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freebsd-dev/sys/pc98/i386/machdep.c
Jake Burkholder aff81a81d6 Remove BDE_DEBUGGER. 
Discussed with:	bde
2003-01-28 19:05:44 +00:00

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/*-
* Copyright (c) 1992 Terrence R. Lambert.
* Copyright (c) 1982, 1987, 1990 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* William Jolitz.
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*
* from: @(#)machdep.c 7.4 (Berkeley) 6/3/91
* $FreeBSD$
*/
#include "opt_atalk.h"
#include "opt_compat.h"
#include "opt_cpu.h"
#include "opt_ddb.h"
#include "opt_inet.h"
#include "opt_ipx.h"
#include "opt_isa.h"
#include "opt_maxmem.h"
#include "opt_msgbuf.h"
#include "opt_npx.h"
#include "opt_perfmon.h"
#include "opt_kstack_pages.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/sysproto.h>
#include <sys/signalvar.h>
#include <sys/imgact.h>
#include <sys/kernel.h>
#include <sys/ktr.h>
#include <sys/linker.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mutex.h>
#include <sys/pcpu.h>
#include <sys/proc.h>
#include <sys/bio.h>
#include <sys/buf.h>
#include <sys/reboot.h>
#include <sys/callout.h>
#include <sys/msgbuf.h>
#include <sys/sched.h>
#include <sys/sysent.h>
#include <sys/sysctl.h>
#include <sys/ucontext.h>
#include <sys/vmmeter.h>
#include <sys/bus.h>
#include <sys/eventhandler.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/vm_kern.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>
#include <vm/vm_map.h>
#include <vm/vm_pager.h>
#include <vm/vm_extern.h>
#include <sys/user.h>
#include <sys/exec.h>
#include <sys/cons.h>
#include <ddb/ddb.h>
#include <net/netisr.h>
#include <machine/cpu.h>
#include <machine/cputypes.h>
#include <machine/reg.h>
#include <machine/clock.h>
#include <machine/specialreg.h>
#include <machine/bootinfo.h>
#include <machine/md_var.h>
#include <machine/pc/bios.h>
#include <machine/pcb_ext.h> /* pcb.h included via sys/user.h */
#include <machine/proc.h>
#ifdef PERFMON
#include <machine/perfmon.h>
#endif
#ifdef SMP
#include <machine/privatespace.h>
#include <machine/smp.h>
#endif
#include <i386/isa/icu.h>
#include <i386/isa/intr_machdep.h>
#ifdef PC98
#include <pc98/pc98/pc98_machdep.h>
#include <pc98/pc98/pc98.h>
#else
#include <isa/rtc.h>
#endif
#include <machine/vm86.h>
#include <sys/ptrace.h>
#include <machine/sigframe.h>
extern void init386(int first);
extern void dblfault_handler(void);
extern void printcpuinfo(void); /* XXX header file */
extern void finishidentcpu(void);
extern void panicifcpuunsupported(void);
extern void initializecpu(void);
#define CS_SECURE(cs) (ISPL(cs) == SEL_UPL)
#define EFL_SECURE(ef, oef) ((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0)
#if !defined(CPU_ENABLE_SSE) && defined(I686_CPU)
#define CPU_ENABLE_SSE
#endif
#if defined(CPU_DISABLE_SSE)
#undef CPU_ENABLE_SSE
#endif
static void cpu_startup(void *);
static void fpstate_drop(struct thread *td);
static void get_fpcontext(struct thread *td, mcontext_t *mcp);
static int set_fpcontext(struct thread *td, const mcontext_t *mcp);
#ifdef CPU_ENABLE_SSE
static void set_fpregs_xmm(struct save87 *, struct savexmm *);
static void fill_fpregs_xmm(struct savexmm *, struct save87 *);
#endif /* CPU_ENABLE_SSE */
SYSINIT(cpu, SI_SUB_CPU, SI_ORDER_FIRST, cpu_startup, NULL)
#ifdef PC98
int need_pre_dma_flush; /* If 1, use wbinvd befor DMA transfer. */
int need_post_dma_flush; /* If 1, use invd after DMA transfer. */
#endif
int _udatasel, _ucodesel;
u_int atdevbase;
#if defined(SWTCH_OPTIM_STATS)
extern int swtch_optim_stats;
SYSCTL_INT(_debug, OID_AUTO, swtch_optim_stats,
CTLFLAG_RD, &swtch_optim_stats, 0, "");
SYSCTL_INT(_debug, OID_AUTO, tlb_flush_count,
CTLFLAG_RD, &tlb_flush_count, 0, "");
#endif
#ifdef PC98
static int ispc98 = 1;
#else
static int ispc98 = 0;
#endif
SYSCTL_INT(_machdep, OID_AUTO, ispc98, CTLFLAG_RD, &ispc98, 0, "");
int cold = 1;
#ifdef COMPAT_43
static void osendsig(sig_t catcher, int sig, sigset_t *mask, u_long code);
#endif
#ifdef COMPAT_FREEBSD4
static void freebsd4_sendsig(sig_t catcher, int sig, sigset_t *mask,
u_long code);
#endif
long Maxmem = 0;
#ifdef PC98
int Maxmem_under16M = 0;
#endif
vm_offset_t phys_avail[10];
/* must be 2 less so 0 0 can signal end of chunks */
#define PHYS_AVAIL_ARRAY_END ((sizeof(phys_avail) / sizeof(vm_offset_t)) - 2)
struct kva_md_info kmi;
static struct trapframe proc0_tf;
#ifndef SMP
static struct pcpu __pcpu;
#endif
struct mtx icu_lock;
static void
cpu_startup(dummy)
void *dummy;
{
/*
* Good {morning,afternoon,evening,night}.
*/
startrtclock();
printcpuinfo();
panicifcpuunsupported();
#ifdef PERFMON
perfmon_init();
#endif
printf("real memory = %u (%u MB)\n", ptoa(Maxmem),
ptoa(Maxmem) / 1048576);
/*
* Display any holes after the first chunk of extended memory.
*/
if (bootverbose) {
int indx;
printf("Physical memory chunk(s):\n");
for (indx = 0; phys_avail[indx + 1] != 0; indx += 2) {
unsigned int size1;
size1 = phys_avail[indx + 1] - phys_avail[indx];
printf("0x%08x - 0x%08x, %u bytes (%u pages)\n",
phys_avail[indx], phys_avail[indx + 1] - 1, size1,
size1 / PAGE_SIZE);
}
}
vm_ksubmap_init(&kmi);
printf("avail memory = %u (%u MB)\n", ptoa(cnt.v_free_count),
ptoa(cnt.v_free_count) / 1048576);
/*
* Set up buffers, so they can be used to read disk labels.
*/
bufinit();
vm_pager_bufferinit();
#ifndef SMP
/* For SMP, we delay the cpu_setregs() until after SMP startup. */
cpu_setregs();
#endif
}
/*
* Send an interrupt to process.
*
* Stack is set up to allow sigcode stored
* at top to call routine, followed by kcall
* to sigreturn routine below. After sigreturn
* resets the signal mask, the stack, and the
* frame pointer, it returns to the user
* specified pc, psl.
*/
#ifdef COMPAT_43
static void
osendsig(catcher, sig, mask, code)
sig_t catcher;
int sig;
sigset_t *mask;
u_long code;
{
struct osigframe sf, *fp;
struct proc *p;
struct thread *td;
struct sigacts *psp;
struct trapframe *regs;
int oonstack;
td = curthread;
p = td->td_proc;
PROC_LOCK_ASSERT(p, MA_OWNED);
psp = p->p_sigacts;
regs = td->td_frame;
oonstack = sigonstack(regs->tf_esp);
/* Allocate space for the signal handler context. */
if ((p->p_flag & P_ALTSTACK) && !oonstack &&
SIGISMEMBER(psp->ps_sigonstack, sig)) {
fp = (struct osigframe *)(p->p_sigstk.ss_sp +
p->p_sigstk.ss_size - sizeof(struct osigframe));
#if defined(COMPAT_43) || defined(COMPAT_SUNOS)
p->p_sigstk.ss_flags |= SS_ONSTACK;
#endif
} else
fp = (struct osigframe *)regs->tf_esp - 1;
PROC_UNLOCK(p);
/* Translate the signal if appropriate. */
if (p->p_sysent->sv_sigtbl && sig <= p->p_sysent->sv_sigsize)
sig = p->p_sysent->sv_sigtbl[_SIG_IDX(sig)];
/* Build the argument list for the signal handler. */
sf.sf_signum = sig;
sf.sf_scp = (register_t)&fp->sf_siginfo.si_sc;
PROC_LOCK(p);
if (SIGISMEMBER(p->p_sigacts->ps_siginfo, sig)) {
/* Signal handler installed with SA_SIGINFO. */
sf.sf_arg2 = (register_t)&fp->sf_siginfo;
sf.sf_siginfo.si_signo = sig;
sf.sf_siginfo.si_code = code;
sf.sf_ahu.sf_action = (__osiginfohandler_t *)catcher;
} else {
/* Old FreeBSD-style arguments. */
sf.sf_arg2 = code;
sf.sf_addr = regs->tf_err;
sf.sf_ahu.sf_handler = catcher;
}
PROC_UNLOCK(p);
/* Save most if not all of trap frame. */
sf.sf_siginfo.si_sc.sc_eax = regs->tf_eax;
sf.sf_siginfo.si_sc.sc_ebx = regs->tf_ebx;
sf.sf_siginfo.si_sc.sc_ecx = regs->tf_ecx;
sf.sf_siginfo.si_sc.sc_edx = regs->tf_edx;
sf.sf_siginfo.si_sc.sc_esi = regs->tf_esi;
sf.sf_siginfo.si_sc.sc_edi = regs->tf_edi;
sf.sf_siginfo.si_sc.sc_cs = regs->tf_cs;
sf.sf_siginfo.si_sc.sc_ds = regs->tf_ds;
sf.sf_siginfo.si_sc.sc_ss = regs->tf_ss;
sf.sf_siginfo.si_sc.sc_es = regs->tf_es;
sf.sf_siginfo.si_sc.sc_fs = regs->tf_fs;
sf.sf_siginfo.si_sc.sc_gs = rgs();
sf.sf_siginfo.si_sc.sc_isp = regs->tf_isp;
/* Build the signal context to be used by osigreturn(). */
sf.sf_siginfo.si_sc.sc_onstack = (oonstack) ? 1 : 0;
SIG2OSIG(*mask, sf.sf_siginfo.si_sc.sc_mask);
sf.sf_siginfo.si_sc.sc_sp = regs->tf_esp;
sf.sf_siginfo.si_sc.sc_fp = regs->tf_ebp;
sf.sf_siginfo.si_sc.sc_pc = regs->tf_eip;
sf.sf_siginfo.si_sc.sc_ps = regs->tf_eflags;
sf.sf_siginfo.si_sc.sc_trapno = regs->tf_trapno;
sf.sf_siginfo.si_sc.sc_err = regs->tf_err;
/*
* If we're a vm86 process, we want to save the segment registers.
* We also change eflags to be our emulated eflags, not the actual
* eflags.
*/
if (regs->tf_eflags & PSL_VM) {
/* XXX confusing names: `tf' isn't a trapframe; `regs' is. */
struct trapframe_vm86 *tf = (struct trapframe_vm86 *)regs;
struct vm86_kernel *vm86 = &td->td_pcb->pcb_ext->ext_vm86;
sf.sf_siginfo.si_sc.sc_gs = tf->tf_vm86_gs;
sf.sf_siginfo.si_sc.sc_fs = tf->tf_vm86_fs;
sf.sf_siginfo.si_sc.sc_es = tf->tf_vm86_es;
sf.sf_siginfo.si_sc.sc_ds = tf->tf_vm86_ds;
if (vm86->vm86_has_vme == 0)
sf.sf_siginfo.si_sc.sc_ps =
(tf->tf_eflags & ~(PSL_VIF | PSL_VIP)) |
(vm86->vm86_eflags & (PSL_VIF | PSL_VIP));
/* See sendsig() for comments. */
tf->tf_eflags &= ~(PSL_VM | PSL_NT | PSL_VIF | PSL_VIP);
}
/*
* Copy the sigframe out to the user's stack.
