NetBSD-5.0.2/sys/arch/x86/x86/sys_machdep.c
/* $NetBSD: sys_machdep.c,v 1.15.8.1 2009/04/04 17:39:09 snj Exp $ */
/*-
* Copyright (c) 1998, 2007, 2009 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Charles M. Hannum, and by Andrew Doran.
*
* 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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>
__KERNEL_RCSID(0, "$NetBSD: sys_machdep.c,v 1.15.8.1 2009/04/04 17:39:09 snj Exp $");
#include "opt_compat_netbsd.h"
#include "opt_mtrr.h"
#include "opt_perfctrs.h"
#include "opt_user_ldt.h"
#include "opt_vm86.h"
#include "opt_xen.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/ioctl.h>
#include <sys/file.h>
#include <sys/time.h>
#include <sys/proc.h>
#include <sys/user.h>
#include <sys/uio.h>
#include <sys/kernel.h>
#include <sys/buf.h>
#include <sys/signal.h>
#include <sys/malloc.h>
#include <sys/kmem.h>
#include <sys/kauth.h>
#include <sys/cpu.h>
#include <sys/mount.h>
#include <sys/syscallargs.h>
#include <uvm/uvm_extern.h>
#include <machine/cpufunc.h>
#include <machine/gdt.h>
#include <machine/psl.h>
#include <machine/reg.h>
#include <machine/sysarch.h>
#include <machine/mtrr.h>
#ifdef __x86_64__
/* Need to be checked. */
#undef USER_LDT
#undef PERFCTRS
#undef VM86
#undef IOPERM
#else
#if defined(XEN)
#undef IOPERM
#else /* defined(XEN) */
#define IOPERM
#endif /* defined(XEN) */
#endif
#ifdef VM86
#include <machine/vm86.h>
#endif
#ifdef PERFCTRS
#include <machine/pmc.h>
#endif
extern struct vm_map *kernel_map;
int x86_get_ioperm(struct lwp *, void *, register_t *);
int x86_set_ioperm(struct lwp *, void *, register_t *);
int x86_get_mtrr(struct lwp *, void *, register_t *);
int x86_set_mtrr(struct lwp *, void *, register_t *);
int x86_set_sdbase(void *arg, char which);
int x86_get_sdbase(void *arg, char which);
#ifdef LDT_DEBUG
static void x86_print_ldt(int, const struct segment_descriptor *);
static void
x86_print_ldt(int i, const struct segment_descriptor *d)
{
printf("[%d] lolimit=0x%x, lobase=0x%x, type=%u, dpl=%u, p=%u, "
"hilimit=0x%x, xx=%x, def32=%u, gran=%u, hibase=0x%x\n",
i, d->sd_lolimit, d->sd_lobase, d->sd_type, d->sd_dpl, d->sd_p,
d->sd_hilimit, d->sd_xx, d->sd_def32, d->sd_gran, d->sd_hibase);
}
#endif
int
x86_get_ldt(struct lwp *l, void *args, register_t *retval)
{
#ifndef USER_LDT
return EINVAL;
#else
struct x86_get_ldt_args ua;
union descriptor *cp;
int error;
if ((error = copyin(args, &ua, sizeof(ua))) != 0)
return error;
if (ua.num < 0 || ua.num > 8192)
return EINVAL;
cp = malloc(ua.num * sizeof(union descriptor), M_TEMP, M_WAITOK);
if (cp == NULL)
return ENOMEM;
error = x86_get_ldt1(l, &ua, cp);
*retval = ua.num;
if (error == 0)
error = copyout(cp, ua.desc, ua.num * sizeof(*cp));
free(cp, M_TEMP);
return error;
#endif
}
int
x86_get_ldt1(struct lwp *l, struct x86_get_ldt_args *ua, union descriptor *cp)
{
#ifndef USER_LDT
return EINVAL;
#else
int error;
struct proc *p = l->l_proc;
pmap_t pmap = p->p_vmspace->vm_map.pmap;
