W8ZwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v2 6r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIxkGc2 Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_ Gr0_Cr1lIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r4j6F4UMI IF0xvEx4A2jsIEc7CjxVAFwI0_Gr1j6F4UJbIYCTnIWIevJa73UjIFyTuYvjfUOyIUUUUU U X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ From: Yu Kuai brd_do_discard() just aligned start sector to page, this can only work if the discard size if at least one page. For example: blkdiscard /dev/ram0 -o 5120 -l 1024 In this case, size = (1024 - (8192 - 5120)), which is a huge value. Fix the problem by round_down() the end sector. Fixes: 9ead7efc6f3f ("brd: implement discard support") Signed-off-by: Yu Kuai --- drivers/block/brd.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/block/brd.c b/drivers/block/brd.c index 21e841e09a89..bf1e1b2a0d28 100644 --- a/drivers/block/brd.c +++ b/drivers/block/brd.c @@ -234,18 +234,21 @@ static void brd_free_one_page(struct rcu_head *head) static void brd_do_discard(struct brd_device *brd, sector_t sector, u32 size) { sector_t aligned_sector = round_up(sector, PAGE_SECTORS); + sector_t aligned_end = round_down(sector + (size >> SECTOR_SHIFT), + PAGE_SECTORS); struct page *page; - size -= (aligned_sector - sector) * SECTOR_SIZE; + if (aligned_end <= aligned_sector) + return; + xa_lock(&brd->brd_pages); - while (size >= PAGE_SIZE && aligned_sector < rd_size * 2) { + while (aligned_sector < aligned_end && aligned_sector < rd_size * 2) { page = __xa_erase(&brd->brd_pages, aligned_sector >> PAGE_SECTORS_SHIFT); if (page) { call_rcu(&page->rcu_head, brd_free_one_page); brd->brd_nr_pages--; } aligned_sector += PAGE_SECTORS; - size -= PAGE_SIZE; } xa_unlock(&brd->brd_pages); }