/* $OpenBSD: softraid_raid0.c,v 1.1 2008/01/19 23:53:53 marco Exp $ */
/*
 * Copyright (c) 2008 Marco Peereboom <marco@peereboom.us>
 *
 * 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 0 functions */
int
sr_raid0_alloc_resources(struct sr_discipline *sd)
{
	int			rv = EINVAL;

	if (!sd)
		return (rv);

	DNPRINTF(SR_D_DIS, "%s: sr_raid0_alloc_resources\n",
	    DEVNAME(sd->sd_sc));

	if (sr_alloc_wu(sd))
		goto bad;
	if (sr_alloc_ccb(sd))
		goto bad;

	/* setup runtime values */
	sd->mds.mdd_raid0.sr0_stripbits =
	    sr_validate_stripsize(sd->sd_vol.sv_meta.svm_strip_size);
	if (sd->mds.mdd_raid0.sr0_stripbits == -1)
		goto bad;

	rv = 0;
bad:
	return (rv);
}

int
sr_raid0_free_resources(struct sr_discipline *sd)
{
	int			rv = EINVAL;

	if (!sd)
		return (rv);

	DNPRINTF(SR_D_DIS, "%s: sr_raid0_free_resources\n",
	    DEVNAME(sd->sd_sc));

	sr_free_wu(sd);
	sr_free_ccb(sd);

	if (sd->sd_meta)
		free(sd->sd_meta, M_DEVBUF);

	rv = 0;
	return (rv);
}

int
sr_raid0_rw(struct sr_workunit *wu)
{
	struct sr_discipline	*sd = wu->swu_dis;
	struct scsi_xfer	*xs = wu->swu_xs;
	struct sr_workunit	*wup;
	int			s;
	daddr64_t		blk;

	DNPRINTF(SR_D_DIS, "%s: sr_raid0_rw 0x%02x\n", DEVNAME(sd->sd_sc),
	    xs->cmd->opcode);

	/* XXX don't do io yet */
	goto bad;

	if (sd->sd_vol.sv_meta.svm_status == BIOC_SVOFFLINE) {
		DNPRINTF(SR_D_DIS, "%s: sr_raid0_rw device offline\n",
		    DEVNAME(sd->sd_sc));
		goto bad;
	}

	if (xs->datalen == 0) {
		printf("%s: %s: illegal block count\n",
		    DEVNAME(sd->sd_sc), sd->sd_vol.sv_meta.svm_devname);
		goto bad;
	}

	if (xs->cmdlen == 10)
		blk = _4btol(((struct scsi_rw_big *)xs->cmd)->addr);
	else if (xs->cmdlen == 6)
		blk = _3btol(((struct scsi_rw *)xs->cmd)->addr);
	else {
		printf("%s: %s: illegal cmdlen\n", DEVNAME(sd->sd_sc),
		    sd->sd_vol.sv_meta.svm_devname);
		goto bad;
	}

	wu->swu_blk_start = blk;
	wu->swu_blk_end = blk + (xs->datalen >> 9) - 1;

	if (wu->swu_blk_end > sd->sd_vol.sv_meta.svm_size) {
		DNPRINTF(SR_D_DIS, "%s: sr_raid0_rw out of bounds start: %lld "
		    "end: %lld length: %d\n", wu->swu_blk_start,
		    wu->swu_blk_end, xs->datalen);

		sd->sd_scsi_sense.error_code = SSD_ERRCODE_CURRENT |
		    SSD_ERRCODE_VALID;
		sd->sd_scsi_sense.flags = SKEY_ILLEGAL_REQUEST;
		sd->sd_scsi_sense.add_sense_code = 0x21;
		sd->sd_scsi_sense.add_sense_code_qual = 0x00;
		sd->sd_scsi_sense.extra_len = 4;
		goto bad;
	}

	/* calculate physical block */
	blk += SR_META_SIZE + SR_META_OFFSET;
	s = splbio();

	/* generate ios */

	/* walk queue backwards and fill in collider if we have one */
	TAILQ_FOREACH_REVERSE(wup, &sd->sd_wu_pendq, sr_wu_list, swu_link) {
		if (wu->swu_blk_end < wup->swu_blk_start ||
		    wup->swu_blk_end < wu->swu_blk_start)
			continue;

		/* we have an LBA collision, defer wu */
		wu->swu_state = SR_WU_DEFERRED;
		if (wup->swu_collider)
			/* wu is on deferred queue, append to last wu */
			while (wup->swu_collider)
				wup = wup->swu_collider;

		wup->swu_collider = wu;
		TAILQ_INSERT_TAIL(&sd->sd_wu_defq, wu, swu_link);
		sd->sd_wu_collisions++;
		goto queued;
	}

/* start: */
	sr_raid_startwu(wu);
queued:
	splx(s);
	return (0);
bad:
	/* wu is unwound by sr_put_wu */
	return (1);
}

void
sr_raid0_intr(struct buf *bp)
{
	struct sr_ccb		*ccb = (struct sr_ccb *)bp;
	struct sr_workunit	*wu = ccb->ccb_wu;
	struct sr_discipline	*sd = wu->swu_dis;
	struct scsi_xfer	*xs = wu->swu_xs;
	struct sr_softc		*sc = sd->sd_sc;
	int			s;

	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);

/* bad: */
	xs->error = XS_DRIVER_STUFFUP;
	xs->flags |= ITSDONE;
	sr_put_wu(wu);
	scsi_done(xs);
	splx(s);
}