*/
if (copyout(&sf, fp, sizeof(*fp)) != 0) {
#ifdef DEBUG
printf("process %ld has trashed its stack\n", (long)p->p_pid);
#endif
PROC_LOCK(p);
sigexit(td, SIGILL);
}
regs->tf_esp = (int)fp;
regs->tf_eip = PS_STRINGS - szosigcode;
regs->tf_eflags &= ~PSL_T;
regs->tf_cs = _ucodesel;
regs->tf_ds = _udatasel;
regs->tf_es = _udatasel;
regs->tf_fs = _udatasel;
load_gs(_udatasel);
regs->tf_ss = _udatasel;
PROC_LOCK(p);
}
#endif /* COMPAT_43 */
#ifdef COMPAT_FREEBSD4
static void
freebsd4_sendsig(catcher, sig, mask, code)
sig_t catcher;
int sig;
sigset_t *mask;
u_long code;
{
struct sigframe4 sf, *sfp;
struct proc *p;
struct thread *td;
struct sigacts *psp;
struct trapframe *regs;
int oonstack;
td = curthread;
p = td->td_proc;
PROC_LOCK_ASSERT(p, MA_OWNED);
psp = p->p_sigacts;
regs = td->td_frame;
oonstack = sigonstack(regs->tf_esp);
/* Save user context. */
bzero(&sf, sizeof(sf));
sf.sf_uc.uc_sigmask = *mask;
sf.sf_uc.uc_stack = p->p_sigstk;
sf.sf_uc.uc_stack.ss_flags = (p->p_flag & P_ALTSTACK)
? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
sf.sf_uc.uc_mcontext.mc_onstack = (oonstack) ? 1 : 0;
sf.sf_uc.uc_mcontext.mc_gs = rgs();
bcopy(regs, &sf.sf_uc.uc_mcontext.mc_fs, sizeof(*regs));
/* Allocate space for the signal handler context. */
if ((p->p_flag & P_ALTSTACK) != 0 && !oonstack &&
SIGISMEMBER(psp->ps_sigonstack, sig)) {
sfp = (struct sigframe4 *)(p->p_sigstk.ss_sp +
p->p_sigstk.ss_size - sizeof(struct sigframe4));
#if defined(COMPAT_43) || defined(COMPAT_SUNOS)
p->p_sigstk.ss_flags |= SS_ONSTACK;
#endif
} else
sfp = (struct sigframe4 *)regs->tf_esp - 1;
PROC_UNLOCK(p);
/* Translate the signal if appropriate. */
if (p->p_sysent->sv_sigtbl && sig <= p->p_sysent->sv_sigsize)
sig = p->p_sysent->sv_sigtbl[_SIG_IDX(sig)];
/* Build the argument list for the signal handler. */
sf.sf_signum = sig;
sf.sf_ucontext = (register_t)&sfp->sf_uc;
PROC_LOCK(p);
if (SIGISMEMBER(p->p_sigacts->ps_siginfo, sig)) {
/* Signal handler installed with SA_SIGINFO. */
sf.sf_siginfo = (register_t)&sfp->sf_si;
sf.sf_ahu.sf_action = (__siginfohandler_t *)catcher;
/* Fill in POSIX parts */
sf.sf_si.si_signo = sig;
sf.sf_si.si_code = code;
sf.sf_si.si_addr = (void *)regs->tf_err;
} else {
/* Old FreeBSD-style arguments. */
sf.sf_siginfo = code;
sf.sf_addr = regs->tf_err;
sf.sf_ahu.sf_handler = catcher;
}
PROC_UNLOCK(p);
/*
* If we're a vm86 process, we want to save the segment registers.
* We also change eflags to be our emulated eflags, not the actual
* eflags.
*/
if (regs->tf_eflags & PSL_VM) {
struct trapframe_vm86 *tf = (struct trapframe_vm86 *)regs;
struct vm86_kernel *vm86 = &td->td_pcb->pcb_ext->ext_vm86;
sf.sf_uc.uc_mcontext.mc_gs = tf->tf_vm86_gs;
sf.sf_uc.uc_mcontext.mc_fs = tf->tf_vm86_fs;
sf.sf_uc.uc_mcontext.mc_es = tf->tf_vm86_es;
sf.sf_uc.uc_mcontext.mc_ds = tf->tf_vm86_ds;
if (vm86->vm86_has_vme == 0)
sf.sf_uc.uc_mcontext.mc_eflags =
(tf->tf_eflags & ~(PSL_VIF | PSL_VIP)) |
(vm86->vm86_eflags & (PSL_VIF | PSL_VIP));
/*
* Clear PSL_NT to inhibit T_TSSFLT faults on return from
* syscalls made by the signal handler. This just avoids
* wasting time for our lazy fixup of such faults. PSL_NT
* does nothing in vm86 mode, but vm86 programs can set it
* almost legitimately in probes for old cpu types.
*/
tf->tf_eflags &= ~(PSL_VM | PSL_NT | PSL_VIF | PSL_VIP);
}
/*
* Copy the sigframe out to the user's stack.
*/
if (copyout(&sf, sfp, sizeof(*sfp)) != 0) {
#ifdef DEBUG
printf("process %ld has trashed its stack\n", (long)p->p_pid);
#endif
PROC_LOCK(p);
sigexit(td, SIGILL);
}
regs->tf_esp = (int)sfp;
regs->tf_eip = PS_STRINGS - szfreebsd4_sigcode;
regs->tf_eflags &= ~PSL_T;
regs->tf_cs = _ucodesel;
regs->tf_ds = _udatasel;
regs->tf_es = _udatasel;
regs->tf_fs = _udatasel;
regs->tf_ss = _udatasel;
PROC_LOCK(p);
}
#endif /* COMPAT_FREEBSD4 */
void
sendsig(catcher, sig, mask, code)
sig_t catcher;
int sig;
sigset_t *mask;
u_long code;
{
struct sigframe sf, *sfp;
struct proc *p;
struct thread *td;
struct sigacts *psp;
char *sp;
struct trapframe *regs;
int oonstack;
td = curthread;
p = td->td_proc;
PROC_LOCK_ASSERT(p, MA_OWNED);
psp = p->p_sigacts;
#ifdef COMPAT_FREEBSD4
if (SIGISMEMBER(psp->ps_freebsd4, sig)) {
freebsd4_sendsig(catcher, sig, mask, code);
return;
}
#endif
#ifdef COMPAT_43
if (SIGISMEMBER(psp->ps_osigset, sig)) {
osendsig(catcher, sig, mask, code);
return;
}
#endif
regs = td->td_frame;
oonstack = sigonstack(regs->tf_esp);
/* Save user context. */
bzero(&sf, sizeof(sf));
sf.sf_uc.uc_sigmask = *mask;
sf.sf_uc.uc_stack = p->p_sigstk;
sf.sf_uc.uc_stack.ss_flags = (p->p_flag & P_ALTSTACK)
? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
sf.sf_uc.uc_mcontext.mc_onstack = (oonstack) ? 1 : 0;
sf.sf_uc.uc_mcontext.mc_gs = rgs();
bcopy(regs, &sf.sf_uc.uc_mcontext.mc_fs, sizeof(*regs));
sf.sf_uc.uc_mcontext.mc_len = sizeof(sf.sf_uc.uc_mcontext); /* magic */
get_fpcontext(td, &sf.sf_uc.uc_mcontext);
fpstate_drop(td);
/* Allocate space for the signal handler context. */
if ((p->p_flag & P_ALTSTACK) != 0 && !oonstack &&
SIGISMEMBER(psp->ps_sigonstack, sig)) {
sp = p->p_sigstk.ss_sp +
p->p_sigstk.ss_size - sizeof(struct sigframe);
#if defined(COMPAT_43) || defined(COMPAT_SUNOS)
p->p_sigstk.ss_flags |= SS_ONSTACK;
#endif
} else
sp = (char *)regs->tf_esp - sizeof(struct sigframe);
/* Align to 16 bytes. */
sfp = (struct sigframe *)((unsigned int)sp & ~0xF);
PROC_UNLOCK(p);
/* Translate the signal if appropriate. */
if (p->p_sysent->sv_sigtbl && sig <= p->p_sysent->sv_sigsize)
sig = p->p_sysent->sv_sigtbl[_SIG_IDX(sig)];
/* Build the argument list for the signal handler. */
sf.sf_signum = sig;
sf.sf_ucontext = (register_t)&sfp->sf_uc;
PROC_LOCK(p);
if (SIGISMEMBER(p->p_sigacts->ps_siginfo, sig)) {
/* Signal handler installed with SA_SIGINFO. */
sf.sf_siginfo = (register_t)&sfp->sf_si;
sf.sf_ahu.sf_action = (__siginfohandler_t *)catcher;
/* Fill in POSIX parts */
sf.sf_si.si_signo = sig;
sf.sf_si.si_code = code;
sf.sf_si.si_addr = (void *)regs->tf_err;
} else {
/* Old FreeBSD-style arguments. */
sf.sf_siginfo = code;
sf.sf_addr = regs->tf_err;
sf.sf_ahu.sf_handler = catcher;
}
PROC_UNLOCK(p);
/*
* If we're a vm86 process, we want to save the segment registers.
* We also change eflags to be our emulated eflags, not the actual
* eflags.
*/
if (regs->tf_eflags & PSL_VM) {
struct trapframe_vm86 *tf = (struct trapframe_vm86 *)regs;
struct vm86_kernel *vm86 = &td->td_pcb->pcb_ext->ext_vm86;
sf.sf_uc.uc_mcontext.mc_gs = tf->tf_vm86_gs;
sf.sf_uc.uc_mcontext.mc_fs = tf->tf_vm86_fs;
sf.sf_uc.uc_mcontext.mc_es = tf->tf_vm86_es;
sf.sf_uc.uc_mcontext.mc_ds = tf->tf_vm86_ds;
if (vm86->vm86_has_vme == 0)
sf.sf_uc.uc_mcontext.mc_eflags =
(tf->tf_eflags & ~(PSL_VIF | PSL_VIP)) |
(vm86->vm86_eflags & (PSL_VIF | PSL_VIP));
/*
* Clear PSL_NT to inhibit T_TSSFLT faults on return from
* syscalls made by the signal handler. This just avoids
* wasting time for our lazy fixup of such faults. PSL_NT
* does nothing in vm86 mode, but vm86 programs can set it
* almost legitimately in probes for old cpu types.
*/
tf->tf_eflags &= ~(PSL_VM | PSL_NT | PSL_VIF | PSL_VIP);
}
/*
* Copy the sigframe out to the user's stack.
*/
if (copyout(&sf, sfp, sizeof(*sfp)) != 0) {
#ifdef DEBUG
printf("process %ld has trashed its stack\n", (long)p->p_pid);
#endif
PROC_LOCK(p);
sigexit(td, SIGILL);
}
regs->tf_esp = (int)sfp;
regs->tf_eip = PS_STRINGS - *(p->p_sysent->sv_szsigcode);
regs->tf_eflags &= ~PSL_T;
regs->tf_cs = _ucodesel;
regs->tf_ds = _udatasel;
regs->tf_es = _udatasel;
regs->tf_fs = _udatasel;
regs->tf_ss = _udatasel;
PROC_LOCK(p);
}
/*
* System call to cleanup state after a signal
* has been taken. Reset signal mask and
* stack state from context left by sendsig (above).
* Return to previous pc and psl as specified by
* context left by sendsig. Check carefully to
* make sure that the user has not modified the
* state to gain improper privileges.
*
* MPSAFE
*/
#ifdef COMPAT_43
int
osigreturn(td, uap)
struct thread *td;
struct osigreturn_args /* {
struct osigcontext *sigcntxp;
} */ *uap;
{
struct osigcontext sc;
struct trapframe *regs;
struct osigcontext *scp;
struct proc *p = td->td_proc;
int eflags, error;
regs = td->td_frame;
error = copyin(uap->sigcntxp, &sc, sizeof(sc));
if (error != 0)
return (error);
scp = &sc;
eflags = scp->sc_ps;
if (eflags & PSL_VM) {
struct trapframe_vm86 *tf = (struct trapframe_vm86 *)regs;
struct vm86_kernel *vm86;
/*
* if pcb_ext == 0 or vm86_inited == 0, the user hasn't
* set up the vm86 area, and we can't enter vm86 mode.
