Add framework for raid 4 & 5 so that we can work in tree.

4 files changed, 659 insertions, 3 deletions

diff --git a/sys/conf/files b/sys/conf/files
index 88b454b0d61..e3eeea9aee7 100644
--- a/sys/conf/files
+++ b/sys/conf/files
@@ -1,4 +1,4 @@
-#	$OpenBSD: files,v 1.463 2009/06/06 03:45:08 oga Exp $
+#	$OpenBSD: files,v 1.464 2009/06/10 03:24:02 marco Exp $
 #	$NetBSD: files,v 1.87 1996/05/19 17:17:50 jonathan Exp $
 
 #	@(#)files.newconf	7.5 (Berkeley) 5/10/93
@@ -455,6 +455,7 @@ attach	softraid at root
 file	dev/softraid.c			softraid	needs-flag
 file	dev/softraid_raid0.c		softraid
 file	dev/softraid_raid1.c		softraid
+file	dev/softraid_raidp.c		softraid
 file	dev/softraid_crypto.c		softraid & crypto
 file	dev/softraid_aoe.c		softraid & ether & aoe
 
diff --git a/sys/dev/softraid.c b/sys/dev/softraid.c
index 18dc1eb46dc..f5c70d03265 100644
--- a/sys/dev/softraid.c
+++ b/sys/dev/softraid.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: softraid.c,v 1.145 2009/06/03 21:04:36 marco Exp $ */
+/* $OpenBSD: softraid.c,v 1.146 2009/06/10 03:24:02 marco Exp $ */
 /*
  * Copyright (c) 2007 Marco Peereboom <marco@peereboom.us>
  * Copyright (c) 2008 Chris Kuethe <ckuethe@openbsd.org>
@@ -1948,6 +1948,7 @@ sr_ioctl_setstate(struct sr_softc *sc, struct bioc_setstate *bs)
 	if (sr_meta_save(sd, SR_META_DIRTY)) {
 		printf("%s: could not save metadata to %s\n",
 		    DEVNAME(sc), devname);
+		open = 1;
 		goto done;
 	}
 
@@ -2054,6 +2055,25 @@ sr_ioctl_createraid(struct sr_softc *sc, struct bioc_createraid *bc, int user)
 			strlcpy(sd->sd_name, "RAID 1", sizeof(sd->sd_name));
 			vol_size = ch_entry->src_meta.scmi.scm_coerced_size;
 			break;
+#ifdef not_yet
+		case 4:
+		case 5:
+			if (no_chunk < 3)
+				goto unwind;
+			id ((bc->bc_level == 4)
+				strlcpy(sd->sd_name, "RAID 4", sizeof(sd->sd_name));
+			else
+				strlcpy(sd->sd_name, "RAID 5", sizeof(sd->sd_name));
+			/*
+			 * XXX add variable strip size later even though
+			 * MAXPHYS is really the clever value, users like
+			 * to tinker with that type of stuff
+			 */
+			strip_size = MAXPHYS;
+			vol_size =
+			    ch_entry->src_meta.scmi.scm_coerced_size * (no_chunk - 1);
+			break;
+#endif /* not_yet */
 #ifdef AOE
 #ifdef not_yet
 		case 'A':
@@ -2439,6 +2459,14 @@ sr_discipline_init(struct sr_discipline *sd, int level)
 	case 1:
 		sr_raid1_discipline_init(sd);
 		break;
+	case 4:
+	case 5:
+		if (level == 4)
+			sd->sd_type = SR_MD_RAID4;
+		else
+			sd->sd_type = SR_MD_RAID5;
+		sr_raidp_discipline_init(sd);
+		break;
 #ifdef AOE
 	/* AOE target. */
 	case 'A':
diff --git a/sys/dev/softraid_raidp.c b/sys/dev/softraid_raidp.c
new file mode 100644
index 00000000000..28460c7b23e
