From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 26952C433DB for ; Sat, 16 Jan 2021 07:17:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D9C3B23AC6 for ; Sat, 16 Jan 2021 07:17:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726831AbhAPHRe (ORCPT ); Sat, 16 Jan 2021 02:17:34 -0500 Received: from mx2.suse.de ([195.135.220.15]:56144 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726774AbhAPHRe (ORCPT ); Sat, 16 Jan 2021 02:17:34 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1610781383; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=9vs/i6yNyAbx7v+kPD+/+rY6/TnnwFabTg4YyoXv5RU=; b=tvtCKtYitoT/ijn1OAA3cXf6cPZhWKhT/gMwHYwrMo5iOx8GPe4FEcoWjgfqaxdHyUrnVC o+U3+Lyi6owLVVCtRLRdHSPQNabYIG7J/SsrBDNAU3J7giTK6PZnQ9QAaikJKTw36t/NeG O9PywXEFl2DhgvcMFSaS+vp0Tvg7nbE= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id ED5EEB907 for ; Sat, 16 Jan 2021 07:16:22 +0000 (UTC) From: Qu Wenruo To: linux-btrfs@vger.kernel.org Subject: [PATCH v4 15/18] btrfs: disk-io: introduce subpage metadata validation check Date: Sat, 16 Jan 2021 15:15:30 +0800 Message-Id: <20210116071533.105780-16-wqu@suse.com> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210116071533.105780-1-wqu@suse.com> References: <20210116071533.105780-1-wqu@suse.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org For subpage metadata validation check, there are some difference: - Read must finish in one bvec Since we're just reading one subpage range in one page, it should never be split into two bios nor two bvecs. - How to grab the existing eb Instead of grabbing eb using page->private, we have to go search radix tree as we don't have any direct pointer at hand. Signed-off-by: Qu Wenruo --- fs/btrfs/disk-io.c | 57 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 5473bed6a7e8..7d2875c18958 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -591,6 +591,59 @@ static int validate_extent_buffer(struct extent_buffer *eb) return ret; } +static int validate_subpage_buffer(struct page *page, u64 start, u64 end, + int mirror) +{ + struct btrfs_fs_info *fs_info = btrfs_sb(page->mapping->host->i_sb); + struct extent_buffer *eb; + int reads_done; + int ret = 0; + + /* + * We don't allow bio merge for subpage metadata read, so we should + * only get one eb for each endio hook. + */ + ASSERT(end == start + fs_info->nodesize - 1); + ASSERT(PagePrivate(page)); + + eb = find_extent_buffer(fs_info, start); + /* + * When we are reading one tree block, eb must have been + * inserted into the radix tree. If not something is wrong. + */ + ASSERT(eb); + + reads_done = atomic_dec_and_test(&eb->io_pages); + /* Subpage read must finish in page read */ + ASSERT(reads_done); + + eb->read_mirror = mirror; + if (test_bit(EXTENT_BUFFER_READ_ERR, &eb->bflags)) { + ret = -EIO; + goto err; + } + ret = validate_extent_buffer(eb); + if (ret < 0) + goto err; + + if (test_and_clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags)) + btree_readahead_hook(eb, ret); + + set_extent_buffer_uptodate(eb); + + free_extent_buffer(eb); + return ret; +err: + /* + * end_bio_extent_readpage decrements io_pages in case of error, + * make sure it has something to decrement. + */ + atomic_inc(&eb->io_pages); + clear_extent_buffer_uptodate(eb); + free_extent_buffer(eb); + return ret; +} + int btrfs_validate_metadata_buffer(struct btrfs_io_bio *io_bio, struct page *page, u64 start, u64 end, int mirror) @@ -600,6 +653,10 @@ int btrfs_validate_metadata_buffer(struct btrfs_io_bio *io_bio, int reads_done; ASSERT(page->private); + + if (btrfs_sb(page->mapping->host->i_sb)->sectorsize < PAGE_SIZE) + return validate_subpage_buffer(page, start, end, mirror); + eb = (struct extent_buffer *)page->private; /* -- 2.30.0