*/
if (td->td_pcb->pcb_ext == 0)
return (EINVAL);
vm86 = &td->td_pcb->pcb_ext->ext_vm86;
if (vm86->vm86_inited == 0)
return (EINVAL);
/* Go back to user mode if both flags are set. */
if ((eflags & PSL_VIP) && (eflags & PSL_VIF))
trapsignal(p, SIGBUS, 0);
if (vm86->vm86_has_vme) {
eflags = (tf->tf_eflags & ~VME_USERCHANGE) |
(eflags & VME_USERCHANGE) | PSL_VM;
} else {
vm86->vm86_eflags = eflags; /* save VIF, VIP */
eflags = (tf->tf_eflags & ~VM_USERCHANGE) |
(eflags & VM_USERCHANGE) | PSL_VM;
}
tf->tf_vm86_ds = scp->sc_ds;
tf->tf_vm86_es = scp->sc_es;
tf->tf_vm86_fs = scp->sc_fs;
tf->tf_vm86_gs = scp->sc_gs;
tf->tf_ds = _udatasel;
tf->tf_es = _udatasel;
tf->tf_fs = _udatasel;
} else {
/*
* Don't allow users to change privileged or reserved flags.
*/
/*
* XXX do allow users to change the privileged flag PSL_RF.
* The cpu sets PSL_RF in tf_eflags for faults. Debuggers
* should sometimes set it there too. tf_eflags is kept in
* the signal context during signal handling and there is no
* other place to remember it, so the PSL_RF bit may be
* corrupted by the signal handler without us knowing.
* Corruption of the PSL_RF bit at worst causes one more or
* one less debugger trap, so allowing it is fairly harmless.
*/
if (!EFL_SECURE(eflags & ~PSL_RF, regs->tf_eflags & ~PSL_RF)) {
return (EINVAL);
}
/*
* Don't allow users to load a valid privileged %cs. Let the
* hardware check for invalid selectors, excess privilege in
* other selectors, invalid %eip's and invalid %esp's.
*/
if (!CS_SECURE(scp->sc_cs)) {
trapsignal(p, SIGBUS, T_PROTFLT);
return (EINVAL);
}
regs->tf_ds = scp->sc_ds;
regs->tf_es = scp->sc_es;
regs->tf_fs = scp->sc_fs;
}
/* Restore remaining registers. */
regs->tf_eax = scp->sc_eax;
regs->tf_ebx = scp->sc_ebx;
regs->tf_ecx = scp->sc_ecx;
regs->tf_edx = scp->sc_edx;
regs->tf_esi = scp->sc_esi;
regs->tf_edi = scp->sc_edi;
regs->tf_cs = scp->sc_cs;
regs->tf_ss = scp->sc_ss;
regs->tf_isp = scp->sc_isp;
regs->tf_ebp = scp->sc_fp;
regs->tf_esp = scp->sc_sp;
regs->tf_eip = scp->sc_pc;
regs->tf_eflags = eflags;
PROC_LOCK(p);
#if defined(COMPAT_43) || defined(COMPAT_SUNOS)
if (scp->sc_onstack & 1)
p->p_sigstk.ss_flags |= SS_ONSTACK;
else
p->p_sigstk.ss_flags &= ~SS_ONSTACK;
#endif
SIGSETOLD(p->p_sigmask, scp->sc_mask);
SIG_CANTMASK(p->p_sigmask);
signotify(p);
PROC_UNLOCK(p);
return (EJUSTRETURN);
}
#endif /* COMPAT_43 */
#ifdef COMPAT_FREEBSD4
/*
* MPSAFE
*/
int
freebsd4_sigreturn(td, uap)
struct thread *td;
struct freebsd4_sigreturn_args /* {
const ucontext4 *sigcntxp;
} */ *uap;
{
struct ucontext4 uc;
struct proc *p = td->td_proc;
struct trapframe *regs;
const struct ucontext4 *ucp;
int cs, eflags, error;
error = copyin(uap->sigcntxp, &uc, sizeof(uc));
if (error != 0)
return (error);
ucp = &uc;
regs = td->td_frame;
eflags = ucp->uc_mcontext.mc_eflags;
if (eflags & PSL_VM) {
struct trapframe_vm86 *tf = (struct trapframe_vm86 *)regs;
struct vm86_kernel *vm86;
/*
* if pcb_ext == 0 or vm86_inited == 0, the user hasn't
* set up the vm86 area, and we can't enter vm86 mode.
*/
if (td->td_pcb->pcb_ext == 0)
return (EINVAL);
vm86 = &td->td_pcb->pcb_ext->ext_vm86;
if (vm86->vm86_inited == 0)
return (EINVAL);
/* Go back to user mode if both flags are set. */
if ((eflags & PSL_VIP) && (eflags & PSL_VIF))
trapsignal(p, SIGBUS, 0);
if (vm86->vm86_has_vme) {
eflags = (tf->tf_eflags & ~VME_USERCHANGE) |
(eflags & VME_USERCHANGE) | PSL_VM;
} else {
vm86->vm86_eflags = eflags; /* save VIF, VIP */
eflags = (tf->tf_eflags & ~VM_USERCHANGE) |
(eflags & VM_USERCHANGE) | PSL_VM;
}
bcopy(&ucp->uc_mcontext.mc_fs, tf, sizeof(struct trapframe));
tf->tf_eflags = eflags;
tf->tf_vm86_ds = tf->tf_ds;
tf->tf_vm86_es = tf->tf_es;
tf->tf_vm86_fs = tf->tf_fs;
tf->tf_vm86_gs = ucp->uc_mcontext.mc_gs;
tf->tf_ds = _udatasel;
tf->tf_es = _udatasel;
tf->tf_fs = _udatasel;
} else {
/*
* Don't allow users to change privileged or reserved flags.
*/
/*
* XXX do allow users to change the privileged flag PSL_RF.
* The cpu sets PSL_RF in tf_eflags for faults. Debuggers
* should sometimes set it there too. tf_eflags is kept in
* the signal context during signal handling and there is no
* other place to remember it, so the PSL_RF bit may be
* corrupted by the signal handler without us knowing.
* Corruption of the PSL_RF bit at worst causes one more or
* one less debugger trap, so allowing it is fairly harmless.
*/
if (!EFL_SECURE(eflags & ~PSL_RF, regs->tf_eflags & ~PSL_RF)) {
printf("freebsd4_sigreturn: eflags = 0x%x\n", eflags);
return (EINVAL);
}
/*
* Don't allow users to load a valid privileged %cs. Let the
* hardware check for invalid selectors, excess privilege in
* other selectors, invalid %eip's and invalid %esp's.
*/
cs = ucp->uc_mcontext.mc_cs;
if (!CS_SECURE(cs)) {
printf("freebsd4_sigreturn: cs = 0x%x\n", cs);
trapsignal(p, SIGBUS, T_PROTFLT);
return (EINVAL);
}
bcopy(&ucp->uc_mcontext.mc_fs, regs, sizeof(*regs));
}
PROC_LOCK(p);
#if defined(COMPAT_43) || defined(COMPAT_SUNOS)
if (ucp->uc_mcontext.mc_onstack & 1)
p->p_sigstk.ss_flags |= SS_ONSTACK;
else
p->p_sigstk.ss_flags &= ~SS_ONSTACK;
#endif
p->p_sigmask = ucp->uc_sigmask;
SIG_CANTMASK(p->p_sigmask);
signotify(p);
PROC_UNLOCK(p);
return (EJUSTRETURN);
}
#endif /* COMPAT_FREEBSD4 */
/*
* MPSAFE
*/
int
sigreturn(td, uap)
struct thread *td;
struct sigreturn_args /* {
const __ucontext *sigcntxp;
} */ *uap;
{
ucontext_t uc;
struct proc *p = td->td_proc;
struct trapframe *regs;
const ucontext_t *ucp;
int cs, eflags, error, ret;
error = copyin(uap->sigcntxp, &uc, sizeof(uc));
if (error != 0)
return (error);
ucp = &uc;
regs = td->td_frame;
eflags = ucp->uc_mcontext.mc_eflags;
if (eflags & PSL_VM) {
struct trapframe_vm86 *tf = (struct trapframe_vm86 *)regs;
struct vm86_kernel *vm86;
/*
* if pcb_ext == 0 or vm86_inited == 0, the user hasn't
* set up the vm86 area, and we can't enter vm86 mode.
*/
if (td->td_pcb->pcb_ext == 0)
return (EINVAL);
vm86 = &td->td_pcb->pcb_ext->ext_vm86;
if (vm86->vm86_inited == 0)
return (EINVAL);
/* Go back to user mode if both flags are set. */
if ((eflags & PSL_VIP) && (eflags & PSL_VIF))
trapsignal(p, SIGBUS, 0);
if (vm86->vm86_has_vme) {
eflags = (tf->tf_eflags & ~VME_USERCHANGE) |
(eflags & VME_USERCHANGE) | PSL_VM;
} else {
vm86->vm86_eflags = eflags; /* save VIF, VIP */
eflags = (tf->tf_eflags & ~VM_USERCHANGE) |
(eflags & VM_USERCHANGE) | PSL_VM;
}
bcopy(&ucp->uc_mcontext.mc_fs, tf, sizeof(struct trapframe));
tf->tf_eflags = eflags;
tf->tf_vm86_ds = tf->tf_ds;
tf->tf_vm86_es = tf->tf_es;
tf->tf_vm86_fs = tf->tf_fs;
tf->tf_vm86_gs = ucp->uc_mcontext.mc_gs;
tf->tf_ds = _udatasel;
tf->tf_es = _udatasel;
tf->tf_fs = _udatasel;
} else {
/*
* Don't allow users to change privileged or reserved flags.
*/
/*
* XXX do allow users to change the privileged flag PSL_RF.
* The cpu sets PSL_RF in tf_eflags for faults. Debuggers
* should sometimes set it there too. tf_eflags is kept in
* the signal context during signal handling and there is no
* other place to remember it, so the PSL_RF bit may be
* corrupted by the signal handler without us knowing.
* Corruption of the PSL_RF bit at worst causes one more or
* one less debugger trap, so allowing it is fairly harmless.
*/
if (!EFL_SECURE(eflags & ~PSL_RF, regs->tf_eflags & ~PSL_RF)) {
printf("sigreturn: eflags = 0x%x\n", eflags);
return (EINVAL);
}
/*
* Don't allow users to load a valid privileged %cs. Let the
* hardware check for invalid selectors, excess privilege in
* other selectors, invalid %eip's and invalid %esp's.
*/
cs = ucp->uc_mcontext.mc_cs;
if (!CS_SECURE(cs)) {
printf("sigreturn: cs = 0x%x\n", cs);
trapsignal(p, SIGBUS, T_PROTFLT);
return (EINVAL);
}
ret = set_fpcontext(td, &ucp->uc_mcontext);
if (ret != 0)
return (ret);
bcopy(&ucp->uc_mcontext.mc_fs, regs, sizeof(*regs));
}
PROC_LOCK(p);
#if defined(COMPAT_43) || defined(COMPAT_SUNOS)
if (ucp->uc_mcontext.mc_onstack & 1)
p->p_sigstk.ss_flags |= SS_ONSTACK;
else
p->p_sigstk.ss_flags &= ~SS_ONSTACK;
#endif
p->p_sigmask = ucp->uc_sigmask;
SIG_CANTMASK(p->p_sigmask);
signotify(p);
PROC_UNLOCK(p);
return (EJUSTRETURN);
}
/*
* Machine dependent boot() routine
*
* I haven't seen anything to put here yet
* Possibly some stuff might be grafted back here from boot()
*/
void
cpu_boot(int howto)
{
}
/*
* Shutdown the CPU as much as possible
*/
void
cpu_halt(void)
{
for (;;)
__asm__ ("hlt");
}
/*
* Hook to idle the CPU when possible. In the SMP case we default to
* off because a halted cpu will not currently pick up a new thread in the
* run queue until the next timer tick. If turned on this will result in
* approximately a 4.2% loss in real time performance in buildworld tests
* (but improves user and sys times oddly enough), and saves approximately
* 5% in power consumption on an idle machine (tests w/2xCPU 1.1GHz P3).
*
* XXX we need to have a cpu mask of idle cpus and generate an IPI or
* otherwise generate some sort of interrupt to wake up cpus sitting in HLT.
* Then we can have our cake and eat it too.