int nldt, num;
union descriptor *lp;
error = kauth_authorize_machdep(l->l_cred, KAUTH_MACHDEP_LDT_GET,
NULL, NULL, NULL, NULL);
if (error)
return (error);
#ifdef LDT_DEBUG
printf("x86_get_ldt: start=%d num=%d descs=%p\n", ua->start,
ua->num, ua->desc);
#endif
if (ua->start < 0 || ua->num < 0 || ua->start > 8192 || ua->num > 8192 ||
ua->start + ua->num > 8192)
return (EINVAL);
mutex_enter(&cpu_lock);
if (pmap->pm_ldt != NULL) {
nldt = pmap->pm_ldt_len / sizeof(*lp);
lp = pmap->pm_ldt;
} else {
nldt = NLDT;
lp = ldt;
}
if (ua->start > nldt) {
mutex_exit(&cpu_lock);
return (EINVAL);
}
lp += ua->start;
num = min(ua->num, nldt - ua->start);
ua->num = num;
#ifdef LDT_DEBUG
{
int i;
for (i = 0; i < num; i++)
x86_print_ldt(i, &lp[i].sd);
}
#endif
memcpy(cp, lp, num * sizeof(union descriptor));
mutex_exit(&cpu_lock);
return 0;
#endif
}
int
x86_set_ldt(struct lwp *l, void *args, register_t *retval)
{
#ifndef USER_LDT
return EINVAL;
#else
struct x86_set_ldt_args ua;
union descriptor *descv;
int error;
if ((error = copyin(args, &ua, sizeof(ua))) != 0)
return (error);
if (ua.num < 0 || ua.num > 8192)
return EINVAL;
descv = malloc(sizeof (*descv) * ua.num, M_TEMP, M_NOWAIT);
if (descv == NULL)
return ENOMEM;
error = copyin(ua.desc, descv, sizeof (*descv) * ua.num);
if (error == 0)
error = x86_set_ldt1(l, &ua, descv);
*retval = ua.start;
free(descv, M_TEMP);
return error;
#endif
}
int
x86_set_ldt1(struct lwp *l, struct x86_set_ldt_args *ua,
union descriptor *descv)
{
#ifndef USER_LDT
return EINVAL;
#else
int error, i, n, old_sel, new_sel;
struct proc *p = l->l_proc;
pmap_t pmap = p->p_vmspace->vm_map.pmap;
size_t old_len, new_len;
union descriptor *old_ldt, *new_ldt;
error = kauth_authorize_machdep(l->l_cred, KAUTH_MACHDEP_LDT_SET,
NULL, NULL, NULL, NULL);
if (error)
return (error);
if (ua->start < 0 || ua->num < 0 || ua->start > 8192 || ua->num > 8192 ||
ua->start + ua->num > 8192)
return (EINVAL);
/* Check descriptors for access violations. */
for (i = 0; i < ua->num; i++) {
union descriptor *desc = &descv[i];
switch (desc->sd.sd_type) {
case SDT_SYSNULL:
desc->sd.sd_p = 0;
break;
case SDT_SYS286CGT:
case SDT_SYS386CGT:
/*
* Only allow call gates targeting a segment
* in the LDT or a user segment in the fixed
* part of the gdt. Segments in the LDT are
* constrained (below) to be user segments.
*/
if (desc->gd.gd_p != 0 &&
!ISLDT(desc->gd.gd_selector) &&
((IDXSEL(desc->gd.gd_selector) >= NGDT) ||
(gdt[IDXSEL(desc->gd.gd_selector)].sd.sd_dpl !=
SEL_UPL))) {
return EACCES;
}
break;
case SDT_MEMEC:
case SDT_MEMEAC:
case SDT_MEMERC:
case SDT_MEMERAC:
/* Must be "present" if executable and conforming. */
if (desc->sd.sd_p == 0)
return EACCES;
break;
case SDT_MEMRO:
case SDT_MEMROA:
case SDT_MEMRW:
case SDT_MEMRWA:
case SDT_MEMROD:
case SDT_MEMRODA:
case SDT_MEMRWD:
case SDT_MEMRWDA:
case SDT_MEME:
case SDT_MEMEA:
case SDT_MEMER:
case SDT_MEMERA:
break;
default:
/*
* Make sure that unknown descriptor types are
* not marked present.