--- /dev/null
+++ b/sys/dev/softraid_raidp.c
@@ -0,0 +1,618 @@
+/* $OpenBSD: softraid_raidp.c,v 1.1 2009/06/10 03:24:02 marco Exp $ */
+/*
+ * Copyright (c) 2009 Marco Peereboom <marco@peereboom.us>
+ * Copyright (c) 2009 Jordan Hargrave <jordan@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "bio.h"
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/buf.h>
+#include <sys/device.h>
+#include <sys/ioctl.h>
+#include <sys/proc.h>
+#include <sys/malloc.h>
+#include <sys/kernel.h>
+#include <sys/disk.h>
+#include <sys/rwlock.h>
+#include <sys/queue.h>
+#include <sys/fcntl.h>
+#include <sys/disklabel.h>
+#include <sys/mount.h>
+#include <sys/sensors.h>
+#include <sys/stat.h>
+#include <sys/conf.h>
+#include <sys/uio.h>
+
+#include <scsi/scsi_all.h>
+#include <scsi/scsiconf.h>
+#include <scsi/scsi_disk.h>
+
+#include <dev/softraidvar.h>
+#include <dev/rndvar.h>
+
+/* RAID P functions. */
+int	sr_raidp_alloc_resources(struct sr_discipline *);
+int	sr_raidp_free_resources(struct sr_discipline *);
+int	sr_raidp_rw(struct sr_workunit *);
+void	sr_raidp_intr(struct buf *);
+void	sr_raidp_recreate_wu(struct sr_workunit *);
+void	sr_raidp_set_chunk_state(struct sr_discipline *, int, int);
+void	sr_raidp_set_vol_state(struct sr_discipline *);
+
+/* Discipline initialisation. */
+void
+sr_raidp_discipline_init(struct sr_discipline *sd)
+{
+
+	/* Fill out discipline members. */
+	sd->sd_max_ccb_per_wu = sd->sd_meta->ssdi.ssd_chunk_no;
+	sd->sd_max_wu = SR_RAIDP_NOWU;
+	sd->sd_rebuild = 1;
+
+	/* Setup discipline pointers. */
+	sd->sd_alloc_resources = sr_raidp_alloc_resources;
+	sd->sd_free_resources = sr_raidp_free_resources;
+	sd->sd_start_discipline = NULL;
+	sd->sd_scsi_inquiry = sr_raid_inquiry;
+	sd->sd_scsi_read_cap = sr_raid_read_cap;
+	sd->sd_scsi_tur = sr_raid_tur;
+	sd->sd_scsi_req_sense = sr_raid_request_sense;
+	sd->sd_scsi_start_stop = sr_raid_start_stop;
+	sd->sd_scsi_sync = sr_raid_sync;
+	sd->sd_scsi_rw = sr_raidp_rw;
+	sd->sd_set_chunk_state = sr_raidp_set_chunk_state;
+	sd->sd_set_vol_state = sr_raidp_set_vol_state;
+}
+
+int
+sr_raidp_alloc_resources(struct sr_discipline *sd)
+{
+	int			rv = EINVAL;
+
+	if (!sd)
+		return (rv);
+
+	DNPRINTF(SR_D_DIS, "%s: sr_raidp_alloc_resources\n",
+	    DEVNAME(sd->sd_sc));
+
+	if (sr_wu_alloc(sd))
+		goto bad;
+	if (sr_ccb_alloc(sd))
+		goto bad;
+
+	rv = 0;
+bad:
+	return (rv);
+}
+
+int
+sr_raidp_free_resources(struct sr_discipline *sd)
+{
+	int			rv = EINVAL;
+
+	if (!sd)
+		return (rv);
+
+	DNPRINTF(SR_D_DIS, "%s: sr_raidp_free_resources\n",
+	    DEVNAME(sd->sd_sc));
+
+	sr_wu_free(sd);
+	sr_ccb_free(sd);
+
+	rv = 0;
+	return (rv);
+}
+
+void
+sr_raidp_set_chunk_state(struct sr_discipline *sd, int c, int new_state)
