From patchwork Tue Nov 24 17:25:18 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Filipe Manana X-Patchwork-Id: 7698351 Return-Path: X-Original-To: patchwork-linux-btrfs@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 4DD06BF90C for ; Wed, 25 Nov 2015 11:59:17 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 6C5A6208F0 for ; Wed, 25 Nov 2015 11:59:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 621A6208ED for ; Wed, 25 Nov 2015 11:59:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751579AbbKYL7M (ORCPT ); Wed, 25 Nov 2015 06:59:12 -0500 Received: from mail.kernel.org ([198.145.29.136]:58148 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751320AbbKYL7L (ORCPT ); Wed, 25 Nov 2015 06:59:11 -0500 Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id F4091208F0; Wed, 25 Nov 2015 11:59:09 +0000 (UTC) Received: from debian3.lan (bl8-199-62.dsl.telepac.pt [85.241.199.62]) (using TLSv1.2 with cipher AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9DD73208ED; Wed, 25 Nov 2015 11:59:08 +0000 (UTC) From: fdmanana@kernel.org To: linux-btrfs@vger.kernel.org Cc: Filipe Manana Subject: [PATCH] Btrfs: fix error path when failing to submit bio for direct IO write Date: Tue, 24 Nov 2015 17:25:18 +0000 Message-Id: <1448385918-5536-1-git-send-email-fdmanana@kernel.org> X-Mailer: git-send-email 2.1.3 X-Spam-Status: No, score=-6.4 required=5.0 tests=BAYES_00, DATE_IN_PAST_12_24, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Filipe Manana Commit 61de718fceb6 ("Btrfs: fix memory corruption on failure to submit bio for direct IO") fixed problems with the error handling code after we fail to submit a bio for direct IO. However there were 2 problems that it did not address when the failure is due to memory allocation failures for direct IO writes: 1) We considered that there could be only one ordered extent for the whole IO range, which is not always true, as we can have multiple; 2) It did not set the bit BTRFS_ORDERED_IO_DONE in the ordered extent, which can make other tasks running btrfs_wait_logged_extents() hang forever, since they wait for that bit to be set. The general assumption is that regardless of an error, the BTRFS_ORDERED_IO_DONE is always set and it precedes setting the bit BTRFS_ORDERED_COMPLETE. Fix these issues by moving part of the btrfs_endio_direct_write() handler into a new helper function and having that new helper function called when we fail to allocate memory to submit the bio (and its private object) for a direct IO write. Signed-off-by: Filipe Manana --- fs/btrfs/inode.c | 54 +++++++++++++++++++++++++++--------------------------- 1 file changed, 27 insertions(+), 27 deletions(-) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index f82d1f4..4f8560c 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -7995,22 +7995,22 @@ static void btrfs_endio_direct_read(struct bio *bio) bio_put(bio); } -static void btrfs_endio_direct_write(struct bio *bio) +static void btrfs_endio_direct_write_update_ordered(struct inode *inode, + const u64 offset, + const u64 bytes, + const int uptodate) { - struct btrfs_dio_private *dip = bio->bi_private; - struct inode *inode = dip->inode; struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_ordered_extent *ordered = NULL; - u64 ordered_offset = dip->logical_offset; - u64 ordered_bytes = dip->bytes; - struct bio *dio_bio; + u64 ordered_offset = offset; + u64 ordered_bytes = bytes; int ret; again: ret = btrfs_dec_test_first_ordered_pending(inode, &ordered, &ordered_offset, ordered_bytes, - !bio->bi_error); + uptodate); if (!ret) goto out_test; @@ -8023,13 +8023,22 @@ out_test: * our bio might span multiple ordered extents. If we haven't * completed the accounting for the whole dio, go back and try again */ - if (ordered_offset < dip->logical_offset + dip->bytes) { - ordered_bytes = dip->logical_offset + dip->bytes - - ordered_offset; + if (ordered_offset < offset + bytes) { + ordered_bytes = offset + bytes - ordered_offset; ordered = NULL; goto again; } - dio_bio = dip->dio_bio; +} + +static void btrfs_endio_direct_write(struct bio *bio) +{ + struct btrfs_dio_private *dip = bio->bi_private; + struct bio *dio_bio = dip->dio_bio; + + btrfs_endio_direct_write_update_ordered(dip->inode, + dip->logical_offset, + dip->bytes, + !bio->bi_error); kfree(dip); @@ -8365,24 +8374,15 @@ free_ordered: dip = NULL; io_bio = NULL; } else { - if (write) { - struct btrfs_ordered_extent *ordered; - - ordered = btrfs_lookup_ordered_extent(inode, - file_offset); - set_bit(BTRFS_ORDERED_IOERR, &ordered->flags); - /* - * Decrements our ref on the ordered extent and removes - * the ordered extent from the inode's ordered tree, - * doing all the proper resource cleanup such as for the - * reserved space and waking up any waiters for this - * ordered extent (through btrfs_remove_ordered_extent). - */ - btrfs_finish_ordered_io(ordered); - } else { + if (write) + btrfs_endio_direct_write_update_ordered(inode, + file_offset, + dio_bio->bi_iter.bi_size, + 1); + else unlock_extent(&BTRFS_I(inode)->io_tree, file_offset, file_offset + dio_bio->bi_iter.bi_size - 1); - } + dio_bio->bi_error = -EIO; /* * Releases and cleans up our dio_bio, no need to bio_put()