*/
if (desc->sd.sd_p != 0)
return EACCES;
break;
}
if (desc->sd.sd_p != 0) {
/* Only user (ring-3) descriptors may be present. */
if (desc->sd.sd_dpl != SEL_UPL)
return EACCES;
}
}
/*
* Install selected changes. We perform a copy, write, swap dance
* here to ensure that all updates happen atomically.
*/
/* Allocate a new LDT. */
for (;;) {
new_len = (ua->start + ua->num) * sizeof(union descriptor);
new_len = max(new_len, pmap->pm_ldt_len);
new_len = max(new_len, NLDT * sizeof(union descriptor));
new_len = round_page(new_len);
new_ldt = (union descriptor *)uvm_km_alloc(kernel_map,
new_len, 0, UVM_KMF_WIRED | UVM_KMF_ZERO);
mutex_enter(&cpu_lock);
if (pmap->pm_ldt_len <= new_len) {
break;
}
mutex_exit(&cpu_lock);
uvm_km_free(kernel_map, (vaddr_t)new_ldt, new_len,
UVM_KMF_WIRED);
}
/* Copy existing entries, if any. */
if (pmap->pm_ldt != NULL) {
old_ldt = pmap->pm_ldt;
old_len = pmap->pm_ldt_len;
old_sel = pmap->pm_ldt_sel;
memcpy(new_ldt, old_ldt, old_len);
} else {
old_ldt = NULL;
old_len = 0;
old_sel = -1;
memcpy(new_ldt, ldt, NLDT * sizeof(union descriptor));
}
/* Apply requested changes. */
for (i = 0, n = ua->start; i < ua->num; i++, n++) {
new_ldt[n] = descv[i];
}
/* Allocate LDT selector. */
new_sel = ldt_alloc(new_ldt, new_len);
if (new_sel == -1) {
mutex_exit(&cpu_lock);
uvm_km_free(kernel_map, (vaddr_t)new_ldt, new_len,
UVM_KMF_WIRED);
return ENOMEM;
}
/* All changes are now globally visible. Swap in the new LDT. */
pmap->pm_ldt = new_ldt;
pmap->pm_ldt_len = new_len;
pmap->pm_ldt_sel = new_sel;
/* Switch existing users onto new LDT. */
pmap_ldt_sync(pmap);
/* Free existing LDT (if any). */
if (old_ldt != NULL) {
ldt_free(old_sel);
uvm_km_free(kernel_map, (vaddr_t)old_ldt, old_len,
UVM_KMF_WIRED);
}
mutex_exit(&cpu_lock);
return error;
#endif
}
int
x86_iopl(struct lwp *l, void *args, register_t *retval)
{
int error;
struct x86_iopl_args ua;
#ifdef XEN
int iopl;
#else
struct trapframe *tf = l->l_md.md_regs;
#endif
error = kauth_authorize_machdep(l->l_cred, KAUTH_MACHDEP_IOPL,
NULL, NULL, NULL, NULL);
if (error)
return (error);
if ((error = copyin(args, &ua, sizeof(ua))) != 0)
return error;
#ifdef XEN
if (ua.iopl)
iopl = SEL_UPL;
else
iopl = SEL_KPL;
l->l_addr->u_pcb.pcb_iopl = iopl;
/* Force the change at ring 0. */
#ifdef XEN3
{
struct physdev_op physop;
physop.cmd = PHYSDEVOP_SET_IOPL;
physop.u.set_iopl.iopl = iopl;
HYPERVISOR_physdev_op(&physop);
}
#else /* XEN3 */
{
dom0_op_t op;
op.cmd = DOM0_IOPL;
op.u.iopl.domain = DOMID_SELF;
op.u.iopl.iopl = iopl;
HYPERVISOR_dom0_op(&op);
}
#endif /* XEN3 */
#elif defined(__x86_64__)
if (ua.iopl)
tf->tf_rflags |= PSL_IOPL;
else
tf->tf_rflags &= ~PSL_IOPL;
#else
if (ua.iopl)
tf->tf_eflags |= PSL_IOPL;
else
tf->tf_eflags &= ~PSL_IOPL;
#endif
return 0;
}
int