+{
+	int			old_state, s;
+
+	DNPRINTF(SR_D_STATE, "%s: %s: %s: sr_raid_set_chunk_state %d -> %d\n",
+	    DEVNAME(sd->sd_sc), sd->sd_meta->ssd_devname,
+	    sd->sd_vol.sv_chunks[c]->src_meta.scmi.scm_devname, c, new_state);
+
+	/* ok to go to splbio since this only happens in error path */
+	s = splbio();
+	old_state = sd->sd_vol.sv_chunks[c]->src_meta.scm_status;
+
+	/* multiple IOs to the same chunk that fail will come through here */
+	if (old_state == new_state)
+		goto done;
+
+	switch (old_state) {
+	case BIOC_SDONLINE:
+		switch (new_state) {
+		case BIOC_SDOFFLINE:
+			break;
+		case BIOC_SDSCRUB:
+			break;
+		default:
+			goto die;
+		}
+		break;
+
+	case BIOC_SDOFFLINE:
+		if (new_state == BIOC_SDREBUILD) {
+			;
+		} else
+			goto die;
+		break;
+
+	case BIOC_SDSCRUB:
+		if (new_state == BIOC_SDONLINE) {
+			;
+		} else
+			goto die;
+		break;
+
+	case BIOC_SDREBUILD:
+		if (new_state == BIOC_SDONLINE) {
+			;
+		} else
+			goto die;
+		break;
+
+	case BIOC_SDHOTSPARE:
+		if (new_state == BIOC_SDREBUILD) {
+			;
+		} else
+			goto die;
+		break;
+
+	default:
+die:
+		splx(s); /* XXX */
+		panic("%s: %s: %s: invalid chunk state transition "
+		    "%d -> %d\n", DEVNAME(sd->sd_sc),
+		    sd->sd_meta->ssd_devname,
+		    sd->sd_vol.sv_chunks[c]->src_meta.scmi.scm_devname,
+		    old_state, new_state);
+		/* NOTREACHED */
+	}
+
+	sd->sd_vol.sv_chunks[c]->src_meta.scm_status = new_state;
+	sd->sd_set_vol_state(sd);
+
+	sd->sd_must_flush = 1;
+	workq_add_task(NULL, 0, sr_meta_save_callback, sd, NULL);
+done:
+	splx(s);
+}
+
+void
+sr_raidp_set_vol_state(struct sr_discipline *sd)
+{
+	int			states[SR_MAX_STATES];
+	int			new_state, i, s, nd;
+	int			old_state = sd->sd_vol_status;
+
+	DNPRINTF(SR_D_STATE, "%s: %s: sr_raid_set_vol_state\n",
+	    DEVNAME(sd->sd_sc), sd->sd_meta->ssd_devname);
+
+	nd = sd->sd_meta->ssdi.ssd_chunk_no;
+
+	for (i = 0; i < SR_MAX_STATES; i++)
+		states[i] = 0;
+
+	for (i = 0; i < nd; i++) {
+		s = sd->sd_vol.sv_chunks[i]->src_meta.scm_status;
+		if (s >= SR_MAX_STATES)
+			panic("%s: %s: %s: invalid chunk state",
+			    DEVNAME(sd->sd_sc),
+			    sd->sd_meta->ssd_devname,
+			    sd->sd_vol.sv_chunks[i]->src_meta.scmi.scm_devname);
+		states[s]++;
+	}
+
+	if (states[BIOC_SDONLINE] == nd)
+		new_state = BIOC_SVONLINE;
+	else if (states[BIOC_SDONLINE] == 0)
+		new_state = BIOC_SVOFFLINE;
+	else if (states[BIOC_SDSCRUB] != 0)
+		new_state = BIOC_SVSCRUB;
+	else if (states[BIOC_SDREBUILD] != 0)
+		new_state = BIOC_SVREBUILD;
+	else if (states[BIOC_SDOFFLINE] != 0)
+		new_state = BIOC_SVDEGRADED;
+	else {
+		printf("old_state = %d, ", old_state);
+		for (i = 0; i < nd; i++)
