On Wed, Jan 22, 2020 at 11:42:22PM -0800, Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
>
> Convert xfs_buf_read_map() to return numeric error codes like most
> everywhere else in xfs. This involves moving the open-coded logic that
> reports metadata IO read / corruption errors and stales the buffer into
> xfs_buf_read_map so that the logic is all in one place.
>
> Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
.....
> diff --git a/fs/xfs/xfs_trans_buf.c b/fs/xfs/xfs_trans_buf.c
> index b5b3a78ef31c..56e7f8126cd7 100644
> --- a/fs/xfs/xfs_trans_buf.c
> +++ b/fs/xfs/xfs_trans_buf.c
> @@ -298,36 +298,17 @@ xfs_trans_read_buf_map(
> return 0;
> }
>
> - bp = xfs_buf_read_map(target, map, nmaps, flags, ops);
> - if (!bp) {
> - if (!(flags & XBF_TRYLOCK))
> - return -ENOMEM;
> - return tp ? 0 : -EAGAIN;
> - }
> -
> - /*
> - * If we've had a read error, then the contents of the buffer are
> - * invalid and should not be used. To ensure that a followup read tries
> - * to pull the buffer from disk again, we clear the XBF_DONE flag and
> - * mark the buffer stale. This ensures that anyone who has a current
> - * reference to the buffer will interpret it's contents correctly and
> - * future cache lookups will also treat it as an empty, uninitialised
> - * buffer.
> - */
> - if (bp->b_error) {
> - error = bp->b_error;
> - if (!XFS_FORCED_SHUTDOWN(mp))
> - xfs_buf_ioerror_alert(bp, __func__);
> - bp->b_flags &= ~XBF_DONE;
> - xfs_buf_stale(bp);
> -
> + error = xfs_buf_read_map(target, map, nmaps, flags, &bp, ops);
> + switch (error) {
> + case 0:
> + break;
> + case -EFSCORRUPTED:
> + case -EIO:
> if (tp && (tp->t_flags & XFS_TRANS_DIRTY))
> - xfs_force_shutdown(tp->t_mountp, SHUTDOWN_META_IO_ERROR);
> - xfs_buf_relse(bp);
> -
> - /* bad CRC means corrupted metadata */
> - if (error == -EFSBADCRC)
> - error = -EFSCORRUPTED;
> + xfs_force_shutdown(tp->t_mountp,
> + SHUTDOWN_META_IO_ERROR);
> + /* fall through */
> + default:
> return error;
> }
Same question as Christoph - we're only trying to avoid ENOMEM and
EAGAIN errors from shutting down the filesystem here, right?
Every other type of IO error that could end up on bp->b_error would
result in a shutdown, so perhaps this should be the other way
around:
switch (error) {
case 0:
break;
default:
/* shutdown stuff */
/* fall through */
case -ENOMEM:
case -EAGAIN:
return error;
}
Cheers,
Dave.
--
Dave Chinner
david@xxxxxxxxxxxxx