x86_get_ioperm(struct lwp *l, void *args, register_t *retval)
{
#ifdef IOPERM
int error;
struct pcb *pcb = &l->l_addr->u_pcb;
struct x86_get_ioperm_args ua;
void *dummymap = NULL;
void *iomap;
error = kauth_authorize_machdep(l->l_cred, KAUTH_MACHDEP_IOPERM_GET,
NULL, NULL, NULL, NULL);
if (error)
return (error);
if ((error = copyin(args, &ua, sizeof(ua))) != 0)
return (error);
iomap = pcb->pcb_iomap;
if (iomap == NULL) {
iomap = dummymap = kmem_alloc(IOMAPSIZE, KM_SLEEP);
memset(dummymap, 0xff, IOMAPSIZE);
}
error = copyout(iomap, ua.iomap, IOMAPSIZE);
if (dummymap != NULL) {
kmem_free(dummymap, IOMAPSIZE);
}
return error;
#else
return EINVAL;
#endif
}
int
x86_set_ioperm(struct lwp *l, void *args, register_t *retval)
{
#ifdef IOPERM
struct cpu_info *ci;
int error;
struct pcb *pcb = &l->l_addr->u_pcb;
struct x86_set_ioperm_args ua;
void *new;
void *old;
error = kauth_authorize_machdep(l->l_cred, KAUTH_MACHDEP_IOPERM_SET,
NULL, NULL, NULL, NULL);
if (error)
return (error);
if ((error = copyin(args, &ua, sizeof(ua))) != 0)
return (error);
new = kmem_alloc(IOMAPSIZE, KM_SLEEP);
error = copyin(ua.iomap, new, IOMAPSIZE);
if (error) {
kmem_free(new, IOMAPSIZE);
return error;
}
old = pcb->pcb_iomap;
pcb->pcb_iomap = new;
if (old != NULL) {
kmem_free(old, IOMAPSIZE);
}
kpreempt_disable();
ci = curcpu();
memcpy(ci->ci_iomap, pcb->pcb_iomap, sizeof(ci->ci_iomap));
ci->ci_tss.tss_iobase =
((uintptr_t)ci->ci_iomap - (uintptr_t)&ci->ci_tss) << 16;
kpreempt_enable();
return error;
#else
return EINVAL;
#endif
}
int
x86_get_mtrr(struct lwp *l, void *args, register_t *retval)
{
#ifdef MTRR
struct x86_get_mtrr_args ua;
int error, n;
if (mtrr_funcs == NULL)
return ENOSYS;
error = kauth_authorize_machdep(l->l_cred, KAUTH_MACHDEP_MTRR_GET,
NULL, NULL, NULL, NULL);
if (error)
return (error);
error = copyin(args, &ua, sizeof ua);
if (error != 0)
return error;
error = copyin(ua.n, &n, sizeof n);
if (error != 0)
return error;
KERNEL_LOCK(1, NULL);
error = mtrr_get(ua.mtrrp, &n, l->l_proc, MTRR_GETSET_USER);
KERNEL_UNLOCK_ONE(NULL);
copyout(&n, ua.n, sizeof (int));
return error;
#else
return EINVAL;
#endif
}
int
x86_set_mtrr(struct lwp *l, void *args, register_t *retval)
{
#ifdef MTRR
int error, n;
struct x86_set_mtrr_args ua;
if (mtrr_funcs == NULL)
return ENOSYS;
error = kauth_authorize_machdep(l->l_cred, KAUTH_MACHDEP_MTRR_SET,
NULL, NULL, NULL, NULL);
if (error)
return (error);
error = copyin(args, &ua, sizeof ua);
if (error != 0)
return error;
error = copyin(ua.n, &n, sizeof n);
if (error != 0)
return error;
KERNEL_LOCK(1, NULL);
error = mtrr_set(ua.mtrrp, &n, l->l_proc, MTRR_GETSET_USER);
if (n != 0)
mtrr_commit();
KERNEL_UNLOCK_ONE(NULL);
copyout(&n, ua.n, sizeof n);
return error;
#else
return EINVAL;
#endif
}
int
x86_set_sdbase(void *arg, char which)
