The Design and Implementation of the FreeBSD Operating System, Second Edition
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FreeBSD/Linux Kernel Cross Reference
sys/pc98/pc98/machdep.c

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    1 /*-
    2  * Copyright (c) 1992 Terrence R. Lambert.
    3  * Copyright (c) 1982, 1987, 1990 The Regents of the University of California.
    4  * All rights reserved.
    5  *
    6  * This code is derived from software contributed to Berkeley by
    7  * William Jolitz.
    8  *
    9  * Redistribution and use in source and binary forms, with or without
   10  * modification, are permitted provided that the following conditions
   11  * are met:
   12  * 1. Redistributions of source code must retain the above copyright
   13  *    notice, this list of conditions and the following disclaimer.
   14  * 2. Redistributions in binary form must reproduce the above copyright
   15  *    notice, this list of conditions and the following disclaimer in the
   16  *    documentation and/or other materials provided with the distribution.
   17  * 3. All advertising materials mentioning features or use of this software
   18  *    must display the following acknowledgement:
   19  *      This product includes software developed by the University of
   20  *      California, Berkeley and its contributors.
   21  * 4. Neither the name of the University nor the names of its contributors
   22  *    may be used to endorse or promote products derived from this software
   23  *    without specific prior written permission.
   24  *
   25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   35  * SUCH DAMAGE.
   36  *
   37  *      from: @(#)machdep.c     7.4 (Berkeley) 6/3/91
   38  */
   39 
   40 #include <sys/cdefs.h>
   41 __FBSDID("$FreeBSD$");
   42 
   43 #include "opt_atalk.h"
   44 #include "opt_compat.h"
   45 #include "opt_cpu.h"
   46 #include "opt_ddb.h"
   47 #include "opt_inet.h"
   48 #include "opt_ipx.h"
   49 #include "opt_isa.h"
   50 #include "opt_kstack_pages.h"
   51 #include "opt_maxmem.h"
   52 #include "opt_msgbuf.h"
   53 #include "opt_npx.h"
   54 #include "opt_perfmon.h"
   55 
   56 #include <sys/param.h>
   57 #include <sys/proc.h>
   58 #include <sys/systm.h>
   59 #include <sys/bio.h>
   60 #include <sys/buf.h>
   61 #include <sys/bus.h>
   62 #include <sys/callout.h>
   63 #include <sys/clock.h>
   64 #include <sys/cons.h>
   65 #include <sys/cpu.h>
   66 #include <sys/eventhandler.h>
   67 #include <sys/exec.h>
   68 #include <sys/imgact.h>
   69 #include <sys/kdb.h>
   70 #include <sys/kernel.h>
   71 #include <sys/ktr.h>
   72 #include <sys/linker.h>
   73 #include <sys/lock.h>
   74 #include <sys/malloc.h>
   75 #include <sys/memrange.h>
   76 #include <sys/msgbuf.h>
   77 #include <sys/mutex.h>
   78 #include <sys/pcpu.h>
   79 #include <sys/ptrace.h>
   80 #include <sys/reboot.h>
   81 #include <sys/sched.h>
   82 #include <sys/signalvar.h>
   83 #include <sys/sysctl.h>
   84 #include <sys/sysent.h>
   85 #include <sys/sysproto.h>
   86 #include <sys/ucontext.h>
   87 #include <sys/vmmeter.h>
   88 
   89 #include <vm/vm.h>
   90 #include <vm/vm_extern.h>
   91 #include <vm/vm_kern.h>
   92 #include <vm/vm_page.h>
   93 #include <vm/vm_map.h>
   94 #include <vm/vm_object.h>
   95 #include <vm/vm_pager.h>
   96 #include <vm/vm_param.h>
   97 
   98 #ifdef DDB
   99 #ifndef KDB
  100 #error KDB must be enabled in order for DDB to work!
  101 #endif
  102 #include <ddb/ddb.h>
  103 #include <ddb/db_sym.h>
  104 #endif
  105 
  106 #include <pc98/pc98/pc98_machdep.h>
  107 
  108 #include <net/netisr.h>
  109 
  110 #include <machine/bootinfo.h>
  111 #include <machine/clock.h>
  112 #include <machine/cpu.h>
  113 #include <machine/cputypes.h>
  114 #include <machine/intr_machdep.h>
  115 #include <machine/md_var.h>
  116 #include <machine/pc/bios.h>
  117 #include <machine/pcb.h>
  118 #include <machine/pcb_ext.h>
  119 #include <machine/proc.h>
  120 #include <machine/reg.h>
  121 #include <machine/sigframe.h>
  122 #include <machine/specialreg.h>
  123 #include <machine/vm86.h>
  124 #ifdef PERFMON
  125 #include <machine/perfmon.h>
  126 #endif
  127 #ifdef SMP
  128 #include <machine/smp.h>
  129 #endif
  130 
  131 #ifdef DEV_ISA
  132 #include <i386/isa/icu.h>
  133 #endif
  134 
  135 /* Sanity check for __curthread() */
  136 CTASSERT(offsetof(struct pcpu, pc_curthread) == 0);
  137 
  138 extern void init386(int first);
  139 extern void dblfault_handler(void);
  140 
  141 extern void printcpuinfo(void); /* XXX header file */
  142 extern void finishidentcpu(void);
  143 extern void panicifcpuunsupported(void);
  144 extern void initializecpu(void);
  145 
  146 #define CS_SECURE(cs)           (ISPL(cs) == SEL_UPL)
  147 #define EFL_SECURE(ef, oef)     ((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0)
  148 
  149 #if !defined(CPU_DISABLE_SSE) && defined(I686_CPU)
  150 #define CPU_ENABLE_SSE
  151 #endif
