From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:45890 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751487AbeENK01 (ORCPT ); Mon, 14 May 2018 06:26:27 -0400 Date: Mon, 14 May 2018 06:26:25 -0400 From: Brian Foster Subject: Re: [PATCH 8/8] xfs: teach xfs_bmapi_remap to accept some bmapi flags Message-ID: <20180514102625.GB8919@bfoster.bfoster> References: <152597988038.25215.9276761144353662866.stgit@magnolia> <152597993604.25215.2923117604057991749.stgit@magnolia> <20180511152026.GI105683@bfoster.bfoster> <20180511231403.GJ11261@magnolia> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180511231403.GJ11261@magnolia> Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: "Darrick J. Wong" Cc: linux-xfs@vger.kernel.org On Fri, May 11, 2018 at 04:14:03PM -0700, Darrick J. Wong wrote: > On Fri, May 11, 2018 at 11:20:27AM -0400, Brian Foster wrote: > > On Thu, May 10, 2018 at 12:18:56PM -0700, Darrick J. Wong wrote: > > > From: Darrick J. Wong > > > > > > Teach xfs_bmapi_remap how to map in unwritten extent and to skip rmap > > > updates. This enables us to rebuild real and unwritten extents from the > > > rmapbt. > > > > > > Signed-off-by: Darrick J. Wong > > > --- > > > fs/xfs/libxfs/xfs_bmap.c | 9 +++++++-- > > > 1 file changed, 7 insertions(+), 2 deletions(-) > > > > > > > > > diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c > > > index b63e15a114f3..7660efb5beb0 100644 > > > --- a/fs/xfs/libxfs/xfs_bmap.c > > > +++ b/fs/xfs/libxfs/xfs_bmap.c > > > @@ -4543,7 +4543,9 @@ xfs_bmapi_remap( > > > ASSERT(len > 0); > > > ASSERT(len <= (xfs_filblks_t)MAXEXTLEN); > > > ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL)); > > > - ASSERT(!(flags & ~(XFS_BMAPI_ATTRFORK))); > > > + ASSERT(!(flags & ~(XFS_BMAPI_ATTRFORK | XFS_BMAPI_PREALLOC | > > > + XFS_BMAPI_NORMAP))); > > > + ASSERT(!(flags & XFS_BMAPI_ATTRFORK) || !(flags & XFS_BMAPI_PREALLOC)); > > > > A little confusing.. how about something like? > > > > ASSERT((flags & XFS_BMAPI_ATTRFORK|XFS_BMAPI_PREALLOC) != > > XFS_BMAPI_ATTRFORK|XFS_BMAPI_PREALLOC); > > Ok. > > > > > > > if (unlikely(XFS_TEST_ERROR( > > > (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS && > > > @@ -4581,7 +4583,10 @@ xfs_bmapi_remap( > > > got.br_startoff = bno; > > > got.br_startblock = startblock; > > > got.br_blockcount = len; > > > - got.br_state = XFS_EXT_NORM; > > > + if (flags & XFS_BMAPI_PREALLOC) > > > + got.br_state = XFS_EXT_UNWRITTEN; > > > + else > > > + got.br_state = XFS_EXT_NORM; > > > > It's hard to see the wider picture without any users of this, but I do > > notice that the one current caller appears to have everything passed > > down to it to construct an xfs_bmbt_irec (in fact the data appears to > > come from an irec in the first place). > > Later on in the online repair series (which I will send out after the > review for this series concludes) I'll make use of xfs_bmapi_remap to > reconstruct the bmbt from the rmap, which is why I've been busy adding > BMAPI_ATTRFORK, BMAPI_NORMAP, and BMAPI_PREALLOC to this function. > > This patch[1] in my branch demonstrates the new uses of this function. > Thanks. FWIW, this caller also looks like it ultimately passes down data from an xfs_bmbt_irec. Perhaps this or some of the others would need a local copy of the record to handle incremental/partial calls as such, but I wonder how much code would be cleaned out by just passing down an irec directly rather than unrolling the fields and turning it back into an xfs_bmbt_irec in xfs_bmapi_remap(). But that's a cleanup for another patch... Brian > --D > > [1] https://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux.git/commit/?h=djwong-devel&id=7d8601ba8a938179ec0dae18b8a0848122eaf5e5 > > > Brian > > > > > > > > error = xfs_bmap_add_extent_hole_real(tp, ip, whichfork, &icur, > > > &cur, &got, &firstblock, dfops, &logflags, flags); > > > > > > -- > > > To unsubscribe from this list: send the line "unsubscribe linux-xfs" in > > > the body of a message to majordomo@vger.kernel.org > > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-xfs" in > > the body of a message to majordomo@vger.kernel.org > > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- > To unsubscribe from this list: send the line "unsubscribe linux-xfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html