+			printf("%d = %d, ", i,
+			    sd->sd_vol.sv_chunks[i]->src_meta.scm_status);
+		panic("invalid new_state");
+	}
+
+	DNPRINTF(SR_D_STATE, "%s: %s: sr_raid_set_vol_state %d -> %d\n",
+	    DEVNAME(sd->sd_sc), sd->sd_meta->ssd_devname,
+	    old_state, new_state);
+
+	switch (old_state) {
+	case BIOC_SVONLINE:
+		switch (new_state) {
+		case BIOC_SVONLINE: /* can go to same state */
+		case BIOC_SVOFFLINE:
+		case BIOC_SVDEGRADED:
+		case BIOC_SVREBUILD: /* happens on boot */
+			break;
+		default:
+			goto die;
+		}
+		break;
+
+	case BIOC_SVOFFLINE:
+		/* XXX this might be a little too much */
+		goto die;
+
+	case BIOC_SVSCRUB:
+		switch (new_state) {
+		case BIOC_SVONLINE:
+		case BIOC_SVOFFLINE:
+		case BIOC_SVDEGRADED:
+		case BIOC_SVSCRUB: /* can go to same state */
+			break;
+		default:
+			goto die;
+		}
+		break;
+
+	case BIOC_SVBUILDING:
+		switch (new_state) {
+		case BIOC_SVONLINE:
+		case BIOC_SVOFFLINE:
+		case BIOC_SVBUILDING: /* can go to the same state */
+			break;
+		default:
+			goto die;
+		}
+		break;
+
+	case BIOC_SVREBUILD:
+		switch (new_state) {
+		case BIOC_SVONLINE:
+		case BIOC_SVOFFLINE:
+		case BIOC_SVDEGRADED:
+		case BIOC_SVREBUILD: /* can go to the same state */
+			break;
+		default:
+			goto die;
+		}
+		break;
+
+	case BIOC_SVDEGRADED:
+		switch (new_state) {
+		case BIOC_SVOFFLINE:
+		case BIOC_SVREBUILD:
+		case BIOC_SVDEGRADED: /* can go to the same state */
+			break;
+		default:
+			goto die;
+		}
+		break;
+
+	default:
+die:
+		panic("%s: %s: invalid volume state transition "
+		    "%d -> %d\n", DEVNAME(sd->sd_sc),
+		    sd->sd_meta->ssd_devname,
+		    old_state, new_state);
+		/* NOTREACHED */
+	}
+
+	sd->sd_vol_status = new_state;
+}
+
+int
+sr_raidp_rw(struct sr_workunit *wu)
+{
+#if 0
+	struct sr_discipline	*sd = wu->swu_dis;
+	struct scsi_xfer	*xs = wu->swu_xs;
+#endif
+	int			s;
+	daddr64_t		blk;
+#if 0
+	struct sr_ccb		*ccb;
+	struct sr_chunk		*scp;
+	int			ios, x, i, s, rt;
+#endif
+	/* blk and scsi error will be handled by sr_validate_io */
+	if (sr_validate_io(wu, &blk, "sr_raidp_rw"))
+		goto bad;
+
+	/* calculate physical block */
+	blk += SR_META_SIZE + SR_META_OFFSET;
+
+	/* XXX replace this with raid 4 & 5! */
+	goto bad;
+#if 0
+	if (xs->flags & SCSI_DATA_IN)
+		ios = 1;
+	else
+		ios = sd->sd_meta->ssdi.ssd_chunk_no;
+	wu->swu_io_count = ios;
+
+	for (i = 0; i < ios; i++) {
+		ccb = sr_ccb_get(sd);
+		if (!ccb) {
+			/* should never happen but handle more gracefully */
+			printf("%s: %s: too many ccbs queued\n",
+			    DEVNAME(sd->sd_sc),
+			    sd->sd_meta->ssd_devname);
+			goto bad;
+		}
+
+		if (xs->flags & SCSI_POLL) {
+			ccb->ccb_buf.b_flags = 0;