*/
#ifdef SMP
static int cpu_idle_hlt = 0;
#else
static int cpu_idle_hlt = 1;
#endif
SYSCTL_INT(_machdep, OID_AUTO, cpu_idle_hlt, CTLFLAG_RW,
&cpu_idle_hlt, 0, "Idle loop HLT enable");
/*
* Note that we have to be careful here to avoid a race between checking
* sched_runnable() and actually halting. If we don't do this, we may waste
* the time between calling hlt and the next interrupt even though there
* is a runnable process.
*/
void
cpu_idle(void)
{
if (cpu_idle_hlt) {
disable_intr();
if (sched_runnable()) {
enable_intr();
} else {
/*
* we must absolutely guarentee that hlt is the
* absolute next instruction after sti or we
* introduce a timing window.
*/
__asm __volatile("sti; hlt");
}
}
}
/*
* Clear registers on exec
*/
void
exec_setregs(td, entry, stack, ps_strings)
struct thread *td;
u_long entry;
u_long stack;
u_long ps_strings;
{
struct trapframe *regs = td->td_frame;
struct pcb *pcb = td->td_pcb;
/* Reset pc->pcb_gs and %gs before possibly invalidating it. */
pcb->pcb_gs = _udatasel;
load_gs(_udatasel);
if (td->td_proc->p_md.md_ldt)
user_ldt_free(td);
bzero((char *)regs, sizeof(struct trapframe));
regs->tf_eip = entry;
regs->tf_esp = stack;
regs->tf_eflags = PSL_USER | (regs->tf_eflags & PSL_T);
regs->tf_ss = _udatasel;
regs->tf_ds = _udatasel;
regs->tf_es = _udatasel;
regs->tf_fs = _udatasel;
regs->tf_cs = _ucodesel;
/* PS_STRINGS value for BSD/OS binaries. It is 0 for non-BSD/OS. */
regs->tf_ebx = ps_strings;
/*
* Reset the hardware debug registers if they were in use.
* They won't have any meaning for the newly exec'd process.
*/
if (pcb->pcb_flags & PCB_DBREGS) {
pcb->pcb_dr0 = 0;
pcb->pcb_dr1 = 0;
pcb->pcb_dr2 = 0;
pcb->pcb_dr3 = 0;
pcb->pcb_dr6 = 0;
pcb->pcb_dr7 = 0;
if (pcb == PCPU_GET(curpcb)) {
/*
* Clear the debug registers on the running
* CPU, otherwise they will end up affecting
* the next process we switch to.
*/
reset_dbregs();
}
pcb->pcb_flags &= ~PCB_DBREGS;
}
/*
* Initialize the math emulator (if any) for the current process.
* Actually, just clear the bit that says that the emulator has
* been initialized. Initialization is delayed until the process
* traps to the emulator (if it is done at all) mainly because
* emulators don't provide an entry point for initialization.
*/
td->td_pcb->pcb_flags &= ~FP_SOFTFP;
/*
* Arrange to trap the next npx or `fwait' instruction (see npx.c
* for why fwait must be trapped at least if there is an npx or an
* emulator). This is mainly to handle the case where npx0 is not
* configured, since the npx routines normally set up the trap
* otherwise. It should be done only at boot time, but doing it
* here allows modifying `npx_exists' for testing the emulator on
* systems with an npx.
*/
load_cr0(rcr0() | CR0_MP | CR0_TS);
/* Initialize the npx (if any) for the current process. */
/*
* XXX the above load_cr0() also initializes it and is a layering
* violation if NPX is configured. It drops the npx partially
* and this would be fatal if we were interrupted now, and decided
* to force the state to the pcb, and checked the invariant
* (CR0_TS clear) if and only if PCPU_GET(fpcurthread) != NULL).
* ALL of this can happen except the check. The check used to
* happen and be fatal later when we didn't complete the drop
* before returning to user mode. This should be fixed properly
* soon.
*/
fpstate_drop(td);
/*
* XXX - Linux emulator
* Make sure sure edx is 0x0 on entry. Linux binaries depend
* on it.
*/
td->td_retval[1] = 0;
}
void
cpu_setregs(void)
{
unsigned int cr0;
cr0 = rcr0();
#ifdef SMP
cr0 |= CR0_NE; /* Done by npxinit() */
#endif
cr0 |= CR0_MP | CR0_TS; /* Done at every execve() too. */
#ifndef I386_CPU
cr0 |= CR0_WP | CR0_AM;
#endif
load_cr0(cr0);
load_gs(_udatasel);
}
static int
sysctl_machdep_adjkerntz(SYSCTL_HANDLER_ARGS)
{
int error;
error = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2,
req);
if (!error && req->newptr)
resettodr();
return (error);
}
SYSCTL_PROC(_machdep, CPU_ADJKERNTZ, adjkerntz, CTLTYPE_INT|CTLFLAG_RW,
&adjkerntz, 0, sysctl_machdep_adjkerntz, "I", "");
SYSCTL_INT(_machdep, CPU_DISRTCSET, disable_rtc_set,
CTLFLAG_RW, &disable_rtc_set, 0, "");
SYSCTL_STRUCT(_machdep, CPU_BOOTINFO, bootinfo,
CTLFLAG_RD, &bootinfo, bootinfo, "");
SYSCTL_INT(_machdep, CPU_WALLCLOCK, wall_cmos_clock,
CTLFLAG_RW, &wall_cmos_clock, 0, "");
u_long bootdev; /* not a dev_t - encoding is different */
SYSCTL_ULONG(_machdep, OID_AUTO, guessed_bootdev,
CTLFLAG_RD, &bootdev, 0, "Maybe the Boot device (not in dev_t format)");
/*
* Initialize 386 and configure to run kernel
*/
/*
* Initialize segments & interrupt table
*/
int _default_ldt;
union descriptor gdt[NGDT * MAXCPU]; /* global descriptor table */
static struct gate_descriptor idt0[NIDT];
struct gate_descriptor *idt = &idt0[0]; /* interrupt descriptor table */
union descriptor ldt[NLDT]; /* local descriptor table */
#ifdef SMP
/* table descriptors - used to load tables by microp */
struct region_descriptor r_gdt, r_idt;
#endif
int private_tss; /* flag indicating private tss */
#if defined(I586_CPU) && !defined(NO_F00F_HACK)
extern int has_f00f_bug;
#endif
static struct i386tss dblfault_tss;
static char dblfault_stack[PAGE_SIZE];
extern struct user *proc0uarea;
extern vm_offset_t proc0kstack;
/* software prototypes -- in more palatable form */
struct soft_segment_descriptor gdt_segs[] = {
/* GNULL_SEL 0 Null Descriptor */
{ 0x0, /* segment base address */
0x0, /* length */
0, /* segment type */
0, /* segment descriptor priority level */
0, /* segment descriptor present */
0, 0,
0, /* default 32 vs 16 bit size */
0 /* limit granularity (byte/page units)*/ },
/* GCODE_SEL 1 Code Descriptor for kernel */
{ 0x0, /* segment base address */
0xfffff, /* length - all address space */
SDT_MEMERA, /* segment type */
0, /* segment descriptor priority level */
1, /* segment descriptor present */
0, 0,
1, /* default 32 vs 16 bit size */
1 /* limit granularity (byte/page units)*/ },
/* GDATA_SEL 2 Data Descriptor for kernel */
{ 0x0, /* segment base address */
0xfffff, /* length - all address space */
SDT_MEMRWA, /* segment type */
0, /* segment descriptor priority level */
1, /* segment descriptor present */
0, 0,
1, /* default 32 vs 16 bit size */
1 /* limit granularity (byte/page units)*/ },
/* GPRIV_SEL 3 SMP Per-Processor Private Data Descriptor */
{ 0x0, /* segment base address */
0xfffff, /* length - all address space */
SDT_MEMRWA, /* segment type */
0, /* segment descriptor priority level */
1, /* segment descriptor present */
0, 0,
1, /* default 32 vs 16 bit size */
1 /* limit granularity (byte/page units)*/ },
/* GPROC0_SEL 4 Proc 0 Tss Descriptor */
{
0x0, /* segment base address */
sizeof(struct i386tss)-1,/* length - all address space */
SDT_SYS386TSS, /* segment type */
0, /* segment descriptor priority level */
1, /* segment descriptor present */
0, 0,
0, /* unused - default 32 vs 16 bit size */
0 /* limit granularity (byte/page units)*/ },
/* GLDT_SEL 5 LDT Descriptor */
{ (int) ldt, /* segment base address */
sizeof(ldt)-1, /* length - all address space */
SDT_SYSLDT, /* segment type */
SEL_UPL, /* segment descriptor priority level */
1, /* segment descriptor present */
0, 0,
0, /* unused - default 32 vs 16 bit size */
0 /* limit granularity (byte/page units)*/ },
/* GUSERLDT_SEL 6 User LDT Descriptor per process */
{ (int) ldt, /* segment base address */
(512 * sizeof(union descriptor)-1), /* length */
SDT_SYSLDT, /* segment type */
0, /* segment descriptor priority level */
1, /* segment descriptor present */
0, 0,
0, /* unused - default 32 vs 16 bit size */
0 /* limit granularity (byte/page units)*/ },
/* GTGATE_SEL 7 Null Descriptor - Placeholder */
{ 0x0, /* segment base address */
0x0, /* length - all address space */
0, /* segment type */
0, /* segment descriptor priority level */
0, /* segment descriptor present */
0, 0,
0, /* default 32 vs 16 bit size */
0 /* limit granularity (byte/page units)*/ },
/* GBIOSLOWMEM_SEL 8 BIOS access to realmode segment 0x40, must be #8 in GDT */
{ 0x400, /* segment base address */
0xfffff, /* length */
SDT_MEMRWA, /* segment type */
0, /* segment descriptor priority level */
1, /* segment descriptor present */
0, 0,
1, /* default 32 vs 16 bit size */
1 /* limit granularity (byte/page units)*/ },
/* GPANIC_SEL 9 Panic Tss Descriptor */
{ (int) &dblfault_tss, /* segment base address */
sizeof(struct i386tss)-1,/* length - all address space */
SDT_SYS386TSS, /* segment type */
0, /* segment descriptor priority level */
1, /* segment descriptor present */
0, 0,
0, /* unused - default 32 vs 16 bit size */
0 /* limit granularity (byte/page units)*/ },
/* GBIOSCODE32_SEL 10 BIOS 32-bit interface (32bit Code) */
{ 0, /* segment base address (overwritten) */
0xfffff, /* length */
SDT_MEMERA, /* segment type */
0, /* segment descriptor priority level */
1, /* segment descriptor present */
0, 0,
0, /* default 32 vs 16 bit size */
1 /* limit granularity (byte/page units)*/ },
/* GBIOSCODE16_SEL 11 BIOS 32-bit interface (16bit Code) */
{ 0, /* segment base address (overwritten) */
0xfffff, /* length */
SDT_MEMERA, /* segment type */
0, /* segment descriptor priority level */
1, /* segment descriptor present */
0, 0,
0, /* default 32 vs 16 bit size */
1 /* limit granularity (byte/page units)*/ },
/* GBIOSDATA_SEL 12 BIOS 32-bit interface (Data) */
{ 0, /* segment base address (overwritten) */
0xfffff, /* length */
SDT_MEMRWA, /* segment type */
0, /* segment descriptor priority level */
1, /* segment descriptor present */
0, 0,
1, /* default 32 vs 16 bit size */
1 /* limit granularity (byte/page units)*/ },
/* GBIOSUTIL_SEL 13 BIOS 16-bit interface (Utility) */
{ 0, /* segment base address (overwritten) */
0xfffff, /* length */
SDT_MEMRWA, /* segment type */
0, /* segment descriptor priority level */
1, /* segment descriptor present */
0, 0,
0, /* default 32 vs 16 bit size */
1 /* limit granularity (byte/page units)*/ },
/* GBIOSARGS_SEL 14 BIOS 16-bit interface (Arguments) */
{ 0, /* segment base address (overwritten) */
0xfffff, /* length */
SDT_MEMRWA, /* segment type */
0, /* segment descriptor priority level */
1, /* segment descriptor present */
0, 0,
0, /* default 32 vs 16 bit size */
