Index: head/sys/cam/ata/ata_da.c
===================================================================
--- head/sys/cam/ata/ata_da.c
+++ head/sys/cam/ata/ata_da.c
@@ -911,7 +911,7 @@
 	int error;
 
 	periph = (struct cam_periph *)dp->d_drv1;
-	if (cam_periph_acquire(periph) != CAM_REQ_CMP) {
+	if (cam_periph_acquire(periph) != 0) {
 		return(ENXIO);
 	}
 
@@ -1328,7 +1328,7 @@
 			softc->state = ADA_STATE_LOGDIR;
 		else
 		    break;
-		if (cam_periph_acquire(periph) != CAM_REQ_CMP)
+		if (cam_periph_acquire(periph) != 0)
 			softc->state = ADA_STATE_NORMAL;
 		else
 			xpt_schedule(periph, CAM_PRIORITY_DEV);
@@ -1841,7 +1841,7 @@
 	 * We'll release this reference once GEOM calls us back (via
 	 * adadiskgonecb()) telling us that our provider has been freed.
 	 */
-	if (cam_periph_acquire(periph) != CAM_REQ_CMP) {
+	if (cam_periph_acquire(periph) != 0) {
 		xpt_print(periph->path, "%s: lost periph during "
 			  "registration!\n", __func__);
 		cam_periph_lock(periph);
@@ -1866,7 +1866,7 @@
 	 * Create our sysctl variables, now that we know
 	 * we have successfully attached.
 	 */
-	if (cam_periph_acquire(periph) == CAM_REQ_CMP)
+	if (cam_periph_acquire(periph) == 0)
 		taskqueue_enqueue(taskqueue_thread, &softc->sysctl_task);
 
 	/*
Index: head/sys/cam/ata/ata_pmp.c
===================================================================
--- head/sys/cam/ata/ata_pmp.c
+++ head/sys/cam/ata/ata_pmp.c
@@ -315,7 +315,7 @@
 		if (code == AC_SENT_BDR || code == AC_BUS_RESET)
 			softc->found = 0; /* We have to reset everything. */
 		if (softc->state == PMP_STATE_NORMAL) {
-			if (cam_periph_acquire(periph) == CAM_REQ_CMP) {
+			if (cam_periph_acquire(periph) == 0) {
 				if (softc->pm_pid == 0x37261095 ||
 				    softc->pm_pid == 0x38261095)
 					softc->state = PMP_STATE_PM_QUIRKS_1;
@@ -343,7 +343,7 @@
 	char tmpstr[32], tmpstr2[16];
 
 	periph = (struct cam_periph *)context;
-	if (cam_periph_acquire(periph) != CAM_REQ_CMP)
+	if (cam_periph_acquire(periph) != 0)
 		return;
 
 	softc = (struct pmp_softc *)periph->softc;
Index: head/sys/cam/ata/ata_xpt.c
===================================================================
--- head/sys/cam/ata/ata_xpt.c
+++ head/sys/cam/ata/ata_xpt.c
@@ -280,7 +280,6 @@
 proberegister(struct cam_periph *periph, void *arg)
 {
 	union ccb *request_ccb;	/* CCB representing the probe request */
-	cam_status status;
 	probe_softc *softc;
 
 	request_ccb = (union ccb *)arg;
@@ -304,10 +303,9 @@
 	periph->softc = softc;
 	softc->periph = periph;
 	softc->action = PROBE_INVALID;
-	status = cam_periph_acquire(periph);
-	if (status != CAM_REQ_CMP) {
-		return (status);
-	}
+	if (cam_periph_acquire(periph) != 0)
+		return (CAM_REQ_CMP_ERR);
+
 	CAM_DEBUG(periph->path, CAM_DEBUG_PROBE, ("Probe started\n"));
 	ata_device_transport(periph->path);
 	probeschedule(periph);
Index: head/sys/cam/cam_periph.h
===================================================================
--- head/sys/cam/cam_periph.h
+++ head/sys/cam/cam_periph.h
@@ -159,7 +159,7 @@
 			    ac_callback_t *, ac_code, void *arg);
 struct cam_periph *cam_periph_find(struct cam_path *path, char *name);
 int		cam_periph_list(struct cam_path *, struct sbuf *);
-cam_status	cam_periph_acquire(struct cam_periph *periph);
+int		cam_periph_acquire(struct cam_periph *periph);
 void		cam_periph_doacquire(struct cam_periph *periph);
 void		cam_periph_release(struct cam_periph *periph);
 void		cam_periph_release_locked(struct cam_periph *periph);
Index: head/sys/cam/cam_periph.c
===================================================================
--- head/sys/cam/cam_periph.c
+++ head/sys/cam/cam_periph.c
@@ -403,19 +403,19 @@
 	return (count);
 }
 