+			ccb->ccb_buf.b_iodone = NULL;
+		} else {
+			ccb->ccb_buf.b_flags = B_CALL;
+			ccb->ccb_buf.b_iodone = sr_raidp_intr;
+		}
+
+		ccb->ccb_buf.b_flags |= B_PHYS;
+		ccb->ccb_buf.b_blkno = blk;
+		ccb->ccb_buf.b_bcount = xs->datalen;
+		ccb->ccb_buf.b_bufsize = xs->datalen;
+		ccb->ccb_buf.b_resid = xs->datalen;
+		ccb->ccb_buf.b_data = xs->data;
+		ccb->ccb_buf.b_error = 0;
+		ccb->ccb_buf.b_proc = curproc;
+		ccb->ccb_wu = wu;
+
+		if (xs->flags & SCSI_DATA_IN) {
+			rt = 0;
+ragain:
+			/* interleave reads */
+			x = sd->mds.mdd_raidp.sr1_counter++ %
+			    sd->sd_meta->ssdi.ssd_chunk_no;
+			scp = sd->sd_vol.sv_chunks[x];
+			switch (scp->src_meta.scm_status) {
+			case BIOC_SDONLINE:
+			case BIOC_SDSCRUB:
+				ccb->ccb_buf.b_flags |= B_READ;
+				break;
+
+			case BIOC_SDOFFLINE:
+			case BIOC_SDREBUILD:
+			case BIOC_SDHOTSPARE:
+				if (rt++ < sd->sd_meta->ssdi.ssd_chunk_no)
+					goto ragain;
+
+				/* FALLTHROUGH */
+			default:
+				/* volume offline */
+				printf("%s: is offline, can't read\n",
+				    DEVNAME(sd->sd_sc));
+				sr_ccb_put(ccb);
+				goto bad;
+			}
+		} else {
+			/* writes go on all working disks */
+			x = i;
+			scp = sd->sd_vol.sv_chunks[x];
+			switch (scp->src_meta.scm_status) {
+			case BIOC_SDONLINE:
+			case BIOC_SDSCRUB:
+			case BIOC_SDREBUILD:
+				ccb->ccb_buf.b_flags |= B_WRITE;
+				break;
+
+			case BIOC_SDHOTSPARE: /* should never happen */
+			case BIOC_SDOFFLINE:
+				wu->swu_io_count--;
+				sr_ccb_put(ccb);
+				continue;
+
+			default:
+				goto bad;
+			}
+
+		}
+		ccb->ccb_target = x;
+		ccb->ccb_buf.b_dev = sd->sd_vol.sv_chunks[x]->src_dev_mm;
+		ccb->ccb_buf.b_vp = NULL;
+
+		LIST_INIT(&ccb->ccb_buf.b_dep);
+
+		TAILQ_INSERT_TAIL(&wu->swu_ccb, ccb, ccb_link);
+
+		DNPRINTF(SR_D_DIS, "%s: %s: sr_raidp: b_bcount: %d "
+		    "b_blkno: %x b_flags 0x%0x b_data %p\n",
+		    DEVNAME(sd->sd_sc), sd->sd_meta->ssd_devname,
+		    ccb->ccb_buf.b_bcount, ccb->ccb_buf.b_blkno,
+		    ccb->ccb_buf.b_flags, ccb->ccb_buf.b_data);
+	}
+#endif
+	s = splbio();
+
+	/* rebuild io, let rebuild routine deal with it */
+	if (wu->swu_flags & SR_WUF_REBUILD)
+		goto queued;
+
+	/* current io failed, restart */
+	if (wu->swu_state == SR_WU_RESTART)
+		goto start;
+
+	/* deferred io failed, don't restart */
+	if (wu->swu_state == SR_WU_REQUEUE)
+		goto queued;
+
+	if (sr_check_io_collision(wu))
+		goto queued;
+
+start:
+	sr_raid_startwu(wu);
+queued:
+	splx(s);
+	return (0);
+bad:
+	/* wu is unwound by sr_wu_put */
+	return (1);
+}
+
+void
+sr_raidp_intr(struct buf *bp)
+{
+	struct sr_ccb		*ccb = (struct sr_ccb *)bp;
+	struct sr_workunit	*wu = ccb->ccb_wu, *wup;
+	struct sr_discipline	*sd = wu->swu_dis;
