Index: lib/libcam/camlib.c
===================================================================
--- lib/libcam/camlib.c
+++ lib/libcam/camlib.c
@@ -619,7 +619,7 @@
 	/*
 	 * Zero the payload, the kernel does look at the flags.
 	 */
-	bzero(&(&ccb.ccb_h)[1], sizeof(struct ccb_trans_settings));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb.cts);
 
 	/*
 	 * Get transfer settings for this device.
Index: sbin/camcontrol/attrib.c
===================================================================
--- sbin/camcontrol/attrib.c
+++ sbin/camcontrol/attrib.c
@@ -137,8 +137,7 @@
 		goto bailout;
 	}
 
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(union ccb) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->csio);
 
 	STAILQ_INIT(&write_attr_list);
 
Index: sbin/camcontrol/camcontrol.c
===================================================================
--- sbin/camcontrol/camcontrol.c
+++ sbin/camcontrol/camcontrol.c
@@ -842,8 +842,7 @@
 	}
 
 	/* cam_getccb cleans up the header, caller has to zero the payload */
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(struct ccb_scsiio) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->csio);
 
 	inq_buf = (struct scsi_inquiry_data *)malloc(
 		sizeof(struct scsi_inquiry_data));
@@ -958,8 +957,7 @@
 	}
 
 	/* cam_getccb cleans up the header, caller has to zero the payload */
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(struct ccb_scsiio) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->csio);
 
 	serial_buf = (struct scsi_vpd_unit_serial_number *)
 		malloc(sizeof(*serial_buf));
@@ -1051,8 +1049,7 @@
 		return(1);
 	}
 
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(struct ccb_trans_settings) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->cts);
 
 	ccb->ccb_h.func_code = XPT_GET_TRAN_SETTINGS;
 	ccb->cts.type = CTS_TYPE_CURRENT_SETTINGS;
@@ -1605,8 +1602,7 @@
 		ata_flags |= AP_FLAG_TLEN_NO_DATA;
 	}
 
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(struct ccb_scsiio) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->csio);
 
 	scsi_ata_pass_16(&ccb->csio,
 			 retries,
@@ -1667,8 +1663,7 @@
 				      timeout, quiet);
 	}
 
-	bzero(&(&ccb->ccb_h)[1], sizeof(struct ccb_ataio) -
-	      sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->ataio);
 	cam_fill_ataio(&ccb->ataio,
 		       retries,
 		       NULL,
@@ -1737,8 +1732,7 @@
 		return (error);
 	}
 
-	bzero(&(&ccb->ccb_h)[1], sizeof(struct ccb_ataio) -
-	      sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->ataio);
 	cam_fill_ataio(&ccb->ataio,
 		       retries,
 		       NULL,
@@ -3187,8 +3181,7 @@
 	 * no-op, sending a rescan to the xpt bus would result in a status of
 	 * CAM_REQ_INVALID.
 	 */
-	bzero(&(&matchccb.ccb_h)[1],
-	      sizeof(struct ccb_dev_match) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&matchccb.cdm);
 	matchccb.ccb_h.func_code = XPT_DEV_MATCH;
 	matchccb.ccb_h.path_id = CAM_BUS_WILDCARD;
 	bufsize = sizeof(struct dev_match_result) * 20;
@@ -3536,8 +3529,7 @@
 	 * cam_getccb() zeros the CCB header only.  So we need to zero the
 	 * payload portion of the ccb.
 	 */
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(struct ccb_scsiio) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->csio);
 
 	scsi_read_defects(&ccb->csio,
 			  /*retries*/ retry_count,
@@ -3990,8 +3982,7 @@
 	if (ccb == NULL)
 		errx(1, "mode_sense: couldn't allocate CCB");
 
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(struct ccb_scsiio) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->csio);
 
 	scsi_mode_sense(&ccb->csio,
 			/* retries */ retry_count,
@@ -4040,8 +4031,7 @@
 	if (ccb == NULL)
 		errx(1, "mode_select: couldn't allocate CCB");
 
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(struct ccb_scsiio) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->csio);
 
 	scsi_mode_select(&ccb->csio,
 			 /* retries */ retry_count,
@@ -4158,8 +4148,7 @@
 		return(1);
 	}
 
