freebsd-dev/sys/geom/geom_slice.c
Dag-Erling Smørgrav 2616144e43 Add sbuf_new_auto as a shortcut for the very common case of creating a
completely dynamic sbuf.

Obtained from:	Varnish
MFC after:	2 weeks
2008-08-09 11:14:05 +00:00

532 lines
14 KiB
C

/*-
* Copyright (c) 2002 Poul-Henning Kamp
* Copyright (c) 2002 Networks Associates Technology, Inc.
* All rights reserved.
*
* This software was developed for the FreeBSD Project by Poul-Henning Kamp
* and NAI Labs, the Security Research Division of Network Associates, Inc.
* under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
* DARPA CHATS research program.
*
* 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.
* 3. The names of the authors may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* 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/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/bio.h>
#include <sys/sysctl.h>
#include <sys/proc.h>
#include <sys/kthread.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/errno.h>
#include <sys/sbuf.h>
#include <geom/geom.h>
#include <geom/geom_slice.h>
#include <machine/stdarg.h>
static g_access_t g_slice_access;
static g_start_t g_slice_start;
static struct g_slicer *
g_slice_alloc(unsigned nslice, unsigned scsize)
{
struct g_slicer *gsp;
gsp = g_malloc(sizeof *gsp, M_WAITOK | M_ZERO);
if (scsize > 0)
gsp->softc = g_malloc(scsize, M_WAITOK | M_ZERO);
else
gsp->softc = NULL;
gsp->slices = g_malloc(nslice * sizeof(struct g_slice),
M_WAITOK | M_ZERO);
gsp->nslice = nslice;
return (gsp);
}
static void
g_slice_free(struct g_slicer *gsp)
{
if (gsp == NULL) /* XXX: phk thinks about this */
return;
g_free(gsp->slices);
if (gsp->hotspot != NULL)
g_free(gsp->hotspot);
if (gsp->softc != NULL)
g_free(gsp->softc);
g_free(gsp);
}
static int
g_slice_access(struct g_provider *pp, int dr, int dw, int de)
{
int error;
u_int u;
struct g_geom *gp;
struct g_consumer *cp;
struct g_provider *pp2;
struct g_slicer *gsp;
struct g_slice *gsl, *gsl2;
gp = pp->geom;
cp = LIST_FIRST(&gp->consumer);
KASSERT (cp != NULL, ("g_slice_access but no consumer"));
gsp = gp->softc;
if (dr > 0 || dw > 0 || de > 0) {
gsl = &gsp->slices[pp->index];
for (u = 0; u < gsp->nslice; u++) {
gsl2 = &gsp->slices[u];
if (gsl2->length == 0)
continue;
if (u == pp->index)
continue;
if (gsl->offset + gsl->length <= gsl2->offset)
continue;
if (gsl2->offset + gsl2->length <= gsl->offset)
continue;
/* overlap */
pp2 = gsl2->provider;
if ((pp->acw + dw) > 0 && pp2->ace > 0)
return (EPERM);
if ((pp->ace + de) > 0 && pp2->acw > 0)
return (EPERM);
}
}
/* On first open, grab an extra "exclusive" bit */
if (cp->acr == 0 && cp->acw == 0 && cp->ace == 0)
de++;
/* ... and let go of it on last close */
if ((cp->acr + dr) == 0 && (cp->acw + dw) == 0 && (cp->ace + de) == 1)
de--;
error = g_access(cp, dr, dw, de);
return (error);
}
/*
* XXX: It should be possible to specify here if we should finish all of the
* XXX: bio, or only the non-hot bits. This would get messy if there were
* XXX: two hot spots in the same bio, so for now we simply finish off the
* XXX: entire bio. Modifying hot data on the way to disk is frowned on
* XXX: so making that considerably harder is not a bad idea anyway.