1 /* limit granularity (byte/page units)*/ },
};
static struct soft_segment_descriptor ldt_segs[] = {
/* Null Descriptor - overwritten by call gate */
{ 0x0, /* segment base address */
0x0, /* length - all address space */
0, /* segment type */
0, /* segment descriptor priority level */
0, /* segment descriptor present */
0, 0,
0, /* default 32 vs 16 bit size */
0 /* limit granularity (byte/page units)*/ },
/* Null Descriptor - overwritten by call gate */
{ 0x0, /* segment base address */
0x0, /* length - all address space */
0, /* segment type */
0, /* segment descriptor priority level */
0, /* segment descriptor present */
0, 0,
0, /* default 32 vs 16 bit size */
0 /* limit granularity (byte/page units)*/ },
/* Null Descriptor - overwritten by call gate */
{ 0x0, /* segment base address */
0x0, /* length - all address space */
0, /* segment type */
0, /* segment descriptor priority level */
0, /* segment descriptor present */
0, 0,
0, /* default 32 vs 16 bit size */
0 /* limit granularity (byte/page units)*/ },
/* Code Descriptor for user */
{ 0x0, /* segment base address */
0xfffff, /* length - all address space */
SDT_MEMERA, /* segment type */
SEL_UPL, /* segment descriptor priority level */
1, /* segment descriptor present */
0, 0,
1, /* default 32 vs 16 bit size */
1 /* limit granularity (byte/page units)*/ },
/* Null Descriptor - overwritten by call gate */
{ 0x0, /* segment base address */
0x0, /* length - all address space */
0, /* segment type */
0, /* segment descriptor priority level */
0, /* segment descriptor present */
0, 0,
0, /* default 32 vs 16 bit size */
0 /* limit granularity (byte/page units)*/ },
/* Data Descriptor for user */
{ 0x0, /* segment base address */
0xfffff, /* length - all address space */
SDT_MEMRWA, /* segment type */
SEL_UPL, /* segment descriptor priority level */
1, /* segment descriptor present */
0, 0,
1, /* default 32 vs 16 bit size */
1 /* limit granularity (byte/page units)*/ },
};
void
setidt(idx, func, typ, dpl, selec)
int idx;
inthand_t *func;
int typ;
int dpl;
int selec;
{
struct gate_descriptor *ip;
ip = idt + idx;
ip->gd_looffset = (int)func;
ip->gd_selector = selec;
ip->gd_stkcpy = 0;
ip->gd_xx = 0;
ip->gd_type = typ;
ip->gd_dpl = dpl;
ip->gd_p = 1;
ip->gd_hioffset = ((int)func)>>16 ;
}
#define IDTVEC(name) __CONCAT(X,name)
extern inthand_t
IDTVEC(div), IDTVEC(dbg), IDTVEC(nmi), IDTVEC(bpt), IDTVEC(ofl),
IDTVEC(bnd), IDTVEC(ill), IDTVEC(dna), IDTVEC(fpusegm),
IDTVEC(tss), IDTVEC(missing), IDTVEC(stk), IDTVEC(prot),
IDTVEC(page), IDTVEC(mchk), IDTVEC(rsvd), IDTVEC(fpu), IDTVEC(align),
IDTVEC(xmm), IDTVEC(lcall_syscall), IDTVEC(int0x80_syscall);
void
sdtossd(sd, ssd)
struct segment_descriptor *sd;
struct soft_segment_descriptor *ssd;
{
ssd->ssd_base = (sd->sd_hibase << 24) | sd->sd_lobase;
ssd->ssd_limit = (sd->sd_hilimit << 16) | sd->sd_lolimit;
ssd->ssd_type = sd->sd_type;
ssd->ssd_dpl = sd->sd_dpl;
ssd->ssd_p = sd->sd_p;
ssd->ssd_def32 = sd->sd_def32;
ssd->ssd_gran = sd->sd_gran;
}
#define PHYSMAP_SIZE (2 * 8)
/*
* Populate the (physmap) array with base/bound pairs describing the
* available physical memory in the system, then test this memory and
* build the phys_avail array describing the actually-available memory.
*
* If we cannot accurately determine the physical memory map, then use
* value from the 0xE801 call, and failing that, the RTC.
*
* Total memory size may be set by the kernel environment variable
* hw.physmem or the compile-time define MAXMEM.
*/
static void
getmemsize(int first)
{
#ifdef PC98
int i, physmap_idx, pa_indx, pg_n;
u_int basemem, extmem, under16;
vm_offset_t pa, physmap[PHYSMAP_SIZE];
pt_entry_t *pte;
char *cp;
#else
int i, physmap_idx, pa_indx;
u_int basemem, extmem;
struct vm86frame vmf;
struct vm86context vmc;
vm_offset_t pa, physmap[PHYSMAP_SIZE];
pt_entry_t *pte;
char *cp;
struct bios_smap *smap;
#endif
#ifdef PC98
/* XXX - some of EPSON machines can't use PG_N */
pg_n = PG_N;
if (pc98_machine_type & M_EPSON_PC98) {
switch (epson_machine_id) {
#ifdef WB_CACHE
default:
#endif
case 0x34: /* PC-486HX */
case 0x35: /* PC-486HG */
case 0x3B: /* PC-486HA */
pg_n = 0;
break;
}
}
bzero(physmap, sizeof(physmap));
/*
* Perform "base memory" related probes & setup
*/
under16 = pc98_getmemsize(&basemem, &extmem);
if (basemem > 640) {
printf("Preposterous BIOS basemem of %uK, truncating to 640K\n",
basemem);
basemem = 640;
}
/*
* XXX if biosbasemem is now < 640, there is a `hole'
* between the end of base memory and the start of
* ISA memory. The hole may be empty or it may
* contain BIOS code or data. Map it read/write so
* that the BIOS can write to it. (Memory from 0 to
* the physical end of the kernel is mapped read-only
* to begin with and then parts of it are remapped.
* The parts that aren't remapped form holes that
* remain read-only and are unused by the kernel.
* The base memory area is below the physical end of
* the kernel and right now forms a read-only hole.
* The part of it from PAGE_SIZE to
* (trunc_page(biosbasemem * 1024) - 1) will be
* remapped and used by the kernel later.)
*
* This code is similar to the code used in
* pmap_mapdev, but since no memory needs to be
* allocated we simply change the mapping.
*/
for (pa = trunc_page(basemem * 1024);
pa < ISA_HOLE_START; pa += PAGE_SIZE)
pmap_kenter(KERNBASE + pa, pa);
/*
* if basemem != 640, map pages r/w into vm86 page table so
* that the bios can scribble on it.
*/
pte = (pt_entry_t *)vm86paddr;
for (i = basemem / 4; i < 160; i++)
pte[i] = (i << PAGE_SHIFT) | PG_V | PG_RW | PG_U;
#else /* PC98 */
bzero(&vmf, sizeof(struct vm86frame));
bzero(physmap, sizeof(physmap));
basemem = 0;
/*
* map page 1 R/W into the kernel page table so we can use it
* as a buffer. The kernel will unmap this page later.
*/
pmap_kenter(KERNBASE + (1 << PAGE_SHIFT), 1);
/*
* get memory map with INT 15:E820
*/
vmc.npages = 0;
smap = (void *)vm86_addpage(&vmc, 1, KERNBASE + (1 << PAGE_SHIFT));
vm86_getptr(&vmc, (vm_offset_t)smap, &vmf.vmf_es, &vmf.vmf_di);
physmap_idx = 0;
vmf.vmf_ebx = 0;
do {
vmf.vmf_eax = 0xE820;
vmf.vmf_edx = SMAP_SIG;
vmf.vmf_ecx = sizeof(struct bios_smap);
i = vm86_datacall(0x15, &vmf, &vmc);
if (i || vmf.vmf_eax != SMAP_SIG)
break;
if (boothowto & RB_VERBOSE)
printf("SMAP type=%02x base=%08x %08x len=%08x %08x\n",
smap->type,
*(u_int32_t *)((char *)&smap->base + 4),
(u_int32_t)smap->base,
*(u_int32_t *)((char *)&smap->length + 4),
(u_int32_t)smap->length);
if (smap->type != 0x01)
goto next_run;
if (smap->length == 0)
goto next_run;
if (smap->base >= 0xffffffff) {
printf("%uK of memory above 4GB ignored\n",
(u_int)(smap->length / 1024));
goto next_run;
}
for (i = 0; i <= physmap_idx; i += 2) {
if (smap->base < physmap[i + 1]) {
if (boothowto & RB_VERBOSE)
printf(
"Overlapping or non-montonic memory region, ignoring second region\n");
goto next_run;
}
}
if (smap->base == physmap[physmap_idx + 1]) {
physmap[physmap_idx + 1] += smap->length;
goto next_run;
}
physmap_idx += 2;
if (physmap_idx == PHYSMAP_SIZE) {
printf(
"Too many segments in the physical address map, giving up\n");
break;
}
physmap[physmap_idx] = smap->base;
physmap[physmap_idx + 1] = smap->base + smap->length;
next_run: ;
} while (vmf.vmf_ebx != 0);
/*
* Perform "base memory" related probes & setup
*/
for (i = 0; i <= physmap_idx; i += 2) {
if (physmap[i] == 0x00000000) {
basemem = physmap[i + 1] / 1024;
break;
}
}
/* Fall back to the old compatibility function for base memory */
if (basemem == 0) {
vm86_intcall(0x12, &vmf);
basemem = vmf.vmf_ax;
}
if (basemem > 640) {
printf("Preposterous BIOS basemem of %uK, truncating to 640K\n",
basemem);
basemem = 640;
}
/*
* XXX if biosbasemem is now < 640, there is a `hole'
* between the end of base memory and the start of
* ISA memory. The hole may be empty or it may
* contain BIOS code or data. Map it read/write so
* that the BIOS can write to it. (Memory from 0 to
* the physical end of the kernel is mapped read-only
* to begin with and then parts of it are remapped.
* The parts that aren't remapped form holes that
* remain read-only and are unused by the kernel.
* The base memory area is below the physical end of
* the kernel and right now forms a read-only hole.
* The part of it from PAGE_SIZE to
* (trunc_page(biosbasemem * 1024) - 1) will be
* remapped and used by the kernel later.)
*
* This code is similar to the code used in
* pmap_mapdev, but since no memory needs to be
* allocated we simply change the mapping.
*/
for (pa = trunc_page(basemem * 1024);
pa < ISA_HOLE_START; pa += PAGE_SIZE)
pmap_kenter(KERNBASE + pa, pa);
/*
* if basemem != 640, map pages r/w into vm86 page table so
* that the bios can scribble on it.
*/
pte = (pt_entry_t *)vm86paddr;
for (i = basemem / 4; i < 160; i++)
pte[i] = (i << PAGE_SHIFT) | PG_V | PG_RW | PG_U;
if (physmap[1] != 0)
goto physmap_done;
/*
* If we failed above, try memory map with INT 15:E801
*/
vmf.vmf_ax = 0xE801;
if (vm86_intcall(0x15, &vmf) == 0) {
extmem = vmf.vmf_cx + vmf.vmf_dx * 64;
} else {
#if 0
vmf.vmf_ah = 0x88;
vm86_intcall(0x15, &vmf);
extmem = vmf.vmf_ax;
#else
/*
* Prefer the RTC value for extended memory.
*/
extmem = rtcin(RTC_EXTLO) + (rtcin(RTC_EXTHI) << 8);
#endif
}
/*
* Special hack for chipsets that still remap the 384k hole when
* there's 16MB of memory - this really confuses people that
* are trying to use bus mastering ISA controllers with the
* "16MB limit"; they only have 16MB, but the remapping puts
* them beyond the limit.
*
* If extended memory is between 15-16MB (16-17MB phys address range),
* chop it to 15MB.
*/
if ((extmem > 15 * 1024) && (extmem < 16 * 1024))
extmem = 15 * 1024;
#endif /* PC98 */
physmap[0] = 0;
physmap[1] = basemem * 1024;
physmap_idx = 2;
physmap[physmap_idx] = 0x100000;
physmap[physmap_idx + 1] = physmap[physmap_idx] + extmem * 1024;
#ifdef PC98
if ((under16 != 16 * 1024) && (extmem > 15 * 1024)) {
/* 15M - 16M region is cut off, so need to divide chunk */
physmap[physmap_idx + 1] = under16 * 1024;
physmap_idx += 2;
physmap[physmap_idx] = 0x1000000;
physmap[physmap_idx + 1] = physmap[2] + extmem * 1024;
}
#else
physmap_done:
#endif
/*
* Now, physmap contains a map of physical memory.