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(union ccb) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(ccb);
 
 	while ((c = getopt(argc, argv, combinedopt)) != -1) {
 		switch(c) {
@@ -4660,8 +4649,7 @@
 	cam_path_string(device, pathstr, sizeof(pathstr));
 
 	if (numtags >= 0) {
-		bzero(&(&ccb->ccb_h)[1],
-		      sizeof(struct ccb_relsim) - sizeof(struct ccb_hdr));
+		CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->crs);
 		ccb->ccb_h.func_code = XPT_REL_SIMQ;
 		ccb->ccb_h.flags = CAM_DEV_QFREEZE;
 		ccb->crs.release_flags = RELSIM_ADJUST_OPENINGS;
@@ -4688,8 +4676,7 @@
 				pathstr, ccb->crs.openings);
 	}
 
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(struct ccb_getdevstats) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->cgds);
 
 	ccb->ccb_h.func_code = XPT_GDEV_STATS;
 
@@ -4889,8 +4876,7 @@
 		warnx("get_cpi: couldn't allocate CCB");
 		return(1);
 	}
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(struct ccb_pathinq) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->cpi);
 	ccb->ccb_h.func_code = XPT_PATH_INQ;
 	if (cam_send_ccb(device, ccb) < 0) {
 		warn("get_cpi: error sending Path Inquiry CCB");
@@ -4928,8 +4914,7 @@
 		warnx("get_cgd: couldn't allocate CCB");
 		return(1);
 	}
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(struct ccb_pathinq) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->cgd);
 	ccb->ccb_h.func_code = XPT_GDEV_TYPE;
 	if (cam_send_ccb(device, ccb) < 0) {
 		warn("get_cgd: error sending Path Inquiry CCB");
@@ -4974,8 +4959,7 @@
 	}
 	
 	/* cam_getccb cleans up the header, caller has to zero the payload */
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(struct ccb_scsiio) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->csio);
 
 	bzero(&sup_pages, sizeof(sup_pages));
 
@@ -5449,8 +5433,7 @@
 		return(1);
 	}
 
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(struct ccb_trans_settings) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->cts);
 
 	ccb->ccb_h.func_code = XPT_GET_TRAN_SETTINGS;
 
@@ -5590,8 +5573,7 @@
 			break;
 		}
 	}
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(struct ccb_pathinq) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->cpi);
 	/*
 	 * Grab path inquiry information, so we can determine whether
 	 * or not the initiator is capable of the things that the user
@@ -5617,8 +5599,7 @@
 		goto ratecontrol_bailout;
 	}
 	bcopy(&ccb->cpi, &cpi, sizeof(struct ccb_pathinq));
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(struct ccb_trans_settings) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->cts);
 	if (quiet == 0) {
 		fprintf(stdout, "%s parameters:\n",
 		    user_settings ? "User" : "Current");
@@ -5871,8 +5852,7 @@
 		return(1);
 	}
 
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(struct ccb_scsiio) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->csio);
 
 	while ((c = getopt(argc, argv, combinedopt)) != -1) {
 		switch(c) {
@@ -6020,8 +6000,7 @@
 	do {
 		cam_status status;
 
-		bzero(&(&ccb->ccb_h)[1],
-		      sizeof(struct ccb_scsiio) - sizeof(struct ccb_hdr));
+		CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->csio);
 
 		/*
 		 * There's really no need to do error recovery or
@@ -6168,8 +6147,7 @@
 		return(1);
 	}
 
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(struct ccb_scsiio) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->csio);
 
 	while ((c = getopt(argc, argv, combinedopt)) != -1) {
 		switch(c) {
@@ -6430,8 +6408,7 @@
 	do {
 		cam_status status;
 
-		bzero(&(&ccb->ccb_h)[1],
-		      sizeof(struct ccb_scsiio) - sizeof(struct ccb_hdr));
+		CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->csio);
 
 		/*
 		 * There's really no need to do error recovery or
@@ -6573,8 +6550,7 @@
 		return (1);
 	}
 
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(struct ccb_scsiio) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->csio);
 
 	countonly = 0;
 	lunsonly = 0;
@@ -6822,8 +6798,7 @@
 		return (1);
 	}
 
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(struct ccb_scsiio) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->csio);
 
 	while ((c = getopt(argc, argv, combinedopt)) != -1) {
 		switch (c) {
@@ -7027,8 +7002,7 @@
 		return (1);
 	}
 
