From 255694f7fcc31bc747caaa62a7db837cdc9899e7 Mon Sep 17 00:00:00 2001 From: le Date: Mon, 15 Nov 2004 13:04:55 +0000 Subject: Move RAID5 offset calculation into a separate function to avoid code duplication. --- sys/geom/vinum/geom_vinum_raid5.c | 106 ++++++++++++++++++++------------------ 1 file changed, 56 insertions(+), 50 deletions(-) (limited to 'sys') diff --git a/sys/geom/vinum/geom_vinum_raid5.c b/sys/geom/vinum/geom_vinum_raid5.c index 9ba02e8..11bb931 100644 --- a/sys/geom/vinum/geom_vinum_raid5.c +++ b/sys/geom/vinum/geom_vinum_raid5.c @@ -44,6 +44,9 @@ __FBSDID("$FreeBSD$"); #include #include +int gv_raid5_offset(struct gv_plex *, off_t, off_t, off_t *, off_t *, + int *, int *); + /* * Check if the stripe that the work packet wants is already being used by * some other work packet. @@ -84,27 +87,12 @@ gv_rebuild_raid5(struct gv_plex *p, struct gv_raid5_packet *wp, struct bio *bp, struct gv_sd *broken, *s; struct gv_bioq *bq; struct bio *cbp, *pbp; - off_t len_left, real_len, real_off, stripeend, stripeoff, stripestart; + off_t real_len, real_off; if (p == NULL || LIST_EMPTY(&p->subdisks)) return (ENXIO); - /* Offset of the start address from the start of the stripe. */ - stripeoff = boff % (p->stripesize * (p->sdcount - 1)); - KASSERT(stripeoff >= 0, ("gv_build_raid5_request: stripeoff < 0")); - - /* The offset of the stripe on this subdisk. */ - stripestart = (boff - stripeoff) / (p->sdcount - 1); - KASSERT(stripestart >= 0, ("gv_build_raid5_request: stripestart < 0")); - - stripeoff %= p->stripesize; - - /* The offset of the request on this subdisk. */ - real_off = stripestart + stripeoff; - - stripeend = stripestart + p->stripesize; - len_left = stripeend - real_off; - KASSERT(len_left >= 0, ("gv_build_raid5_request: len_left < 0")); + gv_raid5_offset(p, boff, bcount, &real_off, &real_len, NULL, NULL); /* Find the right subdisk. */ broken = NULL; @@ -137,12 +125,11 @@ gv_rebuild_raid5(struct gv_plex *p, struct gv_raid5_packet *wp, struct bio *bp, return (ENXIO); } - real_len = (bcount <= len_left) ? bcount : len_left; wp->length = real_len; wp->data = addr; wp->lockbase = real_off; - KASSERT(wp->length >= 0, ("gv_build_raid5_request: wp->length < 0")); + KASSERT(wp->length >= 0, ("gv_rebuild_raid5: wp->length < 0")); /* Read all subdisks. */ LIST_FOREACH(s, &p->subdisks, in_plex) { @@ -198,7 +185,7 @@ gv_build_raid5_req(struct gv_plex *p, struct gv_raid5_packet *wp, struct gv_bioq *bq; struct bio *cbp, *pbp; int i, psdno, sdno, type; - off_t len_left, real_len, real_off, stripeend, stripeoff, stripestart; + off_t real_len, real_off; gp = bp->bio_to->geom; @@ -213,35 +200,7 @@ gv_build_raid5_req(struct gv_plex *p, struct gv_raid5_packet *wp, type = REQ_TYPE_NORMAL; original = parity = broken = NULL; - /* The number of the subdisk containing the parity stripe. */ - psdno = p->sdcount - 1 - ( boff / (p->stripesize * (p->sdcount - 1))) % - p->sdcount; - KASSERT(psdno >= 0, ("gv_build_raid5_request: psdno < 0")); - - /* Offset of the start address from the start of the stripe. */ - stripeoff = boff % (p->stripesize * (p->sdcount - 1)); - KASSERT(stripeoff >= 0, ("gv_build_raid5_request: stripeoff < 0")); - - /* The number of the subdisk where the stripe resides. */ - sdno = stripeoff / p->stripesize; - KASSERT(sdno >= 0, ("gv_build_raid5_request: sdno < 0")); - - /* At or past parity subdisk. */ - if (sdno >= psdno) - sdno++; - - /* The offset of the stripe on this subdisk. */ - stripestart = (boff - stripeoff) / (p->sdcount - 1); - KASSERT(stripestart >= 0, ("gv_build_raid5_request: stripestart < 0")); - - stripeoff %= p->stripesize; - - /* The offset of the request on this subdisk. */ - real_off = stripestart + stripeoff; - - stripeend = stripestart + p->stripesize; - len_left = stripeend - real_off; - KASSERT(len_left >= 0, ("gv_build_raid5_request: len_left < 0")); + gv_raid5_offset(p, boff, bcount, &real_off, &real_len, &sdno, &psdno); /* Find the right subdisks. */ i = 0; @@ -270,7 +229,6 @@ gv_build_raid5_req(struct gv_plex *p, struct gv_raid5_packet *wp, type = REQ_TYPE_NOPARITY; } - real_len = (bcount <= len_left) ? bcount : len_left; wp->length = real_len; wp->data = addr; wp->lockbase = real_off; @@ -481,3 +439,51 @@ gv_build_raid5_req(struct gv_plex *p, struct gv_raid5_packet *wp, return (0); } + +/* Calculate the offsets in the various subdisks for a RAID5 request. */ +int +gv_raid5_offset(struct gv_plex *p, off_t boff, off_t bcount, off_t *real_off, + off_t *real_len, int *sdno, int *psdno) +{ + int sd, psd; + off_t len_left, stripeend, stripeoff, stripestart; + + /* The number of the subdisk containing the parity stripe. */ + psd = p->sdcount - 1 - ( boff / (p->stripesize * (p->sdcount - 1))) % + p->sdcount; + KASSERT(psdno >= 0, ("gv_raid5_offset: psdno < 0")); + + /* Offset of the start address from the start of the stripe. */ + stripeoff = boff % (p->stripesize * (p->sdcount - 1)); + KASSERT(stripeoff >= 0, ("gv_raid5_offset: stripeoff < 0")); + + /* The number of the subdisk where the stripe resides. */ + sd = stripeoff / p->stripesize; + KASSERT(sdno >= 0, ("gv_raid5_offset: sdno < 0")); + + /* At or past parity subdisk. */ + if (sd >= psd) + sd++; + + /* The offset of the stripe on this subdisk. */ + stripestart = (boff - stripeoff) / (p->sdcount - 1); + KASSERT(stripestart >= 0, ("gv_raid5_offset: stripestart < 0")); + + stripeoff %= p->stripesize; + + /* The offset of the request on this subdisk. */ + *real_off = stripestart + stripeoff; + + stripeend = stripestart + p->stripesize; + len_left = stripeend - *real_off; + KASSERT(len_left >= 0, ("gv_raid5_offset: len_left < 0")); + + *real_len = (bcount <= len_left) ? bcount : len_left; + + if (sdno != NULL) + *sdno = sd; + if (psdno != NULL) + *psdno = psd; + + return (0); +} -- cgit v1.1