replace pointer arithmetic and casts with offsetof

ok dlg@ krw@

diff --git a/sys/dev/ic/mpi.c b/sys/dev/ic/mpi.c
index 4418785..82df1cb 100644 (file)
--- a/sys/dev/ic/mpi.c
+++ b/sys/dev/ic/mpi.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: mpi.c,v 1.202 2015/09/09 18:23:55 deraadt Exp $ */
+/*     $OpenBSD: mpi.c,v 1.203 2015/10/23 00:08:57 jsg Exp $ */
 
 /*
  * Copyright (c) 2005, 2006, 2009 David Gwynne <dlg@openbsd.org>
@@ -759,7 +759,7 @@ mpi_inq(struct mpi_softc *sc, u_int16_t target, int physdisk)
 {
        struct mpi_ccb                  *ccb;
        struct scsi_inquiry             inq;
-       struct {
+       struct inq_bundle {
                struct mpi_msg_scsi_io          io;
                struct mpi_sge                  sge;
                struct scsi_inquiry_data        inqbuf;
@@ -809,14 +809,14 @@ mpi_inq(struct mpi_softc *sc, u_int16_t target, int physdisk)
        htolem32(&io->data_length, sizeof(struct scsi_inquiry_data));
 
        htolem32(&io->sense_buf_low_addr, ccb->ccb_cmd_dva +
-           ((u_int8_t *)&bundle->sense - (u_int8_t *)bundle));
+           offsetof(struct inq_bundle, sense));
 
        htolem32(&sge->sg_hdr, MPI_SGE_FL_TYPE_SIMPLE | MPI_SGE_FL_SIZE_64 |
            MPI_SGE_FL_LAST | MPI_SGE_FL_EOB | MPI_SGE_FL_EOL |
            (u_int32_t)sizeof(inq));
 
        mpi_dvatosge(sge, ccb->ccb_cmd_dva +
-           ((u_int8_t *)&bundle->inqbuf - (u_int8_t *)bundle));
+           offsetof(struct inq_bundle, inqbuf));
 
        if (mpi_poll(sc, ccb, 5000) != 0)
                return (1);
@@ -1369,7 +1369,7 @@ mpi_scsi_cmd(struct scsi_xfer *xs)
        htolem32(&io->data_length, xs->datalen);
 
        htolem32(&io->sense_buf_low_addr, ccb->ccb_cmd_dva +
-           ((u_int8_t *)&mcb->mcb_sense - (u_int8_t *)mcb));
+           offsetof(struct mpi_ccb_bundle, mcb_sense));
 
        if (mpi_load_xs(ccb) != 0)
                goto stuffup;