{
#ifdef i386
struct segment_descriptor sd;
vaddr_t base;
int error;
error = copyin(arg, &base, sizeof(base));
if (error != 0)
return error;
sd.sd_lobase = base & 0xffffff;
sd.sd_hibase = (base >> 24) & 0xff;
sd.sd_lolimit = 0xffff;
sd.sd_hilimit = 0xf;
sd.sd_type = SDT_MEMRWA;
sd.sd_dpl = SEL_UPL;
sd.sd_p = 1;
sd.sd_xx = 0;
sd.sd_def32 = 1;
sd.sd_gran = 1;
kpreempt_disable();
if (which == 'f') {
memcpy(&curpcb->pcb_fsd, &sd, sizeof(sd));
memcpy(&curcpu()->ci_gdt[GUFS_SEL], &sd, sizeof(sd));
} else /* which == 'g' */ {
memcpy(&curpcb->pcb_gsd, &sd, sizeof(sd));
memcpy(&curcpu()->ci_gdt[GUGS_SEL], &sd, sizeof(sd));
}
kpreempt_enable();
return 0;
#else
return EINVAL;
#endif
}
int
x86_get_sdbase(void *arg, char which)
{
#ifdef i386
struct segment_descriptor *sd;
vaddr_t base;
switch (which) {
case 'f':
sd = (struct segment_descriptor *)&curpcb->pcb_fsd;
break;
case 'g':
sd = (struct segment_descriptor *)&curpcb->pcb_gsd;
break;
default:
panic("x86_get_sdbase");
}
base = sd->sd_hibase << 24 | sd->sd_lobase;
return copyout(&base, &arg, sizeof(base));
#else
return EINVAL;
#endif
}
int
sys_sysarch(struct lwp *l, const struct sys_sysarch_args *uap, register_t *retval)
{
/* {
syscallarg(int) op;
syscallarg(void *) parms;
} */
int error = 0;
switch(SCARG(uap, op)) {
case X86_IOPL:
error = x86_iopl(l, SCARG(uap, parms), retval);
break;
case X86_GET_LDT:
error = x86_get_ldt(l, SCARG(uap, parms), retval);
break;
case X86_SET_LDT:
error = x86_set_ldt(l, SCARG(uap, parms), retval);
break;
case X86_GET_IOPERM:
error = x86_get_ioperm(l, SCARG(uap, parms), retval);
break;
case X86_SET_IOPERM:
error = x86_set_ioperm(l, SCARG(uap, parms), retval);
break;
case X86_GET_MTRR:
error = x86_get_mtrr(l, SCARG(uap, parms), retval);
break;
case X86_SET_MTRR:
error = x86_set_mtrr(l, SCARG(uap, parms), retval);
break;
#ifdef VM86
case X86_VM86:
error = x86_vm86(l, SCARG(uap, parms), retval);
break;
#ifdef COMPAT_16
case X86_OLD_VM86:
error = compat_16_x86_vm86(l, SCARG(uap, parms), retval);
break;
#endif
#endif
#ifdef PERFCTRS
case X86_PMC_INFO:
KERNEL_LOCK(1, NULL);
error = pmc_info(l, SCARG(uap, parms), retval);
KERNEL_UNLOCK_ONE(NULL);
break;
case X86_PMC_STARTSTOP:
KERNEL_LOCK(1, NULL);
error = pmc_startstop(l, SCARG(uap, parms), retval);
KERNEL_UNLOCK_ONE(NULL);
break;
case X86_PMC_READ:
KERNEL_LOCK(1, NULL);
error = pmc_read(l, SCARG(uap, parms), retval);
KERNEL_UNLOCK_ONE(NULL);
break;
#endif
case X86_SET_FSBASE:
error = x86_set_sdbase(SCARG(uap, parms), 'f');
break;
case X86_SET_GSBASE:
error = x86_set_sdbase(SCARG(uap, parms), 'g');
break;
case X86_GET_FSBASE:
error = x86_get_sdbase(SCARG(uap, parms), 'f');
break;
case X86_GET_GSBASE:
error = x86_get_sdbase(SCARG(uap, parms), 'g');
break;
default:
error = EINVAL;
break;
}
return (error);
}