From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from aserp1040.oracle.com ([141.146.126.69]:27028 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755727AbdJPTqa (ORCPT ); Mon, 16 Oct 2017 15:46:30 -0400 Date: Mon, 16 Oct 2017 12:46:25 -0700 From: "Darrick J. Wong" Subject: Re: [PATCH 02/30] xfs: create block pointer check functions Message-ID: <20171016194625.GF4703@magnolia> References: <150777244315.1724.6916081372861799350.stgit@magnolia> <150777245581.1724.14031376814151145502.stgit@magnolia> <20171012052852.GQ15067@dastard> <20171012054856.GR15067@dastard> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20171012054856.GR15067@dastard> Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: Dave Chinner Cc: linux-xfs@vger.kernel.org On Thu, Oct 12, 2017 at 04:48:56PM +1100, Dave Chinner wrote: > On Thu, Oct 12, 2017 at 04:28:52PM +1100, Dave Chinner wrote: > > On Wed, Oct 11, 2017 at 06:40:55PM -0700, Darrick J. Wong wrote: > > > From: Darrick J. Wong > > > > > > Create some helper functions to check that a block pointer points > > > within the filesystem (or AG) and doesn't point at static metadata. > > > We will use this for scrub. > > > > > > Signed-off-by: Darrick J. Wong > > > > Look fine > > now that I think about it and seen a bit more code.... > > > > > Reviewed-by: Dave Chinner > > > > > --- > > > fs/xfs/libxfs/xfs_alloc.c | 49 ++++++++++++++++++++++++++++++++++++++++++ > > > fs/xfs/libxfs/xfs_alloc.h | 4 +++ > > > fs/xfs/libxfs/xfs_rtbitmap.c | 12 ++++++++++ > > > fs/xfs/xfs_rtalloc.h | 2 ++ > > > 4 files changed, 67 insertions(+) > > > > > > > > > diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c > > > index 744dcae..bd3a943 100644 > > > --- a/fs/xfs/libxfs/xfs_alloc.c > > > +++ b/fs/xfs/libxfs/xfs_alloc.c > > > @@ -2923,3 +2923,52 @@ xfs_alloc_query_all( > > > query.fn = fn; > > > return xfs_btree_query_all(cur, xfs_alloc_query_range_helper, &query); > > > } > > > + > > > +/* Find the size of the AG, in blocks. */ > > > +xfs_agblock_t > > > +xfs_ag_block_count( > > > + struct xfs_mount *mp, > > > + xfs_agnumber_t agno) > > > +{ > > > + ASSERT(agno < mp->m_sb.sb_agcount); > > > + > > > + if (agno < mp->m_sb.sb_agcount - 1) > > > + return mp->m_sb.sb_agblocks; > > > + return mp->m_sb.sb_dblocks - (agno * mp->m_sb.sb_agblocks); > > > +} > > > + > > > +/* > > > + * Verify that an AG block number pointer neither points outside the AG > > > + * nor points at static metadata. > > > + */ > > > +bool > > > +xfs_verify_agbno_ptr( > > You can probably drop the "_ptr" prefix from these because I don't > think we every try to check/validate the agbno/fsbno of the static > metadata.... > > Some of the code just reads a bit weird with the "_ptr" suffix > in it... I wrangled with the name for a while too -- a generic block number could refer to any part of the AG, whereas a block number in a metadata structure is a pointer and should never point to static metadata, hence the _ptr suffix. On the other hand, some of the block pointers can be NULL{FS,AG}BLOCK and others can't, and we don't check that here so it's not quite a pointer check either. Meh. xfs_verify_agbno() it is. Anyone reading the comments will figure out why xfs_verify_agbno(mp, agno, XFS_AGFL_BLOCK(mp)) == false. > Still consider it reviewed.... Ok. --D > Cheers, > > Dave. > -- > Dave Chinner > david@fromorbit.com > -- > 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