-cam_status
+int
 cam_periph_acquire(struct cam_periph *periph)
 {
-	cam_status status;
+	int status;
 
-	status = CAM_REQ_CMP_ERR;
 	if (periph == NULL)
-		return (status);
+		return (EINVAL);
 
+	status = ENOENT;
 	xpt_lock_buses();
 	if ((periph->flags & CAM_PERIPH_INVALID) == 0) {
 		periph->refcount++;
-		status = CAM_REQ_CMP;
+		status = 0;
 	}
 	xpt_unlock_buses();
 
@@ -482,7 +482,7 @@
 	 * from user us while we sleep.
 	 */
 
-	if (cam_periph_acquire(periph) != CAM_REQ_CMP)
+	if (cam_periph_acquire(periph) != 0)
 		return (ENXIO);
 
 	cam_periph_assert(periph, MA_OWNED);
Index: head/sys/cam/ctl/scsi_ctl.c
===================================================================
--- head/sys/cam/ctl/scsi_ctl.c
+++ head/sys/cam/ctl/scsi_ctl.c
@@ -459,7 +459,7 @@
 	struct ctlfe_lun_softc *softc;
 	union ccb ccb;
 	cam_status status;
-	int i;
+	int i, acstatus;
 
 	softc = (struct ctlfe_lun_softc *)arg;
 	bus_softc = softc->parent_softc;
@@ -539,11 +539,11 @@
 		}
 	}
 
-	status = cam_periph_acquire(periph);
-	if ((status & CAM_STATUS_MASK) != CAM_REQ_CMP) {
+	acstatus = cam_periph_acquire(periph);
+	if (acstatus != 0) {
 		xpt_print(periph->path, "%s: could not acquire reference "
-			  "count, status = %#x\n", __func__, status);
-		return (status);
+			  "count, status = %#x\n", __func__, acstatus);
+		return (CAM_REQ_CMP_ERR);
 	}
 
 	if (i == 0) {
Index: head/sys/cam/mmc/mmc_da.c
===================================================================
--- head/sys/cam/mmc/mmc_da.c
+++ head/sys/cam/mmc/mmc_da.c
@@ -369,7 +369,7 @@
 	int error;
 
 	periph = (struct cam_periph *)dp->d_drv1;
-	if (cam_periph_acquire(periph) != CAM_REQ_CMP) {
+	if (cam_periph_acquire(periph) != 0) {
 		return(ENXIO);
 	}
 
@@ -744,7 +744,7 @@
 	 * We'll release this reference once GEOM calls us back (via
 	 * sddadiskgonecb()) telling us that our provider has been freed.
 	 */
-	if (cam_periph_acquire(periph) != CAM_REQ_CMP) {
+	if (cam_periph_acquire(periph) != 0) {
 		xpt_print(periph->path, "%s: lost periph during "
 			  "registration!\n", __func__);
 		cam_periph_lock(periph);
Index: head/sys/cam/mmc/mmc_xpt.c
===================================================================
--- head/sys/cam/mmc/mmc_xpt.c
+++ head/sys/cam/mmc/mmc_xpt.c
@@ -471,9 +471,9 @@
 static cam_status
 mmcprobe_register(struct cam_periph *periph, void *arg)
 {
-	union ccb *request_ccb;	/* CCB representing the probe request */
-	cam_status status;
 	mmcprobe_softc *softc;
+	union ccb *request_ccb;	/* CCB representing the probe request */
+	int status;
 
