From patchwork Tue Apr 12 12:30:15 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qu Wenruo X-Patchwork-Id: 560258 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D9F8DC433F5 for ; Tue, 12 Apr 2022 12:57:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243212AbiDLM7O (ORCPT ); Tue, 12 Apr 2022 08:59:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54058 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1354818AbiDLM4x (ORCPT ); Tue, 12 Apr 2022 08:56:53 -0400 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4D0424C789; Tue, 12 Apr 2022 05:30:43 -0700 (PDT) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 0DD261F858; Tue, 12 Apr 2022 12:30:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1649766642; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=n1inGQqZogERZHlidMkKbsMu1/LqTzn+vF1qdjBfslE=; b=dDZT+YzCeteQr2rZVvoxl7R0VrqFHfIYlCMeBiF33HE5BgqrbUQf1003XTAJgth4Tv/lS1 /Ihl01rMBKAwicvWp8LXhPSG9raJ6NIb6RgSISZBukvMU+oW6D69xjBwMOYe1ZZDMMuhb9 g5RjWUpXA4PrRKH1qE7ndMYE40GRYns= Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 0916913A99; Tue, 12 Apr 2022 12:30:40 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id kPgGL/BwVWKBewAAMHmgww (envelope-from ); Tue, 12 Apr 2022 12:30:40 +0000 From: Qu Wenruo To: linux-btrfs@vger.kernel.org Cc: stable@vger.kernel.org Subject: [PATCH v2 3/3] btrfs: return correct error number for __extent_writepage_io() Date: Tue, 12 Apr 2022 20:30:15 +0800 Message-Id: X-Mailer: git-send-email 2.35.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org [BUG] If we hit an error from submit_extent_page() inside __extent_writepage_io(), we could still return 0 to the caller, and even trigger the warning in btrfs_page_assert_not_dirty(). [CAUSE] In __extent_writepage_io(), if we hit an error from submit_extent_page(), we will just clean up the range and continue. This is completely fine for regular PAGE_SIZE == sectorsize, as we can only hit one sector in one page, thus after the error we're ensured to exit and @ret will be saved. But for subpage case, we may have other dirty subpage range in the page, and in the next loop, we may succeeded submitting the next range. In that case, @ret will be overwritten, and we return 0 to the caller, while we have hit some error. [FIX] Introduce @has_error and @saved_ret to record the first error we hit, so we will never forget what error we hit. CC: stable@vger.kernel.org # 5.15+ Signed-off-by: Qu Wenruo --- fs/btrfs/extent_io.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 990d8475ba31..df4e78ff3b18 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -3955,10 +3955,12 @@ static noinline_for_stack int __extent_writepage_io(struct btrfs_inode *inode, u64 extent_offset; u64 block_start; struct extent_map *em; + int saved_ret = 0; int ret = 0; int nr = 0; u32 opf = REQ_OP_WRITE; const unsigned int write_flags = wbc_to_write_flags(wbc); + bool has_error = false; bool compressed; ret = btrfs_writepage_cow_fixup(page); @@ -4008,6 +4010,9 @@ static noinline_for_stack int __extent_writepage_io(struct btrfs_inode *inode, if (IS_ERR(em)) { btrfs_page_set_error(fs_info, page, cur, end - cur + 1); ret = PTR_ERR_OR_ZERO(em); + has_error = true; + if (!saved_ret) + saved_ret = ret; break; } @@ -4071,6 +4076,10 @@ static noinline_for_stack int __extent_writepage_io(struct btrfs_inode *inode, end_bio_extent_writepage, 0, 0, false); if (ret) { + has_error = true; + if (!saved_ret) + saved_ret = ret; + btrfs_page_set_error(fs_info, page, cur, iosize); if (PageWriteback(page)) btrfs_page_clear_writeback(fs_info, page, cur, @@ -4084,8 +4093,10 @@ static noinline_for_stack int __extent_writepage_io(struct btrfs_inode *inode, * If we finish without problem, we should not only clear page dirty, * but also empty subpage dirty bits */ - if (!ret) + if (!has_error) btrfs_page_assert_not_dirty(fs_info, page); + else + ret = saved_ret; *nr_ret = nr; return ret; }