*/
void
g_slice_finish_hot(struct bio *bp)
{
struct bio *bp2;
struct g_geom *gp;
struct g_consumer *cp;
struct g_slicer *gsp;
struct g_slice *gsl;
int idx;
KASSERT(bp->bio_to != NULL,
("NULL bio_to in g_slice_finish_hot(%p)", bp));
KASSERT(bp->bio_from != NULL,
("NULL bio_from in g_slice_finish_hot(%p)", bp));
gp = bp->bio_to->geom;
gsp = gp->softc;
cp = LIST_FIRST(&gp->consumer);
KASSERT(cp != NULL, ("NULL consumer in g_slice_finish_hot(%p)", bp));
idx = bp->bio_to->index;
gsl = &gsp->slices[idx];
bp2 = g_clone_bio(bp);
if (bp2 == NULL) {
g_io_deliver(bp, ENOMEM);
return;
}
if (bp2->bio_offset + bp2->bio_length > gsl->length)
bp2->bio_length = gsl->length - bp2->bio_offset;
bp2->bio_done = g_std_done;
bp2->bio_offset += gsl->offset;
g_io_request(bp2, cp);
return;
}
static void
g_slice_done(struct bio *bp)
{
KASSERT(bp->bio_cmd == BIO_GETATTR &&
strcmp(bp->bio_attribute, "GEOM::ident") == 0,
("bio_cmd=0x%x bio_attribute=%s", bp->bio_cmd, bp->bio_attribute));
if (bp->bio_error == 0 && bp->bio_data[0] != '\0') {
char idx[8];
/* Add index to the ident received. */
snprintf(idx, sizeof(idx), "s%d",
bp->bio_parent->bio_to->index);
if (strlcat(bp->bio_data, idx, bp->bio_length) >=
bp->bio_length) {
bp->bio_error = EFAULT;
}
}
g_std_done(bp);
}
static void
g_slice_start(struct bio *bp)
{
struct bio *bp2;
struct g_provider *pp;
struct g_geom *gp;
struct g_consumer *cp;
struct g_slicer *gsp;
struct g_slice *gsl;
struct g_slice_hot *ghp;
int idx, error;
u_int m_index;
off_t t;
pp = bp->bio_to;
gp = pp->geom;
gsp = gp->softc;
cp = LIST_FIRST(&gp->consumer);
idx = pp->index;
gsl = &gsp->slices[idx];
switch(bp->bio_cmd) {
case BIO_READ:
case BIO_WRITE:
case BIO_DELETE:
if (bp->bio_offset > gsl->length) {
g_io_deliver(bp, EINVAL); /* XXX: EWHAT ? */
return;
}
/*
* Check if we collide with any hot spaces, and call the
* method once if so.
*/
t = bp->bio_offset + gsl->offset;
for (m_index = 0; m_index < gsp->nhotspot; m_index++) {
ghp = &gsp->hotspot[m_index];
if (t >= ghp->offset + ghp->length)
continue;
if (t + bp->bio_length <= ghp->offset)
continue;
switch(bp->bio_cmd) {
case BIO_READ: idx = ghp->ract; break;
case BIO_WRITE: idx = ghp->wact; break;
case BIO_DELETE: idx = ghp->dact; break;
}
switch(idx) {
case G_SLICE_HOT_ALLOW:
/* Fall out and continue normal processing */
continue;
case G_SLICE_HOT_DENY:
g_io_deliver(bp, EROFS);
return;
case G_SLICE_HOT_START:
error = gsp->start(bp);
if (error && error != EJUSTRETURN)
g_io_deliver(bp, error);
return;
case G_SLICE_HOT_CALL:
error = g_post_event(gsp->hot, bp, M_NOWAIT,
gp, NULL);
if (error)
g_io_deliver(bp, error);
return;
}
break;
}
bp2 = g_clone_bio(bp);
if (bp2 == NULL) {
g_io_deliver(bp, ENOMEM);
return;
}
if (bp2->bio_offset + bp2->bio_length > gsl->length)
bp2->bio_length = gsl->length - bp2->bio_offset;
bp2->bio_done = g_std_done;
bp2->bio_offset += gsl->offset;
g_io_request(bp2, cp);
return;
case BIO_GETATTR:
/* Give the real method a chance to override */
if (gsp->start != NULL && gsp->start(bp))
return;
if (!strcmp("GEOM::ident", bp->bio_attribute)) {
bp2 = g_clone_bio(bp);
if (bp2 == NULL) {
g_io_deliver(bp, ENOMEM);
return;
}
bp2->bio_done = g_slice_done;
g_io_request(bp2, cp);
return;
}
if (!strcmp("GEOM::kerneldump", bp->bio_attribute)) {
struct g_kerneldump *gkd;