 	CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("mmcprobe_register\n"));
 
@@ -501,10 +501,10 @@
 	status = cam_periph_acquire(periph);
 
         memset(&periph->path->device->mmc_ident_data, 0, sizeof(struct mmc_params));
-	if (status != CAM_REQ_CMP) {
+	if (status != 0) {
 		printf("proberegister: cam_periph_acquire failed (status=%d)\n",
 			status);
-		return (status);
+		return (CAM_REQ_CMP_ERR);
 	}
 	CAM_DEBUG(periph->path, CAM_DEBUG_PROBE, ("Probe started\n"));
 
Index: head/sys/cam/nvme/nvme_da.c
===================================================================
--- head/sys/cam/nvme/nvme_da.c
+++ head/sys/cam/nvme/nvme_da.c
@@ -260,7 +260,7 @@
 	int error;
 
 	periph = (struct cam_periph *)dp->d_drv1;
-	if (cam_periph_acquire(periph) != CAM_REQ_CMP) {
+	if (cam_periph_acquire(periph) != 0) {
 		return(ENXIO);
 	}
 
@@ -785,7 +785,7 @@
 	 * We'll release this reference once GEOM calls us back (via
 	 * ndadiskgonecb()) telling us that our provider has been freed.
 	 */
-	if (cam_periph_acquire(periph) != CAM_REQ_CMP) {
+	if (cam_periph_acquire(periph) != 0) {
 		xpt_print(periph->path, "%s: lost periph during "
 			  "registration!\n", __func__);
 		cam_periph_lock(periph);
@@ -807,7 +807,7 @@
 	 * Create our sysctl variables, now that we know
 	 * we have successfully attached.
 	 */
-	if (cam_periph_acquire(periph) == CAM_REQ_CMP)
+	if (cam_periph_acquire(periph) == 0)
 		taskqueue_enqueue(taskqueue_thread, &softc->sysctl_task);
 
 	/*
Index: head/sys/cam/nvme/nvme_xpt.c
===================================================================
--- head/sys/cam/nvme/nvme_xpt.c
+++ head/sys/cam/nvme/nvme_xpt.c
@@ -198,7 +198,6 @@
 nvme_probe_register(struct cam_periph *periph, void *arg)
 {
 	union ccb *request_ccb;	/* CCB representing the probe request */
-	cam_status status;
 	nvme_probe_softc *softc;
 
 	request_ccb = (union ccb *)arg;
@@ -222,10 +221,9 @@
 	periph->softc = softc;
 	softc->periph = periph;
 	softc->action = NVME_PROBE_INVALID;
-	status = cam_periph_acquire(periph);
-	if (status != CAM_REQ_CMP) {
-		return (status);
-	}
+	if (cam_periph_acquire(periph) != 0)
+		return (CAM_REQ_CMP_ERR);
+
 	CAM_DEBUG(periph->path, CAM_DEBUG_PROBE, ("Probe started\n"));
 
 //	nvme_device_transport(periph->path);
Index: head/sys/cam/scsi/scsi_cd.c
===================================================================
--- head/sys/cam/scsi/scsi_cd.c
+++ head/sys/cam/scsi/scsi_cd.c
@@ -445,7 +445,7 @@
 	case AC_SCSI_AEN:
 		softc = (struct cd_softc *)periph->softc;
 		if (softc->state == CD_STATE_NORMAL && !softc->tur) {
-			if (cam_periph_acquire(periph) == CAM_REQ_CMP) {
+			if (cam_periph_acquire(periph) == 0) {
 				softc->tur = 1;
 				xpt_schedule(periph, CAM_PRIORITY_NORMAL);
 			}
@@ -480,7 +480,7 @@
 	char tmpstr[32], tmpstr2[16];
 
 	periph = (struct cam_periph *)context;
-	if (cam_periph_acquire(periph) != CAM_REQ_CMP)
+	if (cam_periph_acquire(periph) != 0)
 		return;
 
