freebsd-dev/sys/geom/vinum/geom_vinum_volume.c
Lukas Ertl 4328802ce9 When attaching a consumer from a volume to a plex, check if the
volume already has a plex attached and adjust the access counts
of the new consumer accordingly.
2004-08-26 21:04:41 +00:00

281 lines
6.6 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/bio.h>
#include <sys/conf.h>
#include <sys/kernel.h>
#include <sys/libkern.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/systm.h>
#include <geom/geom.h>
#include <geom/vinum/geom_vinum_var.h>
#include <geom/vinum/geom_vinum.h>
static void
gv_volume_orphan(struct g_consumer *cp)
{
struct g_geom *gp;
struct gv_volume *v;
int error;
g_topology_assert();
gp = cp->geom;
g_trace(G_T_TOPOLOGY, "gv_volume_orphan(%s)", gp->name);
if (cp->acr != 0 || cp->acw != 0 || cp->ace != 0)
g_access(cp, -cp->acr, -cp->acw, -cp->ace);
error = cp->provider->error;
if (error == 0)
error = ENXIO;
g_detach(cp);
g_destroy_consumer(cp);
if (!LIST_EMPTY(&gp->consumer))
return;
v = gp->softc;
if (v != NULL)
v->geom = NULL;
gp->softc = NULL;
g_wither_geom(gp, error);
}
/* We end up here after the requests to our plexes are done. */
static void
gv_volume_done(struct bio *bp)
{
struct g_consumer *cp;
/* The next plex in this volume. */
cp = LIST_NEXT(bp->bio_from, consumer);
switch (bp->bio_cmd) {
case BIO_READ:
/*
* If no error occured on this request, or if we have no plex
* left, finish here...
*/
if ((bp->bio_error == 0) || (cp == NULL)) {
g_std_done(bp);
return;
}
/* ... or try to read from the next plex. */
g_io_request(bp, cp);
return;
case BIO_WRITE:
case BIO_DELETE:
/* No more plexes left. */
if (cp == NULL) {
/*
* Clear any errors if one of the previous writes
* succeeded.
*/
if (bp->bio_caller1 == (int *)1)
bp->bio_error = 0;
g_std_done(bp);
return;
}
/* If this write request had no errors, remember that fact... */
if (bp->bio_error == 0)
bp->bio_caller1 = (int *)1;
/* ... and write to the next plex. */
g_io_request(bp, cp);
return;
}
}
static void
gv_volume_start(struct bio *bp)
{
struct g_geom *gp;
struct bio *bp2;
struct gv_volume *v;
gp = bp->bio_to->geom;
v = gp->softc;
if (v->state != GV_VOL_UP) {
g_io_deliver(bp, ENXIO);
return;
}
switch(bp->bio_cmd) {
case BIO_READ:
case BIO_WRITE:
case BIO_DELETE:
bp2 = g_clone_bio(bp);
if (bp2 == NULL) {
g_io_deliver(bp, ENOMEM);
return;
}
bp2->bio_done = gv_volume_done;
g_io_request(bp2, LIST_FIRST(&gp->consumer));
return;
default:
g_io_deliver(bp, EOPNOTSUPP);
return;
}
}
static int
gv_volume_access(struct g_provider *pp, int dr, int dw, int de)
{
struct g_geom *gp;
struct g_consumer *cp, *cp2;
int error;
gp = pp->geom;
error = ENXIO;
LIST_FOREACH(cp, &gp->consumer, consumer) {
error = g_access(cp, dr, dw, de);
if (error) {
LIST_FOREACH(cp2, &gp->consumer, consumer) {
if (cp == cp2)
break;
g_access(cp2, -dr, -dw, -de);
}
return (error);
}
}
return (error);
}
static struct g_geom *
gv_volume_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
{
struct g_geom *gp;
struct g_provider *pp2;
struct g_consumer *cp, *ocp;
struct gv_softc *sc;
struct gv_volume *v;
struct gv_plex *p;
int error, first;
g_trace(G_T_TOPOLOGY, "gv_volume_taste(%s, %s)", mp->name, pp->name);
g_topology_assert();
/* First, find the VINUM class and its associated geom. */
gp = find_vinum_geom();
if (gp == NULL)
return (NULL);
sc = gp->softc;
KASSERT(sc != NULL, ("gv_volume_taste: NULL sc"));
gp = pp->geom;
/* We only want to attach to plexes. */
if (strcmp(gp->class->name, "VINUMPLEX"))
return (NULL);
first = 0;
p = gp->softc;
v = gv_find_vol(sc, p->volume);
if (v == NULL)
return (NULL);
if (v->geom == NULL) {
gp = g_new_geomf(mp, "%s", p->volume);
gp->start = gv_volume_start;
gp->orphan = gv_volume_orphan;
gp->access = gv_volume_access;
gp->softc = v;
first++;
} else
gp = v->geom;
/*
* Create a new consumer and attach it to the plex geom. Since this
* volume might already have a plex attached, we need to adjust the
* access counts of the new consumer.
*/
ocp = LIST_FIRST(&gp->consumer);
cp = g_new_consumer(gp);
g_attach(cp, pp);
if ((ocp != NULL) && (ocp->acr > 0 || ocp->acw > 0 || ocp->ace > 0)) {
error = g_access(cp, ocp->acr, ocp->acw, ocp->ace);
if (error) {
printf("GEOM_VINUM: failed g_access %s -> %s; "
"errno %d\n", v->name, p->name, error);
g_detach(cp);
g_destroy_consumer(cp);
if (first)
g_destroy_geom(gp);
return (NULL);
}
}
p->consumer = cp;
if (p->vol_sc != v) {
p->vol_sc = v;
v->plexcount++;
LIST_INSERT_HEAD(&v->plexes, p, in_volume);
}
/* We need to setup a new VINUMVOLUME geom. */
if (first) {
pp2 = g_new_providerf(gp, "gvinum/%s", v->name);
pp2->mediasize = pp->mediasize;
pp2->sectorsize = pp->sectorsize;
g_error_provider(pp2, 0);
v->size = pp2->mediasize;
v->geom = gp;
return (gp);
}
return (NULL);
}
static int
gv_volume_destroy_geom(struct gctl_req *req, struct g_class *mp,
struct g_geom *gp)
{
g_trace(G_T_TOPOLOGY, "gv_volume_destroy_geom: %s", gp->name);
g_topology_assert();
g_wither_geom(gp, ENXIO);
return (0);
}
#define VINUMVOLUME_CLASS_NAME "VINUMVOLUME"
static struct g_class g_vinum_volume_class = {
.name = VINUMVOLUME_CLASS_NAME,
.version = G_VERSION,
.taste = gv_volume_taste,
.destroy_geom = gv_volume_destroy_geom,
};
DECLARE_GEOM_CLASS(g_vinum_volume_class, g_vinum_volume);