*/
#ifdef SMP
/* make hole for AP bootstrap code */
physmap[1] = mp_bootaddress(physmap[1] / 1024);
/* look for the MP hardware - needed for apic addresses */
i386_mp_probe();
#endif
/*
* Maxmem isn't the "maximum memory", it's one larger than the
* highest page of the physical address space. It should be
* called something like "Maxphyspage". We may adjust this
* based on ``hw.physmem'' and the results of the memory test.
*/
Maxmem = atop(physmap[physmap_idx + 1]);
#ifdef MAXMEM
Maxmem = MAXMEM / 4;
#endif
/*
* hw.physmem is a size in bytes; we also allow k, m, and g suffixes
* for the appropriate modifiers. This overrides MAXMEM.
*/
if ((cp = getenv("hw.physmem")) != NULL) {
u_int64_t AllowMem, sanity;
char *ep;
sanity = AllowMem = strtouq(cp, &ep, 0);
if ((ep != cp) && (*ep != 0)) {
switch(*ep) {
case 'g':
case 'G':
AllowMem <<= 10;
case 'm':
case 'M':
AllowMem <<= 10;
case 'k':
case 'K':
AllowMem <<= 10;
break;
default:
AllowMem = sanity = 0;
}
if (AllowMem < sanity)
AllowMem = 0;
}
if (AllowMem == 0)
printf("Ignoring invalid memory size of '%s'\n", cp);
else
Maxmem = atop(AllowMem);
freeenv(cp);
}
if (atop(physmap[physmap_idx + 1]) != Maxmem &&
(boothowto & RB_VERBOSE))
printf("Physical memory use set to %ldK\n", Maxmem * 4);
/*
* If Maxmem has been increased beyond what the system has detected,
* extend the last memory segment to the new limit.
*/
if (atop(physmap[physmap_idx + 1]) < Maxmem)
physmap[physmap_idx + 1] = ptoa(Maxmem);
/* call pmap initialization to make new kernel address space */
pmap_bootstrap(first, 0);
/*
* Size up each available chunk of physical memory.
*/
physmap[0] = PAGE_SIZE; /* mask off page 0 */
pa_indx = 0;
phys_avail[pa_indx++] = physmap[0];
phys_avail[pa_indx] = physmap[0];
pte = CMAP1;
/*
* physmap is in bytes, so when converting to page boundaries,
* round up the start address and round down the end address.
*/
for (i = 0; i <= physmap_idx; i += 2) {
vm_offset_t end;
end = ptoa(Maxmem);
if (physmap[i + 1] < end)
end = trunc_page(physmap[i + 1]);
for (pa = round_page(physmap[i]); pa < end; pa += PAGE_SIZE) {
int tmp, page_bad;
int *ptr = (int *)CADDR1;
/*
* block out kernel memory as not available.
*/
if (pa >= 0x100000 && pa < first)
continue;
page_bad = FALSE;
/*
* map page into kernel: valid, read/write,non-cacheable
*/
#ifdef PC98
*pte = pa | PG_V | PG_RW | pg_n;
#else
*pte = pa | PG_V | PG_RW | PG_N;
#endif
invltlb();
tmp = *(int *)ptr;
/*
* Test for alternating 1's and 0's
*/
*(volatile int *)ptr = 0xaaaaaaaa;
if (*(volatile int *)ptr != 0xaaaaaaaa) {
page_bad = TRUE;
}
/*
* Test for alternating 0's and 1's
*/
*(volatile int *)ptr = 0x55555555;
if (*(volatile int *)ptr != 0x55555555) {
page_bad = TRUE;
}
/*
* Test for all 1's
*/
*(volatile int *)ptr = 0xffffffff;
if (*(volatile int *)ptr != 0xffffffff) {
page_bad = TRUE;
}
/*
* Test for all 0's
*/
*(volatile int *)ptr = 0x0;
if (*(volatile int *)ptr != 0x0) {
page_bad = TRUE;
}
/*
* Restore original value.
*/
*(int *)ptr = tmp;
/*
* Adjust array of valid/good pages.
*/
if (page_bad == TRUE) {
continue;
}
/*
* If this good page is a continuation of the
* previous set of good pages, then just increase
* the end pointer. Otherwise start a new chunk.
* Note that "end" points one higher than end,
* making the range >= start and < end.
* If we're also doing a speculative memory
* test and we at or past the end, bump up Maxmem
* so that we keep going. The first bad page
* will terminate the loop.
*/
if (phys_avail[pa_indx] == pa) {
phys_avail[pa_indx] += PAGE_SIZE;
} else {
pa_indx++;
if (pa_indx == PHYS_AVAIL_ARRAY_END) {
printf(
"Too many holes in the physical address space, giving up\n");
pa_indx--;
break;
}
phys_avail[pa_indx++] = pa; /* start */
phys_avail[pa_indx] = pa + PAGE_SIZE; /* end */
}
physmem++;
}
}
*pte = 0;
invltlb();
/*
* XXX
* The last chunk must contain at least one page plus the message
* buffer to avoid complicating other code (message buffer address
* calculation, etc.).
*/
while (phys_avail[pa_indx - 1] + PAGE_SIZE +
round_page(MSGBUF_SIZE) >= phys_avail[pa_indx]) {
physmem -= atop(phys_avail[pa_indx] - phys_avail[pa_indx - 1]);
phys_avail[pa_indx--] = 0;
phys_avail[pa_indx--] = 0;
}
Maxmem = atop(phys_avail[pa_indx]);
/* Trim off space for the message buffer. */
phys_avail[pa_indx] -= round_page(MSGBUF_SIZE);
avail_end = phys_avail[pa_indx];
}
void
init386(first)
int first;
{
struct gate_descriptor *gdp;
int gsel_tss, metadata_missing, off, x;
#ifndef SMP
/* table descriptors - used to load tables by microp */
struct region_descriptor r_gdt, r_idt;
#endif
struct pcpu *pc;
proc0.p_uarea = proc0uarea;
thread0.td_kstack = proc0kstack;
thread0.td_pcb = (struct pcb *)
(thread0.td_kstack + KSTACK_PAGES * PAGE_SIZE) - 1;
atdevbase = ISA_HOLE_START + KERNBASE;
/*
* This may be done better later if it gets more high level
* components in it. If so just link td->td_proc here.
*/
proc_linkup(&proc0, &ksegrp0, &kse0, &thread0);
#ifdef PC98
/*
* Initialize DMAC
*/
pc98_init_dmac();
#endif
metadata_missing = 0;
if (bootinfo.bi_modulep) {
preload_metadata = (caddr_t)bootinfo.bi_modulep + KERNBASE;
preload_bootstrap_relocate(KERNBASE);
} else {
metadata_missing = 1;
}
if (envmode == 1)
kern_envp = static_env;
else if (bootinfo.bi_envp)
kern_envp = (caddr_t)bootinfo.bi_envp + KERNBASE;
/* Init basic tunables, hz etc */
init_param1();
/*
* make gdt memory segments, the code segment goes up to end of the
* page with etext in it, the data segment goes to the end of
* the address space
*/
/*
* XXX text protection is temporarily (?) disabled. The limit was
* i386_btop(round_page(etext)) - 1.
*/
gdt_segs[GCODE_SEL].ssd_limit = atop(0 - 1);
gdt_segs[GDATA_SEL].ssd_limit = atop(0 - 1);
#ifdef SMP
pc = &SMP_prvspace[0].pcpu;
gdt_segs[GPRIV_SEL].ssd_limit =
atop(sizeof(struct privatespace) - 1);
#else
pc = &__pcpu;
gdt_segs[GPRIV_SEL].ssd_limit =
atop(sizeof(struct pcpu) - 1);
#endif
gdt_segs[GPRIV_SEL].ssd_base = (int) pc;
gdt_segs[GPROC0_SEL].ssd_base = (int) &pc->pc_common_tss;
for (x = 0; x < NGDT; x++)
ssdtosd(&gdt_segs[x], &gdt[x].sd);
r_gdt.rd_limit = NGDT * sizeof(gdt[0]) - 1;
r_gdt.rd_base = (int) gdt;
lgdt(&r_gdt);
pcpu_init(pc, 0, sizeof(struct pcpu));
PCPU_SET(prvspace, pc);
PCPU_SET(curthread, &thread0);
/*
* Initialize mutexes.
*
* icu_lock: in order to allow an interrupt to occur in a critical
* section, to set pcpu->ipending (etc...) properly, we
* must be able to get the icu lock, so it can't be
* under witness.
*/
mutex_init();
mtx_init(&clock_lock, "clk", NULL, MTX_SPIN | MTX_RECURSE);
mtx_init(&icu_lock, "icu", NULL, MTX_SPIN | MTX_NOWITNESS);
/* make ldt memory segments */
/*
* XXX - VM_MAXUSER_ADDRESS is an end address, not a max. And it
* should be spelled ...MAX_USER...
*/
ldt_segs[LUCODE_SEL].ssd_limit = atop(VM_MAXUSER_ADDRESS - 1);
ldt_segs[LUDATA_SEL].ssd_limit = atop(VM_MAXUSER_ADDRESS - 1);
for (x = 0; x < sizeof ldt_segs / sizeof ldt_segs[0]; x++)
ssdtosd(&ldt_segs[x], &ldt[x].sd);
_default_ldt = GSEL(GLDT_SEL, SEL_KPL);
lldt(_default_ldt);
PCPU_SET(currentldt, _default_ldt);
/* exceptions */
for (x = 0; x < NIDT; x++)
setidt(x, &IDTVEC(rsvd), SDT_SYS386TGT, SEL_KPL,
GSEL(GCODE_SEL, SEL_KPL));
setidt(0, &IDTVEC(div), SDT_SYS386TGT, SEL_KPL,
GSEL(GCODE_SEL, SEL_KPL));
setidt(1, &IDTVEC(dbg), SDT_SYS386IGT, SEL_KPL,
GSEL(GCODE_SEL, SEL_KPL));
setidt(2, &IDTVEC(nmi), SDT_SYS386TGT, SEL_KPL,
GSEL(GCODE_SEL, SEL_KPL));
setidt(3, &IDTVEC(bpt), SDT_SYS386IGT, SEL_UPL,
GSEL(GCODE_SEL, SEL_KPL));
setidt(4, &IDTVEC(ofl), SDT_SYS386TGT, SEL_UPL,
GSEL(GCODE_SEL, SEL_KPL));
setidt(5, &IDTVEC(bnd), SDT_SYS386TGT, SEL_KPL,
GSEL(GCODE_SEL, SEL_KPL));
setidt(6, &IDTVEC(ill), SDT_SYS386TGT, SEL_KPL,
GSEL(GCODE_SEL, SEL_KPL));
setidt(7, &IDTVEC(dna), SDT_SYS386TGT, SEL_KPL
, GSEL(GCODE_SEL, SEL_KPL));
setidt(8, 0, SDT_SYSTASKGT, SEL_KPL, GSEL(GPANIC_SEL, SEL_KPL));
setidt(9, &IDTVEC(fpusegm), SDT_SYS386TGT, SEL_KPL,
GSEL(GCODE_SEL, SEL_KPL));
setidt(10, &IDTVEC(tss), SDT_SYS386TGT, SEL_KPL,
GSEL(GCODE_SEL, SEL_KPL));
setidt(11, &IDTVEC(missing), SDT_SYS386TGT, SEL_KPL,
GSEL(GCODE_SEL, SEL_KPL));
setidt(12, &IDTVEC(stk), SDT_SYS386TGT, SEL_KPL,
GSEL(GCODE_SEL, SEL_KPL));
setidt(13, &IDTVEC(prot), SDT_SYS386TGT, SEL_KPL,
GSEL(GCODE_SEL, SEL_KPL));
setidt(14, &IDTVEC(page), SDT_SYS386IGT, SEL_KPL,
GSEL(GCODE_SEL, SEL_KPL));
setidt(15, &IDTVEC(rsvd), SDT_SYS386TGT, SEL_KPL,
GSEL(GCODE_SEL, SEL_KPL));
setidt(16, &IDTVEC(fpu), SDT_SYS386TGT, SEL_KPL,
GSEL(GCODE_SEL, SEL_KPL));
setidt(17, &IDTVEC(align), SDT_SYS386TGT, SEL_KPL,
GSEL(GCODE_SEL, SEL_KPL));
setidt(18, &IDTVEC(mchk), SDT_SYS386TGT, SEL_KPL,
GSEL(GCODE_SEL, SEL_KPL));
setidt(19, &IDTVEC(xmm), SDT_SYS386TGT, SEL_KPL,
GSEL(GCODE_SEL, SEL_KPL));
setidt(0x80, &IDTVEC(int0x80_syscall), SDT_SYS386TGT, SEL_UPL,
GSEL(GCODE_SEL, SEL_KPL));
r_idt.rd_limit = sizeof(idt0) - 1;
r_idt.rd_base = (int) idt;
lidt(&r_idt);
/*
* Initialize the console before we print anything out.