 	softc = (struct cd_softc *)periph->softc;
@@ -676,7 +676,7 @@
 	 * We'll release this reference once GEOM calls us back (via
 	 * dadiskgonecb()) telling us that our provider has been freed.
 	 */
-	if (cam_periph_acquire(periph) != CAM_REQ_CMP) {
+	if (cam_periph_acquire(periph) != 0) {
 		xpt_print(periph->path, "%s: lost periph during "
 			  "registration!\n", __func__);
 		cam_periph_lock(periph);
@@ -717,7 +717,7 @@
 	periph = (struct cam_periph *)dp->d_drv1;
 	softc = (struct cd_softc *)periph->softc;
 
-	if (cam_periph_acquire(periph) != CAM_REQ_CMP)
+	if (cam_periph_acquire(periph) != 0)
 		return(ENXIO);
 
 	cam_periph_lock(periph);
@@ -2601,7 +2601,7 @@
 
 	if (softc->state == CD_STATE_NORMAL && !softc->tur &&
 	    softc->outstanding_cmds == 0) {
-		if (cam_periph_acquire(periph) == CAM_REQ_CMP) {
+		if (cam_periph_acquire(periph) == 0) {
 			softc->tur = 1;
 			xpt_schedule(periph, CAM_PRIORITY_NORMAL);
 		}
Index: head/sys/cam/scsi/scsi_da.c
===================================================================
--- head/sys/cam/scsi/scsi_da.c
+++ head/sys/cam/scsi/scsi_da.c
@@ -1565,7 +1565,7 @@
 	token_sanity(token);
 	DA_PERIPH_PRINT(periph, "acquiring device %s (%d): %d\n",
 	    da_ref_text[token], token, err);
-	if (err == CAM_REQ_CMP) {
+	if (err == 0) {
 		int cnt;
 		struct da_softc *softc = periph->softc;
 
@@ -1628,7 +1628,7 @@
 	int error;
 
 	periph = (struct cam_periph *)dp->d_drv1;
-	if (da_periph_acquire(periph, DA_REF_OPEN) != CAM_REQ_CMP) {
+	if (da_periph_acquire(periph, DA_REF_OPEN) != 0) {
 		return (ENXIO);
 	}
 
@@ -2061,7 +2061,7 @@
 	case AC_SCSI_AEN:
 		softc = (struct da_softc *)periph->softc;
 		if (!cam_iosched_has_work_flags(softc->cam_iosched, DA_WORK_TUR)) {
-			if (da_periph_acquire(periph, DA_REF_TUR) == CAM_REQ_CMP) {
+			if (da_periph_acquire(periph, DA_REF_TUR) == 0) {
 				cam_iosched_set_work_flags(softc->cam_iosched, DA_WORK_TUR);
 				daschedule(periph);
 			}
@@ -2732,7 +2732,7 @@
 	 * We'll release this reference once GEOM calls us back (via
 	 * dadiskgonecb()) telling us that our provider has been freed.
 	 */
-	if (da_periph_acquire(periph, DA_REF_GEOM) != CAM_REQ_CMP) {
+	if (da_periph_acquire(periph, DA_REF_GEOM) != 0) {
 		xpt_print(periph->path, "%s: lost periph during "
 			  "registration!\n", __func__);
 		cam_periph_lock(periph);
@@ -4700,7 +4700,7 @@
 			 * we have successfully attached.
 			 */
 			/* increase the refcount */
-			if (da_periph_acquire(periph, DA_REF_SYSCTL) == CAM_REQ_CMP) {
+			if (da_periph_acquire(periph, DA_REF_SYSCTL) == 0) {
 
 				taskqueue_enqueue(taskqueue_thread,
 						  &softc->sysctl_task);
@@ -5558,7 +5558,7 @@
 dareprobe(struct cam_periph *periph)
 {
 	struct da_softc	  *softc;
-	cam_status status;
+	int status;
 
 	softc = (struct da_softc *)periph->softc;
 
