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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 1EB21C43381 for ; Thu, 28 Jan 2021 18:28:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E303F64E21 for ; Thu, 28 Jan 2021 18:27:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229722AbhA1S1Q (ORCPT ); Thu, 28 Jan 2021 13:27:16 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:20045 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232072AbhA1SYm (ORCPT ); Thu, 28 Jan 2021 13:24:42 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1611858194; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=o/71Qa77uyEkpPOCs4B4HHO2B1c86Ro6Vi9Av6xPwCY=; b=ZqB8sPRY56YN649kJbhP6V1kXsRr+NzOuklWzvXy4DkH+FuH5gFO6c7xryTlNYXtXYDJr+ 6TJRU1DyxxvKL9gVf89ELZQ0+QY7QpTRI7X7Lu41VJtT3z1eFzK5WnpodT0TOeLsRs5DVL fICYNyE6pi24s4MtDEHqu/fxgPQapDE= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-353-lSEVa3TnMxmuKvKsNHPZ_A-1; Thu, 28 Jan 2021 13:23:10 -0500 X-MC-Unique: lSEVa3TnMxmuKvKsNHPZ_A-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id E2BCD1015C83; Thu, 28 Jan 2021 18:23:08 +0000 (UTC) Received: from bfoster (ovpn-114-23.rdu2.redhat.com [10.10.114.23]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 5BC0A5D9EF; Thu, 28 Jan 2021 18:23:08 +0000 (UTC) Date: Thu, 28 Jan 2021 13:23:06 -0500 From: Brian Foster To: "Darrick J. Wong" Cc: linux-xfs@vger.kernel.org, hch@infradead.org, david@fromorbit.com Subject: Re: [PATCH 09/13] xfs: refactor reflink functions to use xfs_trans_alloc_inode Message-ID: <20210128182306.GH2619139@bfoster> References: <161181366379.1523592.9213241916555622577.stgit@magnolia> <161181371557.1523592.14364313318301403930.stgit@magnolia> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <161181371557.1523592.14364313318301403930.stgit@magnolia> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Wed, Jan 27, 2021 at 10:01:55PM -0800, Darrick J. Wong wrote: > From: Darrick J. Wong > > The two remaining callers of xfs_trans_reserve_quota_nblks are in the > reflink code. These conversions aren't as uniform as the previous > conversions, so call that out in a separate patch. > > Signed-off-by: Darrick J. Wong > --- Modulo Christoph's feedback on the locking: Reviewed-by: Brian Foster > fs/xfs/xfs_reflink.c | 58 +++++++++++++++++++++----------------------------- > 1 file changed, 24 insertions(+), 34 deletions(-) > > > diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c > index 0778b5810c26..ded86cc4764c 100644 > --- a/fs/xfs/xfs_reflink.c > +++ b/fs/xfs/xfs_reflink.c > @@ -376,16 +376,15 @@ xfs_reflink_allocate_cow( > resblks = XFS_DIOSTRAT_SPACE_RES(mp, resaligned); > > xfs_iunlock(ip, *lockmode); > - error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, 0, &tp); > - *lockmode = XFS_ILOCK_EXCL; > - xfs_ilock(ip, *lockmode); > > - if (error) > + error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_write, resblks, 0, > + false, &tp); > + if (error) { > + /* This function must return with ILOCK_EXCL held. */ > + *lockmode = XFS_ILOCK_EXCL; > + xfs_ilock(ip, *lockmode); > return error; > - > - error = xfs_qm_dqattach_locked(ip, false); > - if (error) > - goto out_trans_cancel; > + } > > /* > * Check for an overlapping extent again now that we dropped the ilock. > @@ -398,12 +397,6 @@ xfs_reflink_allocate_cow( > goto convert; > } > > - error = xfs_trans_reserve_quota_nblks(tp, ip, resblks, 0, false); > - if (error) > - goto out_trans_cancel; > - > - xfs_trans_ijoin(tp, ip, 0); > - > /* Allocate the entire reservation as unwritten blocks. */ > nimaps = 1; > error = xfs_bmapi_write(tp, ip, imap->br_startoff, imap->br_blockcount, > @@ -997,7 +990,7 @@ xfs_reflink_remap_extent( > struct xfs_mount *mp = ip->i_mount; > struct xfs_trans *tp; > xfs_off_t newlen; > - int64_t qres, qdelta; > + int64_t qdelta = 0; > unsigned int resblks; > bool smap_real; > bool dmap_written = xfs_bmap_is_written_extent(dmap); > @@ -1005,15 +998,22 @@ xfs_reflink_remap_extent( > int nimaps; > int error; > > - /* Start a rolling transaction to switch the mappings */ > + /* > + * Start a rolling transaction to switch the mappings. > + * > + * Adding a written extent to the extent map can cause a bmbt split, > + * and removing a mapped extent from the extent can cause a bmbt split. > + * The two operations cannot both cause a split since they operate on > + * the same index in the bmap btree, so we only need a reservation for > + * one bmbt split if either thing is happening. However, we haven't > + * locked the inode yet, so we reserve assuming this is the case. > + */ > resblks = XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK); > - error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, 0, &tp); > + error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_write, resblks, 0, > + false, &tp); > if (error) > goto out; > > - xfs_ilock(ip, XFS_ILOCK_EXCL); > - xfs_trans_ijoin(tp, ip, 0); > - > /* > * Read what's currently mapped in the destination file into smap. > * If smap isn't a hole, we will have to remove it before we can add > @@ -1061,15 +1061,9 @@ xfs_reflink_remap_extent( > } > > /* > - * Compute quota reservation if we think the quota block counter for > + * Increase quota reservation if we think the quota block counter for > * this file could increase. > * > - * Adding a written extent to the extent map can cause a bmbt split, > - * and removing a mapped extent from the extent can cause a bmbt split. > - * The two operations cannot both cause a split since they operate on > - * the same index in the bmap btree, so we only need a reservation for > - * one bmbt split if either thing is happening. > - * > * If we are mapping a written extent into the file, we need to have > * enough quota block count reservation to handle the blocks in that > * extent. We log only the delta to the quota block counts, so if the > @@ -1083,13 +1077,9 @@ xfs_reflink_remap_extent( > * before we started. That should have removed all the delalloc > * reservations, but we code defensively. > */ > - qres = qdelta = 0; > - if (smap_real || dmap_written) > - qres = XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK); > - if (!smap_real && dmap_written) > - qres += dmap->br_blockcount; > - if (qres > 0) { > - error = xfs_trans_reserve_quota_nblks(tp, ip, qres, 0, false); > + if (!smap_real && dmap_written) { > + error = xfs_trans_reserve_quota_nblks(tp, ip, > + dmap->br_blockcount, 0, false); > if (error) > goto out_cancel; > } >