*/
cninit();
if (metadata_missing)
printf("WARNING: loader(8) metadata is missing!\n");
#ifdef DEV_ISA
isa_defaultirq();
#endif
#ifdef DDB
kdb_init();
if (boothowto & RB_KDB)
Debugger("Boot flags requested debugger");
#endif
finishidentcpu(); /* Final stage of CPU initialization */
setidt(6, &IDTVEC(ill), SDT_SYS386TGT, SEL_KPL,
GSEL(GCODE_SEL, SEL_KPL));
setidt(13, &IDTVEC(prot), SDT_SYS386TGT, SEL_KPL,
GSEL(GCODE_SEL, SEL_KPL));
initializecpu(); /* Initialize CPU registers */
/* make an initial tss so cpu can get interrupt stack on syscall! */
/* Note: -16 is so we can grow the trapframe if we came from vm86 */
PCPU_SET(common_tss.tss_esp0, thread0.td_kstack +
KSTACK_PAGES * PAGE_SIZE - sizeof(struct pcb) - 16);
PCPU_SET(common_tss.tss_ss0, GSEL(GDATA_SEL, SEL_KPL));
gsel_tss = GSEL(GPROC0_SEL, SEL_KPL);
private_tss = 0;
PCPU_SET(tss_gdt, &gdt[GPROC0_SEL].sd);
PCPU_SET(common_tssd, *PCPU_GET(tss_gdt));
PCPU_SET(common_tss.tss_ioopt, (sizeof (struct i386tss)) << 16);
ltr(gsel_tss);
dblfault_tss.tss_esp = dblfault_tss.tss_esp0 = dblfault_tss.tss_esp1 =
dblfault_tss.tss_esp2 = (int)&dblfault_stack[sizeof(dblfault_stack)];
dblfault_tss.tss_ss = dblfault_tss.tss_ss0 = dblfault_tss.tss_ss1 =
dblfault_tss.tss_ss2 = GSEL(GDATA_SEL, SEL_KPL);
dblfault_tss.tss_cr3 = (int)IdlePTD;
dblfault_tss.tss_eip = (int)dblfault_handler;
dblfault_tss.tss_eflags = PSL_KERNEL;
dblfault_tss.tss_ds = dblfault_tss.tss_es =
dblfault_tss.tss_gs = GSEL(GDATA_SEL, SEL_KPL);
dblfault_tss.tss_fs = GSEL(GPRIV_SEL, SEL_KPL);
dblfault_tss.tss_cs = GSEL(GCODE_SEL, SEL_KPL);
dblfault_tss.tss_ldt = GSEL(GLDT_SEL, SEL_KPL);
vm86_initialize();
getmemsize(first);
init_param2(physmem);
/* now running on new page tables, configured,and u/iom is accessible */
/* Map the message buffer. */
for (off = 0; off < round_page(MSGBUF_SIZE); off += PAGE_SIZE)
pmap_kenter((vm_offset_t)msgbufp + off, avail_end + off);
msgbufinit(msgbufp, MSGBUF_SIZE);
/* make a call gate to reenter kernel with */
gdp = &ldt[LSYS5CALLS_SEL].gd;
x = (int) &IDTVEC(lcall_syscall);
gdp->gd_looffset = x;
gdp->gd_selector = GSEL(GCODE_SEL,SEL_KPL);
gdp->gd_stkcpy = 1;
gdp->gd_type = SDT_SYS386CGT;
gdp->gd_dpl = SEL_UPL;
gdp->gd_p = 1;
gdp->gd_hioffset = x >> 16;
/* XXX does this work? */
ldt[LBSDICALLS_SEL] = ldt[LSYS5CALLS_SEL];
ldt[LSOL26CALLS_SEL] = ldt[LSYS5CALLS_SEL];
/* transfer to user mode */
_ucodesel = LSEL(LUCODE_SEL, SEL_UPL);
_udatasel = LSEL(LUDATA_SEL, SEL_UPL);
/* setup proc 0's pcb */
thread0.td_pcb->pcb_flags = 0; /* XXXKSE */
thread0.td_pcb->pcb_cr3 = (int)IdlePTD;
thread0.td_pcb->pcb_ext = 0;
thread0.td_frame = &proc0_tf;
}
void
cpu_pcpu_init(struct pcpu *pcpu, int cpuid, size_t size)
{
}
#if defined(I586_CPU) && !defined(NO_F00F_HACK)
static void f00f_hack(void *unused);
SYSINIT(f00f_hack, SI_SUB_INTRINSIC, SI_ORDER_FIRST, f00f_hack, NULL);
static void
f00f_hack(void *unused) {
struct gate_descriptor *new_idt;
#ifndef SMP
struct region_descriptor r_idt;
#endif
vm_offset_t tmp;
if (!has_f00f_bug)
return;
GIANT_REQUIRED;
printf("Intel Pentium detected, installing workaround for F00F bug\n");
r_idt.rd_limit = sizeof(idt0) - 1;
tmp = kmem_alloc(kernel_map, PAGE_SIZE * 2);
if (tmp == 0)
panic("kmem_alloc returned 0");
if (((unsigned int)tmp & (PAGE_SIZE-1)) != 0)
panic("kmem_alloc returned non-page-aligned memory");
/* Put the first seven entries in the lower page */
new_idt = (struct gate_descriptor*)(tmp + PAGE_SIZE - (7*8));
bcopy(idt, new_idt, sizeof(idt0));
r_idt.rd_base = (int)new_idt;
lidt(&r_idt);
idt = new_idt;
if (vm_map_protect(kernel_map, tmp, tmp + PAGE_SIZE,
VM_PROT_READ, FALSE) != KERN_SUCCESS)
panic("vm_map_protect failed");
return;
}
#endif /* defined(I586_CPU) && !NO_F00F_HACK */
int
ptrace_set_pc(struct thread *td, unsigned long addr)
{
td->td_frame->tf_eip = addr;
return (0);
}
int
ptrace_single_step(struct thread *td)
{
td->td_frame->tf_eflags |= PSL_T;
return (0);
}
int
fill_regs(struct thread *td, struct reg *regs)
{
struct pcb *pcb;
struct trapframe *tp;
tp = td->td_frame;
regs->r_fs = tp->tf_fs;
regs->r_es = tp->tf_es;
regs->r_ds = tp->tf_ds;
regs->r_edi = tp->tf_edi;
regs->r_esi = tp->tf_esi;
regs->r_ebp = tp->tf_ebp;
regs->r_ebx = tp->tf_ebx;
regs->r_edx = tp->tf_edx;
regs->r_ecx = tp->tf_ecx;
regs->r_eax = tp->tf_eax;
regs->r_eip = tp->tf_eip;
regs->r_cs = tp->tf_cs;
regs->r_eflags = tp->tf_eflags;
regs->r_esp = tp->tf_esp;
regs->r_ss = tp->tf_ss;
pcb = td->td_pcb;
regs->r_gs = pcb->pcb_gs;
return (0);
}
int
set_regs(struct thread *td, struct reg *regs)
{
struct pcb *pcb;
struct trapframe *tp;
tp = td->td_frame;
if (!EFL_SECURE(regs->r_eflags, tp->tf_eflags) ||
!CS_SECURE(regs->r_cs))
return (EINVAL);
tp->tf_fs = regs->r_fs;
tp->tf_es = regs->r_es;
tp->tf_ds = regs->r_ds;
tp->tf_edi = regs->r_edi;
tp->tf_esi = regs->r_esi;
tp->tf_ebp = regs->r_ebp;
tp->tf_ebx = regs->r_ebx;
tp->tf_edx = regs->r_edx;
tp->tf_ecx = regs->r_ecx;
tp->tf_eax = regs->r_eax;
tp->tf_eip = regs->r_eip;
tp->tf_cs = regs->r_cs;
tp->tf_eflags = regs->r_eflags;
tp->tf_esp = regs->r_esp;
tp->tf_ss = regs->r_ss;
pcb = td->td_pcb;
pcb->pcb_gs = regs->r_gs;
return (0);
}
#ifdef CPU_ENABLE_SSE
static void
fill_fpregs_xmm(sv_xmm, sv_87)
struct savexmm *sv_xmm;
struct save87 *sv_87;
{
register struct env87 *penv_87 = &sv_87->sv_env;
register struct envxmm *penv_xmm = &sv_xmm->sv_env;
int i;
bzero(sv_87, sizeof(*sv_87));
/* FPU control/status */
penv_87->en_cw = penv_xmm->en_cw;
penv_87->en_sw = penv_xmm->en_sw;
penv_87->en_tw = penv_xmm->en_tw;
penv_87->en_fip = penv_xmm->en_fip;
penv_87->en_fcs = penv_xmm->en_fcs;
penv_87->en_opcode = penv_xmm->en_opcode;
penv_87->en_foo = penv_xmm->en_foo;
penv_87->en_fos = penv_xmm->en_fos;
/* FPU registers */
for (i = 0; i < 8; ++i)
sv_87->sv_ac[i] = sv_xmm->sv_fp[i].fp_acc;
}
static void
set_fpregs_xmm(sv_87, sv_xmm)
struct save87 *sv_87;
struct savexmm *sv_xmm;
{
register struct env87 *penv_87 = &sv_87->sv_env;
register struct envxmm *penv_xmm = &sv_xmm->sv_env;
int i;
/* FPU control/status */
penv_xmm->en_cw = penv_87->en_cw;
penv_xmm->en_sw = penv_87->en_sw;
penv_xmm->en_tw = penv_87->en_tw;
penv_xmm->en_fip = penv_87->en_fip;
penv_xmm->en_fcs = penv_87->en_fcs;
penv_xmm->en_opcode = penv_87->en_opcode;
penv_xmm->en_foo = penv_87->en_foo;
penv_xmm->en_fos = penv_87->en_fos;
/* FPU registers */
for (i = 0; i < 8; ++i)
sv_xmm->sv_fp[i].fp_acc = sv_87->sv_ac[i];
}
#endif /* CPU_ENABLE_SSE */
int
fill_fpregs(struct thread *td, struct fpreg *fpregs)
{
#ifdef CPU_ENABLE_SSE
if (cpu_fxsr) {
fill_fpregs_xmm(&td->td_pcb->pcb_save.sv_xmm,
(struct save87 *)fpregs);
return (0);
}
#endif /* CPU_ENABLE_SSE */
bcopy(&td->td_pcb->pcb_save.sv_87, fpregs, sizeof *fpregs);
return (0);
}
int
set_fpregs(struct thread *td, struct fpreg *fpregs)
{
#ifdef CPU_ENABLE_SSE
if (cpu_fxsr) {
set_fpregs_xmm((struct save87 *)fpregs,
&td->td_pcb->pcb_save.sv_xmm);
return (0);
}
#endif /* CPU_ENABLE_SSE */
bcopy(fpregs, &td->td_pcb->pcb_save.sv_87, sizeof *fpregs);
return (0);
}
/*
* Get machine context.