@@ -5567,8 +5567,7 @@
 		return;
 
 	status = da_periph_acquire(periph, DA_REF_REPROBE);
-	KASSERT(status == CAM_REQ_CMP,
-	    ("dareprobe: cam_periph_acquire failed"));
+	KASSERT(status == 0, ("dareprobe: cam_periph_acquire failed"));
 
 	softc->state = DA_STATE_PROBE_WP;
 	xpt_schedule(periph, CAM_PRIORITY_DEV);
@@ -5666,7 +5665,7 @@
 
 	if (!cam_iosched_has_work_flags(softc->cam_iosched, DA_WORK_TUR) &&
 	    LIST_EMPTY(&softc->pending_ccbs)) {
-		if (da_periph_acquire(periph, DA_REF_TUR) == CAM_REQ_CMP) {
+		if (da_periph_acquire(periph, DA_REF_TUR) == 0) {
 			cam_iosched_set_work_flags(softc->cam_iosched, DA_WORK_TUR);
 			daschedule(periph);
 		}
Index: head/sys/cam/scsi/scsi_enc.c
===================================================================
--- head/sys/cam/scsi/scsi_enc.c
+++ head/sys/cam/scsi/scsi_enc.c
@@ -267,7 +267,7 @@
 	int error = 0;
 
 	periph = (struct cam_periph *)dev->si_drv1;
-	if (cam_periph_acquire(periph) != CAM_REQ_CMP)
+	if (cam_periph_acquire(periph) != 0)
 		return (ENXIO);
 
 	cam_periph_lock(periph);
@@ -859,7 +859,7 @@
 
 	callout_init_mtx(&enc->status_updater, cam_periph_mtx(enc->periph), 0);
 
-	if (cam_periph_acquire(enc->periph) != CAM_REQ_CMP)
+	if (cam_periph_acquire(enc->periph) != 0)
 		return (ENXIO);
 
 	result = kproc_create(enc_daemon, enc, &enc->enc_daemon, /*flags*/0,
@@ -975,7 +975,7 @@
 	 * instance for it.  We'll release this reference once the devfs
 	 * instance has been freed.
 	 */
-	if (cam_periph_acquire(periph) != CAM_REQ_CMP) {
+	if (cam_periph_acquire(periph) != 0) {
 		xpt_print(periph->path, "%s: lost periph during "
 			  "registration!\n", __func__);
 		cam_periph_lock(periph);
Index: head/sys/cam/scsi/scsi_pass.c
===================================================================
--- head/sys/cam/scsi/scsi_pass.c
+++ head/sys/cam/scsi/scsi_pass.c
@@ -518,7 +518,6 @@
 		buftype = (uintptr_t)arg;
 		if (buftype == CDAI_TYPE_PHYS_PATH) {
 			struct pass_softc *softc;
-			cam_status status;
 
 			softc = (struct pass_softc *)periph->softc;
 			/*
@@ -527,8 +526,7 @@
 			 * a situation where the periph goes away before
 			 * the task queue has a chance to run.
 			 */
-			status = cam_periph_acquire(periph);
-			if (status != CAM_REQ_CMP)
+			if (cam_periph_acquire(periph) != 0)
 				break;
 
 			taskqueue_enqueue(taskqueue_thread,
@@ -626,7 +624,7 @@
 	 * Acquire a reference to the periph that we can release once we've
 	 * cleaned up the kqueue.
 	 */
-	if (cam_periph_acquire(periph) != CAM_REQ_CMP) {
+	if (cam_periph_acquire(periph) != 0) {
 		xpt_print(periph->path, "%s: lost periph during "
 			  "registration!\n", __func__);
 		cam_periph_lock(periph);
@@ -638,7 +636,7 @@
 	 * instance for it.  We'll release this reference once the devfs
 	 * instance has been freed.
 	 */
-	if (cam_periph_acquire(periph) != CAM_REQ_CMP) {
+	if (cam_periph_acquire(periph) != 0) {
 		xpt_print(periph->path, "%s: lost periph during "
 			  "registration!\n", __func__);
 		cam_periph_lock(periph);
@@ -665,7 +663,7 @@
 	 * Hold a reference to the periph before we create the physical
 	 * path alias so it can't go away.
 	 */
-	if (cam_periph_acquire(periph) != CAM_REQ_CMP) {
+	if (cam_periph_acquire(periph) != 0) {
 		xpt_print(periph->path, "%s: lost periph during "
 			  "registration!\n", __func__);
 		cam_periph_lock(periph);
@@ -705,7 +703,7 @@
 	int error;
 
