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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,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 A7F13C10F09 for ; Mon, 18 Feb 2019 05:28:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 78BFC218EA for ; Mon, 18 Feb 2019 05:28:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726500AbfBRF2H (ORCPT ); Mon, 18 Feb 2019 00:28:07 -0500 Received: from mx2.suse.de ([195.135.220.15]:55886 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726440AbfBRF2H (ORCPT ); Mon, 18 Feb 2019 00:28:07 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 6F54BAEF5 for ; Mon, 18 Feb 2019 05:28:06 +0000 (UTC) From: Qu Wenruo To: linux-btrfs@vger.kernel.org Subject: [PATCH v5.1 05/12] btrfs: extent_io: Handle error better in extent_write_full_page() Date: Mon, 18 Feb 2019 13:27:46 +0800 Message-Id: <20190218052753.24138-6-wqu@suse.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190218052753.24138-1-wqu@suse.com> References: <20190218052753.24138-1-wqu@suse.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org Since now flush_write_bio() could return error, kill the BUG_ON() first. Then don't call flush_write_bio() unconditionally, instead we check the return value from __extent_writepage() first. If __extent_writepage() fails, we do cleanup, and return error without submitting the possible corrupted or half-baked bio. If __extent_writepage() successes, then we call flush_write_bio() and return the result. Signed-off-by: Qu Wenruo --- fs/btrfs/extent_io.c | 24 +++++++++++++++++++++--- 1 file changed, 21 insertions(+), 3 deletions(-) diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 47a579650a61..d14c11592495 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -169,6 +169,16 @@ static int __must_check submit_one_bio(struct bio *bio, int mirror_num, return blk_status_to_errno(ret); } +/* A wrapper for bio_endio() to cleanup unsubmitted bios */ +static void end_write_bio(struct extent_page_data *epd, int ret) +{ + if (epd->bio) { + epd->bio->bi_status = errno_to_blk_status(ret); + bio_endio(epd->bio); + epd->bio = NULL; + } +} + /* * A wrapper for submit_one_bio(). * @@ -3431,6 +3441,9 @@ static noinline_for_stack int __extent_writepage_io(struct inode *inode, * records are inserted to lock ranges in the tree, and as dirty areas * are found, they are marked writeback. Then the lock bits are removed * and the end_io handler clears the writeback ranges + * + * Return 0 if everything goes well. + * Return <0 for error. */ static int __extent_writepage(struct page *page, struct writeback_control *wbc, struct extent_page_data *epd) @@ -3500,6 +3513,7 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc, end_extent_writepage(page, ret, start, page_end); } unlock_page(page); + ASSERT(ret <= 0); return ret; done_unlocked: @@ -4040,7 +4054,6 @@ static int extent_write_cache_pages(struct address_space *mapping, int extent_write_full_page(struct page *page, struct writeback_control *wbc) { int ret; - int flush_ret; struct extent_page_data epd = { .bio = NULL, .tree = &BTRFS_I(page->mapping->host)->io_tree, @@ -4049,9 +4062,14 @@ int extent_write_full_page(struct page *page, struct writeback_control *wbc) }; ret = __extent_writepage(page, wbc, &epd); + ASSERT(ret <= 0); + if (ret < 0) { + end_write_bio(&epd, ret); + return ret; + } - flush_ret = flush_write_bio(&epd); - BUG_ON(flush_ret < 0); + ret = flush_write_bio(&epd); + ASSERT(ret <= 0); return ret; } -- 2.20.1