freebsd-skq/sys/geom/geom_pc98.c
attilio 1521eb4479 Avoid to check the same cache line/variable from all the locking
primitives by breaking stop_scheduler into a per-thread variable.
Also, store the new td_stopsched very close to td_*locks members as
they will be accessed mostly in the same codepaths as td_stopsched and
this results in avoiding a further cache-line pollution, possibly.

STOP_SCHEDULER() was pondered to use a new 'thread' argument, in order to
take advantage of already cached curthread, but in the end there should
not really be a performance benefit, while introducing a KPI breakage.

In collabouration with:	flo
Reviewed by:	avg
MFC after:	3 months (or never)
X-MFC:		r228424
2012-01-28 14:00:21 +00:00

374 lines
9.8 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.
*
* 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/endian.h>
#include <sys/systm.h>
#include <sys/sysctl.h>
#include <sys/kernel.h>
#include <sys/fcntl.h>
#include <sys/malloc.h>
#include <sys/bio.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/sbuf.h>
#include <sys/diskpc98.h>
#include <geom/geom.h>
#include <geom/geom_slice.h>
FEATURE(geom_pc98, "GEOM NEC PC9800 partitioning support");
#define PC98_CLASS_NAME "PC98"
struct g_pc98_softc {
u_int fwsectors, fwheads, sectorsize;
int type[NDOSPART];
u_char sec[8192];
};
static void
g_pc98_print(int i, struct pc98_partition *dp)
{
char sname[17];
strncpy(sname, dp->dp_name, 16);
sname[16] = '\0';
hexdump(dp, sizeof(dp[0]), NULL, 0);
printf("[%d] mid:%d(0x%x) sid:%d(0x%x)",
i, dp->dp_mid, dp->dp_mid, dp->dp_sid, dp->dp_sid);
printf(" s:%d/%d/%d", dp->dp_scyl, dp->dp_shd, dp->dp_ssect);
printf(" e:%d/%d/%d", dp->dp_ecyl, dp->dp_ehd, dp->dp_esect);
printf(" sname:%s\n", sname);
}
/*
* XXX: Add gctl_req arg and give good error msgs.
* XXX: Check that length argument does not bring boot code inside any slice.
*/
static int
g_pc98_modify(struct g_geom *gp, struct g_pc98_softc *ms, u_char *sec, int len __unused)
{
int i, error;
off_t s[NDOSPART], l[NDOSPART];
struct pc98_partition dp[NDOSPART];
g_topology_assert();
if (sec[0x1fe] != 0x55 || sec[0x1ff] != 0xaa)
return (EBUSY);
#if 0
/*
* By convetion, it seems that the ipl program has a jump at location
* 0 to the real start of the boot loader. By convetion, it appears
* that after this jump, there's a string, terminated by at last one,
* if not more, zeros, followed by the target of the jump. FreeBSD's
* pc98 boot0 uses 'IPL1' followed by 3 zeros here, likely for
* compatibility with some older boot loader. Linux98's boot loader
* appears to use 'Linux 98' followed by only two. GRUB/98 appears to
* use 'GRUB/98 ' followed by none. These last two appear to be
* ported from the ia32 versions, but appear to show similar
* convention. Grub/98 has an additional NOP after the jmp, which
* isn't present in others.
*
* The following test was inspired by looking only at partitions
* with FreeBSD's boot0 (or one that it is compatible with). As
* such, if failed when other IPL programs were used.
*/
if (sec[4] != 'I' || sec[5] != 'P' || sec[6] != 'L' || sec[7] != '1')
return (EBUSY);
#endif
for (i = 0; i < NDOSPART; i++)
pc98_partition_dec(
sec + 512 + i * sizeof(struct pc98_partition), &dp[i]);
for (i = 0; i < NDOSPART; i++) {
/* If start and end are identical it's bogus */
if (dp[i].dp_ssect == dp[i].dp_esect &&
dp[i].dp_shd == dp[i].dp_ehd &&
dp[i].dp_scyl == dp[i].dp_ecyl)
s[i] = l[i] = 0;
else if (dp[i].dp_ecyl == 0)
s[i] = l[i] = 0;
else {
s[i] = (off_t)dp[i].dp_scyl *
ms->fwsectors * ms->fwheads * ms->sectorsize;
l[i] = (off_t)(dp[i].dp_ecyl - dp[i].dp_scyl + 1) *
ms->fwsectors * ms->fwheads * ms->sectorsize;
}
if (bootverbose) {
printf("PC98 Slice %d on %s:\n", i + 1, gp->name);
g_pc98_print(i, dp + i);
}
if (s[i] < 0 || l[i] < 0)
error = EBUSY;
else
error = g_slice_config(gp, i, G_SLICE_CONFIG_CHECK,
s[i], l[i], ms->sectorsize,
"%ss%d", gp->name, i + 1);
if (error)
return (error);
}
for (i = 0; i < NDOSPART; i++) {
ms->type[i] = (dp[i].dp_sid << 8) | dp[i].dp_mid;
g_slice_config(gp, i, G_SLICE_CONFIG_SET, s[i], l[i],
ms->sectorsize, "%ss%d", gp->name, i + 1);
}
bcopy(sec, ms->sec, sizeof (ms->sec));
return (0);
}
static int
g_pc98_ioctl(struct g_provider *pp, u_long cmd, void *data, int fflag, struct thread *td)
{