 	periph = (struct cam_periph *)dev->si_drv1;
-	if (cam_periph_acquire(periph) != CAM_REQ_CMP)
+	if (cam_periph_acquire(periph) != 0)
 		return (ENXIO);
 
 	cam_periph_lock(periph);
Index: head/sys/cam/scsi/scsi_pt.c
===================================================================
--- head/sys/cam/scsi/scsi_pt.c
+++ head/sys/cam/scsi/scsi_pt.c
@@ -142,7 +142,7 @@
 	int error = 0;
 
 	periph = (struct cam_periph *)dev->si_drv1;
-	if (cam_periph_acquire(periph) != CAM_REQ_CMP)
+	if (cam_periph_acquire(periph) != 0)
 		return (ENXIO);	
 
 	softc = (struct pt_softc *)periph->softc;
Index: head/sys/cam/scsi/scsi_sa.c
===================================================================
--- head/sys/cam/scsi/scsi_sa.c
+++ head/sys/cam/scsi/scsi_sa.c
@@ -657,7 +657,7 @@
 	int error;
 
 	periph = (struct cam_periph *)dev->si_drv1;
-	if (cam_periph_acquire(periph) != CAM_REQ_CMP) {
+	if (cam_periph_acquire(periph) != 0) {
 		return (ENXIO);
 	}
 
@@ -2495,7 +2495,7 @@
 	 * instances for it.  We'll release this reference once the devfs
 	 * instances have been freed.
 	 */
-	if (cam_periph_acquire(periph) != CAM_REQ_CMP) {
+	if (cam_periph_acquire(periph) != 0) {
 		xpt_print(periph->path, "%s: lost periph during "
 			  "registration!\n", __func__);
 		cam_periph_lock(periph);
Index: head/sys/cam/scsi/scsi_sg.c
===================================================================
--- head/sys/cam/scsi/scsi_sg.c
+++ head/sys/cam/scsi/scsi_sg.c
@@ -353,7 +353,7 @@
 	 * instance for it.  We'll release this reference once the devfs
 	 * instance has been freed.
 	 */
-	if (cam_periph_acquire(periph) != CAM_REQ_CMP) {
+	if (cam_periph_acquire(periph) != 0) {
 		xpt_print(periph->path, "%s: lost periph during "
 			  "registration!\n", __func__);
 		cam_periph_lock(periph);
@@ -439,7 +439,7 @@
 	int error = 0;
 
 	periph = (struct cam_periph *)dev->si_drv1;
-	if (cam_periph_acquire(periph) != CAM_REQ_CMP)
+	if (cam_periph_acquire(periph) != 0)
 		return (ENXIO);
 
 	/*
Index: head/sys/cam/scsi/scsi_xpt.c
===================================================================
--- head/sys/cam/scsi/scsi_xpt.c
+++ head/sys/cam/scsi/scsi_xpt.c
@@ -657,7 +657,6 @@
 proberegister(struct cam_periph *periph, void *arg)
 {
 	union ccb *request_ccb;	/* CCB representing the probe request */
-	cam_status status;
 	probe_softc *softc;
 
 	request_ccb = (union ccb *)arg;
@@ -681,10 +680,9 @@
 	periph->softc = softc;
 	softc->periph = periph;
 	softc->action = PROBE_INVALID;
-	status = cam_periph_acquire(periph);
-	if (status != CAM_REQ_CMP) {
-		return (status);
-	}
+	if (cam_periph_acquire(periph) != 0)
+		return (CAM_REQ_CMP_ERR);
+
 	CAM_DEBUG(periph->path, CAM_DEBUG_PROBE, ("Probe started\n"));
 	scsi_devise_transport(periph->path);