geom_vinum_raid5.h revision 139778
1139778Simp/*-
2130389Sle * Copyright (c) 2004 Lukas Ertl
3130389Sle * All rights reserved.
4130389Sle *
5130389Sle * Redistribution and use in source and binary forms, with or without
6130389Sle * modification, are permitted provided that the following conditions
7130389Sle * are met:
8130389Sle * 1. Redistributions of source code must retain the above copyright
9130389Sle *    notice, this list of conditions and the following disclaimer.
10130389Sle * 2. Redistributions in binary form must reproduce the above copyright
11130389Sle *    notice, this list of conditions and the following disclaimer in the
12130389Sle *    documentation and/or other materials provided with the distribution.
13130389Sle *
14130389Sle * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15130389Sle * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16130389Sle * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17130389Sle * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18130389Sle * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19130389Sle * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20130389Sle * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21130389Sle * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22130389Sle * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23130389Sle * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24130389Sle * SUCH DAMAGE.
25130389Sle *
26130389Sle * $FreeBSD: head/sys/geom/vinum/geom_vinum_raid5.h 139778 2005-01-06 18:27:30Z imp $
27130389Sle */
28130389Sle
29130389Sle#ifndef _GEOM_VINUM_RAID5_H_
30130389Sle#define	_GEOM_VINUM_RAID5_H_
31130389Sle
32130389Sle/*
33130389Sle * A single RAID5 request usually needs more than one I/O transaction,
34130389Sle * depending on the state of the associated subdisks and the direction of the
35135426Sle * transaction (read or write).
36130389Sle */
37130389Sle
38135426Sle#define	GV_ENQUEUE(bp, cbp, pbp)				\
39135426Sle	do { 							\
40135426Sle		if (bp->bio_driver1 == NULL) {			\
41135426Sle			bp->bio_driver1 = cbp;			\
42135426Sle		} else {					\
43135426Sle			pbp = bp->bio_driver1;			\
44135426Sle			while (pbp->bio_caller1 != NULL)	\
45135426Sle				pbp = pbp->bio_caller1;		\
46135426Sle			pbp->bio_caller1 = cbp;			\
47135426Sle		}						\
48135426Sle	} while (0);
49130389Sle
50130389Slestruct gv_raid5_packet {
51135426Sle	caddr_t	data;		/* Data buffer of this sub-request- */
52130389Sle	off_t	length;		/* Size of data buffer. */
53130389Sle	off_t	lockbase;	/* Deny access to our plex offset. */
54130389Sle	off_t	offset;		/* The drive offset of the subdisk. */
55130389Sle	int	bufmalloc;	/* Flag if data buffer was malloced. */
56130389Sle	int	active;		/* Count of active subrequests. */
57130389Sle	int	rqcount;	/* Count of subrequests. */
58130389Sle
59130389Sle	struct bio	*bio;	/* Pointer to the original bio. */
60135426Sle	struct bio	*parity;  /* The bio containing the parity data. */
61135426Sle	struct bio	*waiting; /* A bio that need to wait for other bios. */
62130389Sle
63135426Sle	TAILQ_HEAD(,gv_bioq)		bits; /* List of subrequests. */
64135426Sle	TAILQ_ENTRY(gv_raid5_packet)	list; /* Entry in plex's packet list. */
65130389Sle};
66130389Sle
67135426Sleint	gv_stripe_active(struct gv_plex *, struct bio *);
68135426Sleint	gv_build_raid5_req(struct gv_plex *, struct gv_raid5_packet *,
69135426Sle	    struct bio *, caddr_t, off_t, off_t);
70138110Sleint	gv_check_raid5(struct gv_plex *, struct gv_raid5_packet *,
71138110Sle	    struct bio *, caddr_t, off_t, off_t);
72135966Sleint	gv_rebuild_raid5(struct gv_plex *, struct gv_raid5_packet *,
73135966Sle	    struct bio *, caddr_t, off_t, off_t);
74130389Slevoid	gv_raid5_worker(void *);
75135426Slevoid	gv_plex_done(struct bio *);
76130389Sle
77130389Sle#endif /* !_GEOM_VINUM_RAID5_H_ */
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