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(union ccb) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->smpio);
 
 	while ((c = getopt(argc, argv, combinedopt)) != -1) {
 		switch (c) {
@@ -7221,8 +7195,7 @@
 		return (1);
 	}
 
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(union ccb) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->smpio);
 
 	while ((c = getopt(argc, argv, combinedopt)) != -1) {
 		switch (c) {
@@ -7284,8 +7257,7 @@
 	if ((response->long_response & SMP_RG_LONG_RESPONSE)
 	 && (long_response == 0)) {
 		ccb->ccb_h.status = CAM_REQ_INPROG;
-		bzero(&(&ccb->ccb_h)[1],
-		      sizeof(union ccb) - sizeof(struct ccb_hdr));
+		CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->smpio);
 		long_response = 1;
 		goto try_long;
 	}
@@ -7367,8 +7339,7 @@
 		return (1);
 	}
 
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(union ccb) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->smpio);
 
 	while ((c = getopt(argc, argv, combinedopt)) != -1) {
 		switch (c) {
@@ -7625,8 +7596,7 @@
 		return (1);
 	}
 
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(union ccb) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->smpio);
 
 	while ((c = getopt(argc, argv, combinedopt)) != -1) {
 		switch (c) {
@@ -7720,8 +7690,7 @@
 		goto bailout;
 	}
 
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(union ccb) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->cdai);
 
 	/*
 	 * On the first try, we just probe for the size of the data, and
@@ -8006,8 +7975,7 @@
 		return (1);
 	}
 
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(union ccb) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->smpio);
 	STAILQ_INIT(&devlist.dev_queue);
 
 	rgrequest = malloc(sizeof(*rgrequest));
@@ -8111,8 +8079,7 @@
 		char tmpstr[256];
 		int j;
 
-		bzero(&(&ccb->ccb_h)[1],
-		      sizeof(union ccb) - sizeof(struct ccb_hdr));
+		CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->smpio);
 
 		ccb->ccb_h.status = CAM_REQ_INPROG;
 		ccb->ccb_h.flags |= CAM_DEV_QFRZDIS;
@@ -8401,8 +8368,7 @@
 	}
 
 	/* cam_getccb cleans up the header, caller has to zero the payload */
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(struct ccb_scsiio) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->csio);
 
 	if (opcode_set != 0) {
 		options |= RSO_OPTIONS_OC;
@@ -8841,8 +8807,7 @@
 		return (1);
 	}
 
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(struct ccb_scsiio) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->csio);
 
 	ccb->ccb_h.func_code = XPT_REPROBE_LUN;
 
Index: sbin/camcontrol/fwdownload.c
===================================================================
--- sbin/camcontrol/fwdownload.c
+++ sbin/camcontrol/fwdownload.c
@@ -459,8 +459,7 @@
 	}
 
 	/* cam_getccb cleans up the header, caller has to zero the payload */
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(struct ccb_scsiio) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->csio);
 
 	bzero(&vpd_page, sizeof(vpd_page));
 
@@ -666,8 +665,7 @@
 		goto bailout;
 	}
 
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(union ccb) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(ccb);
 
 	if (devtype != CC_DT_SCSI) {
 		dxfer_len = sizeof(struct ata_params);
@@ -798,8 +796,7 @@
 		goto bailout;
 	}
 
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(union ccb) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(ccb);
 
 	max_pkt_size = vp->max_pkt_size;
 	if (max_pkt_size == 0)
@@ -830,8 +827,7 @@
 					       vp->cdb_byte2;
 			cdb.buffer_id = vp->inc_cdb_buffer_id ? pkt_count : 0;
 			/* Zero out payload of ccb union after ccb header. */
-			bzero(&(&ccb->ccb_h)[1],
-			    sizeof(struct ccb_scsiio) - sizeof(struct ccb_hdr));
+			CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->csio);
 			/*
 			 * Copy previously constructed cdb into ccb_scsiio
 			 * struct.
Index: sbin/camcontrol/persist.c
===================================================================
--- sbin/camcontrol/persist.c
+++ sbin/camcontrol/persist.c
@@ -450,8 +450,7 @@
 		goto bailout;
 	}
 
