freebsd-skq/sys/geom/vinum/geom_vinum_raid5.h

78 lines
3.0 KiB
C

/*-
* Copyright (c) 2004 Lukas Ertl
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _GEOM_VINUM_RAID5_H_
#define _GEOM_VINUM_RAID5_H_
/*
* A single RAID5 request usually needs more than one I/O transaction,
* depending on the state of the associated subdisks and the direction of the
* transaction (read or write).
*/
#define GV_ENQUEUE(bp, cbp, pbp) \
do { \
if (bp->bio_driver1 == NULL) { \
bp->bio_driver1 = cbp; \
} else { \
pbp = bp->bio_driver1; \
while (pbp->bio_caller1 != NULL) \
pbp = pbp->bio_caller1; \
pbp->bio_caller1 = cbp; \
} \
} while (0);
struct gv_raid5_packet {
caddr_t data; /* Data buffer of this sub-request- */
off_t length; /* Size of data buffer. */
off_t lockbase; /* Deny access to our plex offset. */
off_t offset; /* The drive offset of the subdisk. */
int bufmalloc; /* Flag if data buffer was malloced. */
int active; /* Count of active subrequests. */
int rqcount; /* Count of subrequests. */
struct bio *bio; /* Pointer to the original bio. */
struct bio *parity; /* The bio containing the parity data. */
struct bio *waiting; /* A bio that need to wait for other bios. */
TAILQ_HEAD(,gv_bioq) bits; /* List of subrequests. */
TAILQ_ENTRY(gv_raid5_packet) list; /* Entry in plex's packet list. */
};
int gv_stripe_active(struct gv_plex *, struct bio *);
int gv_build_raid5_req(struct gv_plex *, struct gv_raid5_packet *,
struct bio *, caddr_t, off_t, off_t);
int gv_check_raid5(struct gv_plex *, struct gv_raid5_packet *,
struct bio *, caddr_t, off_t, off_t);
int gv_rebuild_raid5(struct gv_plex *, struct gv_raid5_packet *,
struct bio *, caddr_t, off_t, off_t);
void gv_raid5_worker(void *);
void gv_plex_done(struct bio *);
#endif /* !_GEOM_VINUM_RAID5_H_ */