gkd = (struct g_kerneldump *)bp->bio_data;
gkd->offset += gsp->slices[idx].offset;
if (gkd->length > gsp->slices[idx].length)
gkd->length = gsp->slices[idx].length;
/* now, pass it on downwards... */
}
/* FALLTHROUGH */
case BIO_FLUSH:
bp2 = g_clone_bio(bp);
if (bp2 == NULL) {
g_io_deliver(bp, ENOMEM);
return;
}
bp2->bio_done = g_std_done;
g_io_request(bp2, cp);
break;
default:
g_io_deliver(bp, EOPNOTSUPP);
return;
}
}
void
g_slice_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp)
{
struct g_slicer *gsp;
gsp = gp->softc;
if (indent == NULL) {
sbuf_printf(sb, " i %u", pp->index);
sbuf_printf(sb, " o %ju",
(uintmax_t)gsp->slices[pp->index].offset);
return;
}
if (pp != NULL) {
sbuf_printf(sb, "%s<index>%u</index>\n", indent, pp->index);
sbuf_printf(sb, "%s<length>%ju</length>\n",
indent, (uintmax_t)gsp->slices[pp->index].length);
sbuf_printf(sb, "%s<seclength>%ju</seclength>\n", indent,
(uintmax_t)gsp->slices[pp->index].length / 512);
sbuf_printf(sb, "%s<offset>%ju</offset>\n", indent,
(uintmax_t)gsp->slices[pp->index].offset);
sbuf_printf(sb, "%s<secoffset>%ju</secoffset>\n", indent,
(uintmax_t)gsp->slices[pp->index].offset / 512);
}
}
int
g_slice_config(struct g_geom *gp, u_int idx, int how, off_t offset, off_t length, u_int sectorsize, const char *fmt, ...)
{
struct g_provider *pp, *pp2;
struct g_slicer *gsp;
struct g_slice *gsl;
va_list ap;
struct sbuf *sb;
int acc;
g_trace(G_T_TOPOLOGY, "g_slice_config(%s, %d, %d)",
gp->name, idx, how);
g_topology_assert();
gsp = gp->softc;
if (idx >= gsp->nslice)
return(EINVAL);
gsl = &gsp->slices[idx];
pp = gsl->provider;
if (pp != NULL)
acc = pp->acr + pp->acw + pp->ace;
else
acc = 0;
if (acc != 0 && how != G_SLICE_CONFIG_FORCE) {
if (length < gsl->length)
return(EBUSY);
if (offset != gsl->offset)
return(EBUSY);
}
/* XXX: check offset + length <= MEDIASIZE */
if (how == G_SLICE_CONFIG_CHECK)
return (0);
gsl->length = length;
gsl->offset = offset;
gsl->sectorsize = sectorsize;
if (length == 0) {
if (pp == NULL)
return (0);
if (bootverbose)
printf("GEOM: Deconfigure %s\n", pp->name);
g_wither_provider(pp, ENXIO);
gsl->provider = NULL;
gsp->nprovider--;
return (0);
}
if (pp != NULL) {
if (bootverbose)
printf("GEOM: Reconfigure %s, start %jd length %jd end %jd\n",
pp->name, (intmax_t)offset, (intmax_t)length,
(intmax_t)(offset + length - 1));
pp->mediasize = gsl->length;
return (0);
}
sb = sbuf_new_auto();
va_start(ap, fmt);
sbuf_vprintf(sb, fmt, ap);
va_end(ap);
sbuf_finish(sb);
pp = g_new_providerf(gp, sbuf_data(sb));
pp2 = LIST_FIRST(&gp->consumer)->provider;
pp->flags = pp2->flags & G_PF_CANDELETE;
if (pp2->stripesize > 0) {
pp->stripesize = pp2->stripesize;
pp->stripeoffset = (pp2->stripeoffset + offset) % pp->stripesize;
}
if (0 && bootverbose)
printf("GEOM: Configure %s, start %jd length %jd end %jd\n",
pp->name, (intmax_t)offset, (intmax_t)length,
(intmax_t)(offset + length - 1));
pp->index = idx;
pp->mediasize = gsl->length;
pp->sectorsize = gsl->sectorsize;
gsl->provider = pp;
gsp->nprovider++;
g_error_provider(pp, 0);
sbuf_delete(sb);
return(0);
}
/*
* Configure "hotspots". A hotspot is a piece of the parent device which
* this particular slicer cares about for some reason. Typically because
* it contains meta-data used to configure the slicer.