*/
int
get_mcontext(struct thread *td, mcontext_t *mcp)
{
struct trapframe *tp;
tp = td->td_frame;
mcp->mc_onstack = sigonstack(tp->tf_esp);
mcp->mc_gs = td->td_pcb->pcb_gs;
mcp->mc_fs = tp->tf_fs;
mcp->mc_es = tp->tf_es;
mcp->mc_ds = tp->tf_ds;
mcp->mc_edi = tp->tf_edi;
mcp->mc_esi = tp->tf_esi;
mcp->mc_ebp = tp->tf_ebp;
mcp->mc_isp = tp->tf_isp;
mcp->mc_ebx = tp->tf_ebx;
mcp->mc_edx = tp->tf_edx;
mcp->mc_ecx = tp->tf_ecx;
mcp->mc_eax = tp->tf_eax;
mcp->mc_eip = tp->tf_eip;
mcp->mc_cs = tp->tf_cs;
mcp->mc_eflags = tp->tf_eflags;
mcp->mc_esp = tp->tf_esp;
mcp->mc_ss = tp->tf_ss;
mcp->mc_len = sizeof(*mcp);
get_fpcontext(td, mcp);
return (0);
}
/*
* Set machine context.
*
* However, we don't set any but the user modifiable flags, and we won't
* touch the cs selector.
*/
int
set_mcontext(struct thread *td, const mcontext_t *mcp)
{
struct trapframe *tp;
int eflags, ret;
tp = td->td_frame;
if (mcp->mc_len != sizeof(*mcp))
return (EINVAL);
eflags = (mcp->mc_eflags & PSL_USERCHANGE) |
(tp->tf_eflags & ~PSL_USERCHANGE);
if ((ret = set_fpcontext(td, mcp)) == 0) {
tp->tf_fs = mcp->mc_fs;
tp->tf_es = mcp->mc_es;
tp->tf_ds = mcp->mc_ds;
tp->tf_edi = mcp->mc_edi;
tp->tf_esi = mcp->mc_esi;
tp->tf_ebp = mcp->mc_ebp;
tp->tf_ebx = mcp->mc_ebx;
tp->tf_edx = mcp->mc_edx;
tp->tf_ecx = mcp->mc_ecx;
tp->tf_eax = mcp->mc_eax;
tp->tf_eip = mcp->mc_eip;
tp->tf_eflags = eflags;
tp->tf_esp = mcp->mc_esp;
tp->tf_ss = mcp->mc_ss;
td->td_pcb->pcb_gs = mcp->mc_gs;
ret = 0;
}
return (ret);
}
static void
get_fpcontext(struct thread *td, mcontext_t *mcp)
{
#ifndef DEV_NPX
mcp->mc_fpformat = _MC_FPFMT_NODEV;
mcp->mc_ownedfp = _MC_FPOWNED_NONE;
#else
union savefpu *addr;
/*
* XXX mc_fpstate might be misaligned, since its declaration is not
* unportabilized using __attribute__((aligned(16))) like the
* declaration of struct savemm, and anyway, alignment doesn't work
* for auto variables since we don't use gcc's pessimal stack
* alignment. Work around this by abusing the spare fields after
* mcp->mc_fpstate.
*
* XXX unpessimize most cases by only aligning when fxsave might be
* called, although this requires knowing too much about
* npxgetregs()'s internals.
*/
addr = (union savefpu *)&mcp->mc_fpstate;
if (td == PCPU_GET(fpcurthread) &&
#ifdef CPU_ENABLE_SSE
cpu_fxsr &&
#endif
((uintptr_t)(void *)addr & 0xF)) {
do
addr = (void *)((char *)addr + 4);
while ((uintptr_t)(void *)addr & 0xF);
}
mcp->mc_ownedfp = npxgetregs(td, addr);
if (addr != (union savefpu *)&mcp->mc_fpstate) {
bcopy(addr, &mcp->mc_fpstate, sizeof(mcp->mc_fpstate));
bzero(&mcp->mc_spare2, sizeof(mcp->mc_spare2));
}
mcp->mc_fpformat = npxformat();
#endif
}
static int
set_fpcontext(struct thread *td, const mcontext_t *mcp)
{
union savefpu *addr;
if (mcp->mc_fpformat == _MC_FPFMT_NODEV)
return (0);
else if (mcp->mc_fpformat != _MC_FPFMT_387 &&
mcp->mc_fpformat != _MC_FPFMT_XMM)
return (EINVAL);
else if (mcp->mc_ownedfp == _MC_FPOWNED_NONE)
/* We don't care what state is left in the FPU or PCB. */
fpstate_drop(td);
else if (mcp->mc_ownedfp == _MC_FPOWNED_FPU ||
mcp->mc_ownedfp == _MC_FPOWNED_PCB) {
/* XXX align as above. */
addr = (union savefpu *)&mcp->mc_fpstate;
if (td == PCPU_GET(fpcurthread) &&
#ifdef CPU_ENABLE_SSE
cpu_fxsr &&
#endif
((uintptr_t)(void *)addr & 0xF)) {
do
addr = (void *)((char *)addr + 4);
while ((uintptr_t)(void *)addr & 0xF);
bcopy(&mcp->mc_fpstate, addr, sizeof(mcp->mc_fpstate));
}
#ifdef DEV_NPX
/*
* XXX we violate the dubious requirement that npxsetregs()
* be called with interrupts disabled.
*/
npxsetregs(td, addr);
#endif
/*
* Don't bother putting things back where they were in the
* misaligned case, since we know that the caller won't use
* them again.
*/
} else
return (EINVAL);
return (0);
}
static void
fpstate_drop(struct thread *td)
{
register_t s;
s = intr_disable();
#ifdef DEV_NPX
if (PCPU_GET(fpcurthread) == td)
npxdrop();
#endif
/*
* XXX force a full drop of the npx. The above only drops it if we
* owned it. npxgetregs() has the same bug in the !cpu_fxsr case.
*
* XXX I don't much like npxgetregs()'s semantics of doing a full
* drop. Dropping only to the pcb matches fnsave's behaviour.
* We only need to drop to !PCB_INITDONE in sendsig(). But
* sendsig() is the only caller of npxgetregs()... perhaps we just
* have too many layers.
*/
curthread->td_pcb->pcb_flags &= ~PCB_NPXINITDONE;
intr_restore(s);
}
int
fill_dbregs(struct thread *td, struct dbreg *dbregs)
{
struct pcb *pcb;
if (td == NULL) {
dbregs->dr[0] = rdr0();
dbregs->dr[1] = rdr1();
dbregs->dr[2] = rdr2();
dbregs->dr[3] = rdr3();
dbregs->dr[4] = rdr4();
dbregs->dr[5] = rdr5();
dbregs->dr[6] = rdr6();
dbregs->dr[7] = rdr7();
} else {
pcb = td->td_pcb;
dbregs->dr[0] = pcb->pcb_dr0;
dbregs->dr[1] = pcb->pcb_dr1;
dbregs->dr[2] = pcb->pcb_dr2;
dbregs->dr[3] = pcb->pcb_dr3;
dbregs->dr[4] = 0;
dbregs->dr[5] = 0;
dbregs->dr[6] = pcb->pcb_dr6;
dbregs->dr[7] = pcb->pcb_dr7;
}
return (0);
}
int
set_dbregs(struct thread *td, struct dbreg *dbregs)
{
struct pcb *pcb;
int i;
u_int32_t mask1, mask2;
if (td == NULL) {
load_dr0(dbregs->dr[0]);
load_dr1(dbregs->dr[1]);
load_dr2(dbregs->dr[2]);
load_dr3(dbregs->dr[3]);
load_dr4(dbregs->dr[4]);
load_dr5(dbregs->dr[5]);
load_dr6(dbregs->dr[6]);
load_dr7(dbregs->dr[7]);
} else {
/*
* Don't let an illegal value for dr7 get set. Specifically,
* check for undefined settings. Setting these bit patterns
* result in undefined behaviour and can lead to an unexpected
* TRCTRAP.
*/
for (i = 0, mask1 = 0x3<<16, mask2 = 0x2<<16; i < 8;
i++, mask1 <<= 2, mask2 <<= 2)
if ((dbregs->dr[7] & mask1) == mask2)
return (EINVAL);
pcb = td->td_pcb;
/*
* Don't let a process set a breakpoint that is not within the
* process's address space. If a process could do this, it
* could halt the system by setting a breakpoint in the kernel
* (if ddb was enabled). Thus, we need to check to make sure
* that no breakpoints are being enabled for addresses outside
* process's address space, unless, perhaps, we were called by
* uid 0.
*
* XXX - what about when the watched area of the user's
* address space is written into from within the kernel
* ... wouldn't that still cause a breakpoint to be generated
* from within kernel mode?
*/
if (suser(td) != 0) {
if (dbregs->dr[7] & 0x3) {
/* dr0 is enabled */
if (dbregs->dr[0] >= VM_MAXUSER_ADDRESS)
return (EINVAL);
}
if (dbregs->dr[7] & (0x3<<2)) {
/* dr1 is enabled */
if (dbregs->dr[1] >= VM_MAXUSER_ADDRESS)
return (EINVAL);
}
if (dbregs->dr[7] & (0x3<<4)) {
/* dr2 is enabled */
if (dbregs->dr[2] >= VM_MAXUSER_ADDRESS)
return (EINVAL);
}
if (dbregs->dr[7] & (0x3<<6)) {
/* dr3 is enabled */
if (dbregs->dr[3] >= VM_MAXUSER_ADDRESS)
return (EINVAL);
}
}
pcb->pcb_dr0 = dbregs->dr[0];
pcb->pcb_dr1 = dbregs->dr[1];
pcb->pcb_dr2 = dbregs->dr[2];
pcb->pcb_dr3 = dbregs->dr[3];
pcb->pcb_dr6 = dbregs->dr[6];
pcb->pcb_dr7 = dbregs->dr[7];
pcb->pcb_flags |= PCB_DBREGS;
}
return (0);
}
/*
* Return > 0 if a hardware breakpoint has been hit, and the
* breakpoint was in user space. Return 0, otherwise.
*/
int
user_dbreg_trap(void)
{
u_int32_t dr7, dr6; /* debug registers dr6 and dr7 */
u_int32_t bp; /* breakpoint bits extracted from dr6 */
int nbp; /* number of breakpoints that triggered */
caddr_t addr[4]; /* breakpoint addresses */
int i;
dr7 = rdr7();
if ((dr7 & 0x000000ff) == 0) {
/*
* all GE and LE bits in the dr7 register are zero,
* thus the trap couldn't have been caused by the
* hardware debug registers
*/
return 0;
}
nbp = 0;
dr6 = rdr6();
bp = dr6 & 0x0000000f;
if (!bp) {
/*
* None of the breakpoint bits are set meaning this
* trap was not caused by any of the debug registers
*/
return 0;
}
/*
* at least one of the breakpoints were hit, check to see
* which ones and if any of them are user space addresses
*/
if (bp & 0x01) {
addr[nbp++] = (caddr_t)rdr0();
}
if (bp & 0x02) {
addr[nbp++] = (caddr_t)rdr1();
}
if (bp & 0x04) {
addr[nbp++] = (caddr_t)rdr2();
}
if (bp & 0x08) {
addr[nbp++] = (caddr_t)rdr3();
}
for (i=0; i<nbp; i++) {
if (addr[i] <
(caddr_t)VM_MAXUSER_ADDRESS) {
/*
* addr[i] is in user space
*/
return nbp;
}
}
/*
* None of the breakpoints are in user space.
*/
return 0;
}
#ifndef DDB
void
Debugger(const char *msg)
{
printf("Debugger(\"%s\") called.\n", msg);
}
#endif /* no DDB */
#ifdef DDB
/*
* Provide inb() and outb() as functions. They are normally only
* available as macros calling inlined functions, thus cannot be
* called inside DDB.
*
* The actual code is stolen from <machine/cpufunc.h>, and de-inlined.
*/
#undef inb
#undef outb
/* silence compiler warnings */
u_char inb(u_int);
void outb(u_int, u_char);
u_char
inb(u_int port)
{
u_char data;
/*
* We use %%dx and not %1 here because i/o is done at %dx and not at
* %edx, while gcc generates inferior code (movw instead of movl)
* if we tell it to load (u_short) port.
*/
__asm __volatile("inb %%dx,%0" : "=a" (data) : "d" (port));
return (data);
}
void
outb(u_int port, u_char data)
{
u_char al;
/*
* Use an unnecessary assignment to help gcc's register allocator.
* This make a large difference for gcc-1.40 and a tiny difference
* for gcc-2.6.0. For gcc-1.40, al had to be ``asm("ax")'' for
* best results. gcc-2.6.0 can't handle this.
*/
al = data;
__asm __volatile("outb %0,%%dx" : : "a" (al), "d" (port));
}
#endif /* DDB */
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