+	struct scsi_xfer	*xs = wu->swu_xs;
+	struct sr_softc		*sc = sd->sd_sc;
+	int			s, pend;
+
+	DNPRINTF(SR_D_INTR, "%s: sr_intr bp %x xs %x\n",
+	    DEVNAME(sc), bp, xs);
+
+	DNPRINTF(SR_D_INTR, "%s: sr_intr: b_bcount: %d b_resid: %d"
+	    " b_flags: 0x%0x block: %lld target: %d\n", DEVNAME(sc),
+	    ccb->ccb_buf.b_bcount, ccb->ccb_buf.b_resid, ccb->ccb_buf.b_flags,
+	    ccb->ccb_buf.b_blkno, ccb->ccb_target);
+
+	s = splbio();
+
+	if (ccb->ccb_buf.b_flags & B_ERROR) {
+		DNPRINTF(SR_D_INTR, "%s: i/o error on block %lld target: %d\n",
+		    DEVNAME(sc), ccb->ccb_buf.b_blkno, ccb->ccb_target);
+		wu->swu_ios_failed++;
+		ccb->ccb_state = SR_CCB_FAILED;
+		if (ccb->ccb_target != -1)
+			sd->sd_set_chunk_state(sd, ccb->ccb_target,
+			    BIOC_SDOFFLINE);
+		else
+			panic("%s: invalid target on wu: %p", DEVNAME(sc), wu);
+	} else {
+		ccb->ccb_state = SR_CCB_OK;
+		wu->swu_ios_succeeded++;
+	}
+	wu->swu_ios_complete++;
+
+	DNPRINTF(SR_D_INTR, "%s: sr_intr: comp: %d count: %d failed: %d\n",
+	    DEVNAME(sc), wu->swu_ios_complete, wu->swu_io_count,
+	    wu->swu_ios_failed);
+
+	if (wu->swu_ios_complete >= wu->swu_io_count) {
+		/* if all ios failed, retry reads and give up on writes */
+		if (wu->swu_ios_failed == wu->swu_ios_complete) {
+			if (xs->flags & SCSI_DATA_IN) {
+				printf("%s: retrying read on block %lld\n",
+				    DEVNAME(sc), ccb->ccb_buf.b_blkno);
+				sr_ccb_put(ccb);
+				TAILQ_INIT(&wu->swu_ccb);
+				wu->swu_state = SR_WU_RESTART;
+				if (sd->sd_scsi_rw(wu))
+					goto bad;
+				else
+					goto retry;
+			} else {
+				printf("%s: permanently fail write on block "
+				    "%lld\n", DEVNAME(sc),
+				    ccb->ccb_buf.b_blkno);
+				xs->error = XS_DRIVER_STUFFUP;
+				goto bad;
+			}
+		}
+
+		xs->error = XS_NOERROR;
+		xs->resid = 0;
+		xs->flags |= ITSDONE;
+
+		pend = 0;
+		TAILQ_FOREACH(wup, &sd->sd_wu_pendq, swu_link) {
+			if (wu == wup) {
+				/* wu on pendq, remove */
+				TAILQ_REMOVE(&sd->sd_wu_pendq, wu, swu_link);
+				pend = 1;
+
+				if (wu->swu_collider) {
+					if (wu->swu_ios_failed)
+						/* toss all ccbs and recreate */
+						sr_raidp_recreate_wu(wu->swu_collider);
+
+					/* restart deferred wu */
+					wu->swu_collider->swu_state =
+					    SR_WU_INPROGRESS;
+					TAILQ_REMOVE(&sd->sd_wu_defq,
+					    wu->swu_collider, swu_link);
+					sr_raid_startwu(wu->swu_collider);
+				}
+				break;
+			}
+		}
+
+		if (!pend)
+			printf("%s: wu: %p not on pending queue\n",
+			    DEVNAME(sc), wu);
+
+		if (wu->swu_flags & SR_WUF_REBUILD) {
+			if (wu->swu_xs->flags & SCSI_DATA_OUT) {
+				wu->swu_flags |= SR_WUF_REBUILDIOCOMP;
+				wakeup(wu);
+			}
+		} else {
+			/* do not change the order of these 2 functions */