* A hotspot is identified by its index number. The offset and length are
* relative to the parent device, and the three "?act" fields specify
* what action to take on BIO_READ, BIO_DELETE and BIO_WRITE.
*
* XXX: There may be a race relative to g_slice_start() here, if an existing
* XXX: hotspot is changed wile I/O is happening. Should this become a problem
* XXX: we can protect the hotspot stuff with a mutex.
*/
int
g_slice_conf_hot(struct g_geom *gp, u_int idx, off_t offset, off_t length, int ract, int dact, int wact)
{
struct g_slicer *gsp;
struct g_slice_hot *gsl, *gsl2;
g_trace(G_T_TOPOLOGY, "g_slice_conf_hot(%s, idx: %d, off: %jd, len: %jd)",
gp->name, idx, (intmax_t)offset, (intmax_t)length);
g_topology_assert();
gsp = gp->softc;
gsl = gsp->hotspot;
if(idx >= gsp->nhotspot) {
gsl2 = g_malloc((idx + 1) * sizeof *gsl2, M_WAITOK | M_ZERO);
if (gsp->hotspot != NULL)
bcopy(gsp->hotspot, gsl2, gsp->nhotspot * sizeof *gsl2);
gsp->hotspot = gsl2;
if (gsp->hotspot != NULL)
g_free(gsl);
gsl = gsl2;
gsp->nhotspot = idx + 1;
}
gsl[idx].offset = offset;
gsl[idx].length = length;
KASSERT(!((ract | dact | wact) & G_SLICE_HOT_START)
|| gsp->start != NULL, ("G_SLICE_HOT_START but no slice->start"));
/* XXX: check that we _have_ a start function if HOT_START specified */
gsl[idx].ract = ract;
gsl[idx].dact = dact;
gsl[idx].wact = wact;
return (0);
}
void
g_slice_spoiled(struct g_consumer *cp)
{
struct g_geom *gp;
struct g_slicer *gsp;
g_topology_assert();
gp = cp->geom;
g_trace(G_T_TOPOLOGY, "g_slice_spoiled(%p/%s)", cp, gp->name);
gsp = gp->softc;
gp->softc = NULL;
g_slice_free(gsp);
g_wither_geom(gp, ENXIO);
}
int
g_slice_destroy_geom(struct gctl_req *req, struct g_class *mp, struct g_geom *gp)
{
g_slice_spoiled(LIST_FIRST(&gp->consumer));
return (0);
}
struct g_geom *
g_slice_new(struct g_class *mp, u_int slices, struct g_provider *pp, struct g_consumer **cpp, void *extrap, int extra, g_slice_start_t *start)
{
struct g_geom *gp;
struct g_slicer *gsp;
struct g_consumer *cp;
void **vp;
int error;
g_topology_assert();
vp = (void **)extrap;
gp = g_new_geomf(mp, "%s", pp->name);
gsp = g_slice_alloc(slices, extra);
gsp->start = start;
gp->access = g_slice_access;
gp->orphan = g_slice_orphan;
gp->softc = gsp;
gp->start = g_slice_start;
gp->spoiled = g_slice_spoiled;
if (gp->dumpconf == NULL)
gp->dumpconf = g_slice_dumpconf;
if (gp->class->destroy_geom == NULL)
gp->class->destroy_geom = g_slice_destroy_geom;
cp = g_new_consumer(gp);
error = g_attach(cp, pp);
if (error == 0)
error = g_access(cp, 1, 0, 0);
if (error) {
g_wither_geom(gp, ENXIO);
return (NULL);
}
if (extrap != NULL)
*vp = gsp->softc;
*cpp = cp;
return (gp);
}
void
g_slice_orphan(struct g_consumer *cp)
{
g_trace(G_T_TOPOLOGY, "g_slice_orphan(%p/%s)", cp, cp->provider->name);
g_topology_assert();
KASSERT(cp->provider->error != 0,
("g_slice_orphan with error == 0"));
/* XXX: Not good enough we leak the softc and its suballocations */
g_slice_free(cp->geom->softc);
g_wither_geom(cp->geom, cp->provider->error);
}