struct g_geom *gp;
struct g_pc98_softc *ms;
struct g_slicer *gsp;
struct g_consumer *cp;
int error, opened;
gp = pp->geom;
gsp = gp->softc;
ms = gsp->softc;
opened = 0;
error = 0;
switch(cmd) {
case DIOCSPC98: {
if (!(fflag & FWRITE))
return (EPERM);
DROP_GIANT();
g_topology_lock();
cp = LIST_FIRST(&gp->consumer);
if (cp->acw == 0) {
error = g_access(cp, 0, 1, 0);
if (error == 0)
opened = 1;
}
if (!error)
error = g_pc98_modify(gp, ms, data, 8192);
if (!error)
error = g_write_data(cp, 0, data, 8192);
if (opened)
g_access(cp, 0, -1 , 0);
g_topology_unlock();
PICKUP_GIANT();
return(error);
}
default:
return (ENOIOCTL);
}
}
static int
g_pc98_start(struct bio *bp)
{
struct g_provider *pp;
struct g_geom *gp;
struct g_pc98_softc *mp;
struct g_slicer *gsp;
int idx;
pp = bp->bio_to;
idx = pp->index;
gp = pp->geom;
gsp = gp->softc;
mp = gsp->softc;
if (bp->bio_cmd == BIO_GETATTR) {
if (g_handleattr_int(bp, "PC98::type", mp->type[idx]))
return (1);
if (g_handleattr_off_t(bp, "PC98::offset",
gsp->slices[idx].offset))
return (1);
}
return (0);
}
static void
g_pc98_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
struct g_consumer *cp __unused, struct g_provider *pp)
{
struct g_pc98_softc *mp;
struct g_slicer *gsp;
struct pc98_partition dp;
char sname[17];
gsp = gp->softc;
mp = gsp->softc;
g_slice_dumpconf(sb, indent, gp, cp, pp);
if (pp != NULL) {
pc98_partition_dec(
mp->sec + 512 +
pp->index * sizeof(struct pc98_partition), &dp);
strncpy(sname, dp.dp_name, 16);
sname[16] = '\0';
if (indent == NULL) {
sbuf_printf(sb, " ty %d", mp->type[pp->index]);
sbuf_printf(sb, " sn %s", sname);
} else {
sbuf_printf(sb, "%s<type>%d</type>\n", indent,
mp->type[pp->index]);
sbuf_printf(sb, "%s<sname>%s</sname>\n", indent,
sname);
}
}
}
static struct g_geom *
g_pc98_taste(struct g_class *mp, struct g_provider *pp, int flags)
{
struct g_geom *gp;
struct g_consumer *cp;
int error;
struct g_pc98_softc *ms;
u_int fwsectors, fwheads, sectorsize;
u_char *buf;
g_trace(G_T_TOPOLOGY, "g_pc98_taste(%s,%s)", mp->name, pp->name);
g_topology_assert();
if (flags == G_TF_NORMAL &&
!strcmp(pp->geom->class->name, PC98_CLASS_NAME))
return (NULL);
gp = g_slice_new(mp, NDOSPART, pp, &cp, &ms, sizeof *ms, g_pc98_start);
if (gp == NULL)
return (NULL);
g_topology_unlock();
do {
if (gp->rank != 2 && flags == G_TF_NORMAL)
break;
error = g_getattr("GEOM::fwsectors", cp, &fwsectors);
if (error || fwsectors == 0) {
fwsectors = 17;
if (bootverbose)
printf("g_pc98_taste: guessing %d sectors\n",
fwsectors);
}
error = g_getattr("GEOM::fwheads", cp, &fwheads);
if (error || fwheads == 0) {
fwheads = 8;
if (bootverbose)
printf("g_pc98_taste: guessing %d heads\n",
fwheads);
}
sectorsize = cp->provider->sectorsize;
if (sectorsize % 512 != 0)
break;
buf = g_read_data(cp, 0, 8192, NULL);
if (buf == NULL)
break;
ms->fwsectors = fwsectors;
ms->fwheads = fwheads;
ms->sectorsize = sectorsize;
g_topology_lock();
g_pc98_modify(gp, ms, buf, 8192);
g_topology_unlock();
g_free(buf);
break;
} while (0);
g_topology_lock();
g_access(cp, -1, 0, 0);
if (LIST_EMPTY(&gp->provider)) {
g_slice_spoiled(cp);
return (NULL);
}
return (gp);
}
static void
g_pc98_config(struct gctl_req *req, struct g_class *mp, const char *verb)
{
struct g_geom *gp;
struct g_consumer *cp;
struct g_pc98_softc *ms;
struct g_slicer *gsp;
int opened = 0, error = 0;
void *data;
int len;
g_topology_assert();
gp = gctl_get_geom(req, mp, "geom");
if (gp == NULL)
return;
if (strcmp(verb, "write PC98")) {
gctl_error(req, "Unknown verb");
return;
}
gsp = gp->softc;
ms = gsp->softc;
data = gctl_get_param(req, "data", &len);
if (data == NULL)
return;
if (len < 8192 || (len % 512)) {
gctl_error(req, "Wrong request length");
return;
}
cp = LIST_FIRST(&gp->consumer);
if (cp->acw == 0) {
error = g_access(cp, 0, 1, 0);
if (error == 0)
opened = 1;
}
if (!error)
error = g_pc98_modify(gp, ms, data, len);
if (error)
gctl_error(req, "conflict with open slices");
if (!error)
error = g_write_data(cp, 0, data, len);
if (error)
gctl_error(req, "sector zero write failed");
if (opened)
g_access(cp, 0, -1 , 0);
return;
}
static struct g_class g_pc98_class = {
.name = PC98_CLASS_NAME,
.version = G_VERSION,
.taste = g_pc98_taste,
.dumpconf = g_pc98_dumpconf,
.ctlreq = g_pc98_config,
.ioctl = g_pc98_ioctl,
};
DECLARE_GEOM_CLASS(g_pc98_class, g_pc98);