+			sr_wu_put(wu);
+			scsi_done(xs);
+		}
+
+		if (sd->sd_sync && sd->sd_wu_pending == 0)
+			wakeup(sd);
+	}
+
+retry:
+	splx(s);
+	return;
+bad:
+	xs->error = XS_DRIVER_STUFFUP;
+	xs->flags |= ITSDONE;
+	if (wu->swu_flags & SR_WUF_REBUILD) {
+		wu->swu_flags |= SR_WUF_REBUILDIOCOMP;
+		wakeup(wu);
+	} else {
+		/* do not change the order of these 2 functions */
+		sr_wu_put(wu);
+		scsi_done(xs);
+	}
+
+	splx(s);
+}
+
+void
+sr_raidp_recreate_wu(struct sr_workunit *wu)
+{
+	struct sr_discipline	*sd = wu->swu_dis;
+	struct sr_workunit	*wup = wu;
+	struct sr_ccb		*ccb;
+
+	do {
+		DNPRINTF(SR_D_INTR, "%s: sr_raidp_recreate_wu: %p\n", wup);
+
+		/* toss all ccbs */
+		while ((ccb = TAILQ_FIRST(&wup->swu_ccb)) != NULL) {
+			TAILQ_REMOVE(&wup->swu_ccb, ccb, ccb_link);
+			sr_ccb_put(ccb);
+		}
+		TAILQ_INIT(&wup->swu_ccb);
+
+		/* recreate ccbs */
+		wup->swu_state = SR_WU_REQUEUE;
+		if (sd->sd_scsi_rw(wup))
+			panic("could not requeue io");
+
+		wup = wup->swu_collider;
+	} while (wup);
+}
diff --git a/sys/dev/softraidvar.h b/sys/dev/softraidvar.h
index 7b9156b0d36..c342ac17e12 100644
--- a/sys/dev/softraidvar.h
+++ b/sys/dev/softraidvar.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: softraidvar.h,v 1.71 2009/06/03 21:04:36 marco Exp $ */
+/* $OpenBSD: softraidvar.h,v 1.72 2009/06/10 03:24:02 marco Exp $ */
 /*
  * Copyright (c) 2006 Marco Peereboom <marco@peereboom.us>
  * Copyright (c) 2008 Chris Kuethe <ckuethe@openbsd.org>
@@ -295,6 +295,12 @@ struct sr_raid1 {
 	u_int32_t		sr1_counter;
 };
 
+/* RAID 4 */
+#define SR_RAIDP_NOWU		16
+struct sr_raidp {
+	int32_t			srp_strip_bits;
+};
+
 /* CRYPTO */
 #define SR_CRYPTO_NOWU		16
 struct sr_crypto {
@@ -366,6 +372,7 @@ struct sr_discipline {
 #define	SR_MD_CRYPTO		4
 #define	SR_MD_AOE_INIT		5
 #define	SR_MD_AOE_TARG		6
+#define	SR_MD_RAID4		7
 	char			sd_name[10];	/* human readable dis name */
 	u_int8_t		sd_scsibus;	/* scsibus discipline uses */
 	struct scsi_link	sd_link;	/* link to midlayer */
@@ -373,6 +380,7 @@ struct sr_discipline {
 	union {
 	    struct sr_raid0	mdd_raid0;
 	    struct sr_raid1	mdd_raid1;
+	    struct sr_raidp	mdd_raidp;
 	    struct sr_crypto	mdd_crypto;
 #ifdef AOE
 	    struct sr_aoe	mdd_aoe;
@@ -492,6 +500,7 @@ void			sr_raid_startwu(struct sr_workunit *);
 /* Discipline specific initialisation. */
 void			sr_raid0_discipline_init(struct sr_discipline *);
 void			sr_raid1_discipline_init(struct sr_discipline *);
+void			sr_raidp_discipline_init(struct sr_discipline *);
 void			sr_crypto_discipline_init(struct sr_discipline *);
 void			sr_aoe_discipline_init(struct sr_discipline *);
 void			sr_aoe_server_discipline_init(struct sr_discipline *);