On Mon, Jan 20, 2020 at 08:57:20AM +1100, Dave Chinner wrote:
> On Thu, Jan 16, 2020 at 10:23:44PM -0800, Darrick J. Wong wrote:
> > From: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
> >
> > Convert xfs_buf_read() to return numeric error codes like most
> > everywhere else in xfs. Hoist the callers' error logging and EFSBADCRC
> > remapping code into xfs_buf_read to reduce code duplication.
> >
> > Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
> > Reviewed-by: Christoph Hellwig <hch@xxxxxx>
> > ---
> > fs/xfs/libxfs/xfs_attr_remote.c | 16 +++-------------
> > fs/xfs/xfs_buf.c | 33 +++++++++++++++++++++++++++++++++
> > fs/xfs/xfs_buf.h | 14 +++-----------
> > fs/xfs/xfs_log_recover.c | 26 +++++++-------------------
> > fs/xfs/xfs_symlink.c | 17 ++++-------------
> > 5 files changed, 50 insertions(+), 56 deletions(-)
> >
> >
> > diff --git a/fs/xfs/libxfs/xfs_attr_remote.c b/fs/xfs/libxfs/xfs_attr_remote.c
> > index a266d05df146..46c516809086 100644
> > --- a/fs/xfs/libxfs/xfs_attr_remote.c
> > +++ b/fs/xfs/libxfs/xfs_attr_remote.c
> > @@ -418,20 +418,10 @@ xfs_attr_rmtval_get(
> > (map[i].br_startblock != HOLESTARTBLOCK));
> > dblkno = XFS_FSB_TO_DADDR(mp, map[i].br_startblock);
> > dblkcnt = XFS_FSB_TO_BB(mp, map[i].br_blockcount);
> > - bp = xfs_buf_read(mp->m_ddev_targp, dblkno, dblkcnt, 0,
> > - &xfs_attr3_rmt_buf_ops);
> > - if (!bp)
> > - return -ENOMEM;
> > - error = bp->b_error;
> > - if (error) {
> > - xfs_buf_ioerror_alert(bp, __func__);
> > - xfs_buf_relse(bp);
> > -
> > - /* bad CRC means corrupted metadata */
> > - if (error == -EFSBADCRC)
> > - error = -EFSCORRUPTED;
> > + error = xfs_buf_read(mp->m_ddev_targp, dblkno, dblkcnt,
> > + 0, &bp, &xfs_attr3_rmt_buf_ops);
> > + if (error)
> > return error;
> > - }
> >
> > error = xfs_attr_rmtval_copyout(mp, bp, args->dp->i_ino,
> > &offset, &valuelen,
> > diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c
> > index a00e63d08a3b..8c9cd1ab870b 100644
> > --- a/fs/xfs/xfs_buf.c
> > +++ b/fs/xfs/xfs_buf.c
> > @@ -851,6 +851,39 @@ xfs_buf_read_map(
> > return bp;
> > }
> >
> > +int
> > +xfs_buf_read(
> > + struct xfs_buftarg *target,
> > + xfs_daddr_t blkno,
> > + size_t numblks,
> > + xfs_buf_flags_t flags,
> > + struct xfs_buf **bpp,
> > + const struct xfs_buf_ops *ops)
> > +{
> > + struct xfs_buf *bp;
> > + int error;
> > + DEFINE_SINGLE_BUF_MAP(map, blkno, numblks);
> > +
> > + *bpp = NULL;
> > + bp = xfs_buf_read_map(target, &map, 1, flags, ops);
> > + if (!bp)
> > + return -ENOMEM;
> > + error = bp->b_error;
> > + if (error) {
> > + xfs_buf_ioerror_alert(bp, __func__);
> > + xfs_buf_stale(bp);
> > + xfs_buf_relse(bp);
> > +
> > + /* bad CRC means corrupted metadata */
> > + if (error == -EFSBADCRC)
> > + error = -EFSCORRUPTED;
> > + return error;
> > + }
> > +
> > + *bpp = bp;
> > + return 0;
> > +}
>
> I'd just put all this in xfs_buf_read_map() and leave
> xfs_buf_read() as a simple wrapper around xfs_buf_read_map().
>
> Also:
>
> if (!bp->b_error) {
> *bpp = bp;
> return 0;
> }
> /* handle error without extra indenting */
Yeah, Christoph nudged me towards that at the end of last week, too.
>
> > - const struct xfs_buf_ops *ops)
> > -{
> > - DEFINE_SINGLE_BUF_MAP(map, blkno, numblks);
> > - return xfs_buf_read_map(target, &map, 1, flags, ops);
> > -}
> > +int xfs_buf_read(struct xfs_buftarg *target, xfs_daddr_t blkno, size_t numblks,
> > + xfs_buf_flags_t flags, struct xfs_buf **bpp,
> > + const struct xfs_buf_ops *ops);
> >
> > static inline void
> > xfs_buf_readahead(
> > diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
> > index 0d683fb96396..ac79537d3275 100644
> > --- a/fs/xfs/xfs_log_recover.c
> > +++ b/fs/xfs/xfs_log_recover.c
> > @@ -2745,15 +2745,10 @@ xlog_recover_buffer_pass2(
> > if (buf_f->blf_flags & XFS_BLF_INODE_BUF)
> > buf_flags |= XBF_UNMAPPED;
> >
> > - bp = xfs_buf_read(mp->m_ddev_targp, buf_f->blf_blkno, buf_f->blf_len,
> > - buf_flags, NULL);
> > - if (!bp)
> > - return -ENOMEM;
> > - error = bp->b_error;
> > - if (error) {
> > - xfs_buf_ioerror_alert(bp, "xlog_recover_do..(read#1)");
> > - goto out_release;
> > - }
> > + error = xfs_buf_read(mp->m_ddev_targp, buf_f->blf_blkno, buf_f->blf_len,
> > + buf_flags, &bp, NULL);
> > + if (error)
> > + return error;
>
> I'd argue that if we are touching every remaining xfs_buf_read() call
> like this, we should get rid of it and just call xfs_buf_read_map()
> instead.
FWIW I changed out this patch to leave xfs_buf_read as a static inline
and shoved all the buffer state and ioerror_alert refactoring to the end
of the series, so at least this part is a straight conversion.
--D
> Cheers,
>
> Dave.
> --
> Dave Chinner
> david@xxxxxxxxxxxxx