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(union ccb) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->csio);
 
 	while ((c = getopt(argc, argv, combinedopt)) != -1) {
 		switch (c) {
Index: sbin/iscontrol/fsm.c
===================================================================
--- sbin/iscontrol/fsm.c
+++ sbin/iscontrol/fsm.c
@@ -372,7 +372,7 @@
 	  debug(2, "pathstr=%s", pathstr);
 
 	  ccb = cam_getccb(sess->camdev);
-	  bzero(&(&ccb->ccb_h)[1], sizeof(struct ccb_relsim) - sizeof(struct ccb_hdr));
+	  CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->crs);
 	  ccb->ccb_h.func_code = XPT_REL_SIMQ;
 	  ccb->crs.release_flags = RELSIM_ADJUST_OPENINGS;
 	  ccb->crs.openings = sess->op->tags;
Index: sys/cam/cam_ccb.h
===================================================================
--- sys/cam/cam_ccb.h
+++ sys/cam/cam_ccb.h
@@ -1230,6 +1230,10 @@
 	struct	ccb_async		casync;
 };
 
+#define CCB_CLEAR_ALL_EXCEPT_HDR(ccbp)			\
+	bzero((char *)(ccbp) + sizeof((ccbp)->ccb_h),	\
+	    sizeof(*(ccbp)) - sizeof((ccbp)->ccb_h))
+
 __BEGIN_DECLS
 static __inline void
 cam_fill_csio(struct ccb_scsiio *csio, u_int32_t retries,
Index: usr.sbin/camdd/camdd.c
===================================================================
--- usr.sbin/camdd/camdd.c
+++ usr.sbin/camdd/camdd.c
@@ -1305,8 +1305,7 @@
 		goto bailout;
 	}
 
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(struct ccb_scsiio) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->csio);
 
 	scsi_read_capacity(&ccb->csio,
 			   /*retries*/ probe_retry_count,
@@ -1387,8 +1386,7 @@
 		goto bailout_error;
 	}
 
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(struct ccb_scsiio) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->cpi);
 
 	ccb->ccb_h.func_code = XPT_PATH_INQ;
 	ccb->ccb_h.flags = CAM_DIR_NONE;
@@ -2439,8 +2437,7 @@
 	data = &buf->buf_type_spec.data;
 
 	ccb = &data->ccb;
-	bzero(&(&ccb->ccb_h)[1],
-	      sizeof(struct ccb_scsiio) - sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->csio);
 
 	/*
 	 * In almost every case the number of blocks should be the device
Index: usr.sbin/mptutil/mpt_cam.c
===================================================================
--- usr.sbin/mptutil/mpt_cam.c
+++ usr.sbin/mptutil/mpt_cam.c
@@ -241,8 +241,7 @@
 		return (ENOMEM);
 
 	/* Zero the rest of the ccb. */
-	bzero(&(&ccb->ccb_h)[1], sizeof(struct ccb_scsiio) -
-	    sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->csio);
 
 	scsi_read_capacity(&ccb->csio, 1, NULL, MSG_SIMPLE_Q_TAG, &rcap,
 	    SSD_FULL_SIZE, 5000);
@@ -273,8 +272,7 @@
 	}
 
 	/* Zero the rest of the ccb. */
-	bzero(&(&ccb->ccb_h)[1], sizeof(struct ccb_scsiio) -
-	    sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->csio);
 
 	scsi_read_capacity_16(&ccb->csio, 1, NULL, MSG_SIMPLE_Q_TAG, 0, 0, 0,
 	    (uint8_t *)&rcaplong, sizeof(rcaplong), SSD_FULL_SIZE, 5000);
@@ -355,8 +353,7 @@
 		return (ENOMEM);
 
 	/* Zero the rest of the ccb. */
-	bzero(&(&ccb->ccb_h)[1], sizeof(struct ccb_scsiio) -
-	    sizeof(struct ccb_hdr));
+	CCB_CLEAR_ALL_EXCEPT_HDR(&ccb->csio);
 
 	inq_buf = calloc(1, sizeof(*inq_buf));
 	if (inq_buf == NULL) {