  152 
  153 static void cpu_startup(void *);
  154 static void fpstate_drop(struct thread *td);
  155 static void get_fpcontext(struct thread *td, mcontext_t *mcp);
  156 static int  set_fpcontext(struct thread *td, const mcontext_t *mcp);
  157 #ifdef CPU_ENABLE_SSE
  158 static void set_fpregs_xmm(struct save87 *, struct savexmm *);
  159 static void fill_fpregs_xmm(struct savexmm *, struct save87 *);
  160 #endif /* CPU_ENABLE_SSE */
  161 SYSINIT(cpu, SI_SUB_CPU, SI_ORDER_FIRST, cpu_startup, NULL);
  162 
  163 int     need_pre_dma_flush;     /* If 1, use wbinvd befor DMA transfer. */
  164 int     need_post_dma_flush;    /* If 1, use invd after DMA transfer. */
  165 
  166 #ifdef DDB
  167 extern vm_offset_t ksym_start, ksym_end;
  168 #endif
  169 
  170 int     _udatasel, _ucodesel;
  171 u_int   basemem;
  172 
  173 static int      ispc98 = 1;
  174 SYSCTL_INT(_machdep, OID_AUTO, ispc98, CTLFLAG_RD, &ispc98, 0, "");
  175 
  176 int cold = 1;
  177 
  178 #ifdef COMPAT_43
  179 static void osendsig(sig_t catcher, ksiginfo_t *, sigset_t *mask);
  180 #endif
  181 #ifdef COMPAT_FREEBSD4
  182 static void freebsd4_sendsig(sig_t catcher, ksiginfo_t *, sigset_t *mask);
  183 #endif
  184 
  185 long Maxmem = 0;
  186 long realmem = 0;
  187 
  188 /*
  189  * The number of PHYSMAP entries must be one less than the number of
  190  * PHYSSEG entries because the PHYSMAP entry that spans the largest
  191  * physical address that is accessible by ISA DMA is split into two
  192  * PHYSSEG entries.
  193  */
  194 #define PHYSMAP_SIZE    (2 * (VM_PHYSSEG_MAX - 1))
  195 
  196 vm_paddr_t phys_avail[PHYSMAP_SIZE + 2];
  197 vm_paddr_t dump_avail[PHYSMAP_SIZE + 2];
  198 
  199 /* must be 2 less so 0 0 can signal end of chunks */
  200 #define PHYS_AVAIL_ARRAY_END ((sizeof(phys_avail) / sizeof(phys_avail[0])) - 2)
  201 #define DUMP_AVAIL_ARRAY_END ((sizeof(dump_avail) / sizeof(dump_avail[0])) - 2)
  202 
  203 struct kva_md_info kmi;
  204 
  205 static struct trapframe proc0_tf;
  206 struct pcpu __pcpu[MAXCPU];
  207 
  208 struct mtx icu_lock;
  209 
  210 struct mem_range_softc mem_range_softc;
  211 
  212 static void
  213 cpu_startup(dummy)
  214         void *dummy;
  215 {
  216         /*
  217          * Good {morning,afternoon,evening,night}.
  218          */
  219         startrtclock();
  220         printcpuinfo();
  221         panicifcpuunsupported();
  222 #ifdef PERFMON
  223         perfmon_init();
  224 #endif
  225         printf("real memory  = %ju (%ju MB)\n", ptoa((uintmax_t)Maxmem),
  226             ptoa((uintmax_t)Maxmem) / 1048576);
  227         realmem = Maxmem;
  228         /*
  229          * Display any holes after the first chunk of extended memory.
  230          */
  231         if (bootverbose) {
  232                 int indx;
  233 
  234                 printf("Physical memory chunk(s):\n");
  235                 for (indx = 0; phys_avail[indx + 1] != 0; indx += 2) {
  236                         vm_paddr_t size;
  237 
  238                         size = phys_avail[indx + 1] - phys_avail[indx];
  239                         printf(
  240                             "0x%016jx - 0x%016jx, %ju bytes (%ju pages)\n",
  241                             (uintmax_t)phys_avail[indx],
  242                             (uintmax_t)phys_avail[indx + 1] - 1,
  243                             (uintmax_t)size, (uintmax_t)size / PAGE_SIZE);
  244                 }
  245         }
  246 
  247         vm_ksubmap_init(&kmi);
  248 
  249         printf("avail memory = %ju (%ju MB)\n",
  250             ptoa((uintmax_t)cnt.v_free_count),
  251             ptoa((uintmax_t)cnt.v_free_count) / 1048576);
  252 
  253         /*
  254          * Set up buffers, so they can be used to read disk labels.
  255          */
  256         bufinit();
  257         vm_pager_bufferinit();
  258 
  259         cpu_setregs();
  260 }
  261 
  262 /*
  263  * Send an interrupt to process.
  264  *
  265  * Stack is set up to allow sigcode stored
  266  * at top to call routine, followed by kcall
  267  * to sigreturn routine below.  After sigreturn
  268  * resets the signal mask, the stack, and the
  269  * frame pointer, it returns to the user
  270  * specified pc, psl.
  271  */
  272 #ifdef COMPAT_43
  273 static void
  274 osendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask)
  275 {
  276         struct osigframe sf, *fp;
  277         struct proc *p;
  278         struct thread *td;
  279         struct sigacts *psp;
  280         struct trapframe *regs;
  281         int sig;
  282         int oonstack;
  283 
  284         td = curthread;
  285         p = td->td_proc;
  286         PROC_LOCK_ASSERT(p, MA_OWNED);
  287         sig = ksi->ksi_signo;
  288         psp = p->p_sigacts;
  289         mtx_assert(&psp->ps_mtx, MA_OWNED);
  290         regs = td->td_frame;
  291         oonstack = sigonstack(regs->tf_esp);
  292 
  293         /* Allocate space for the signal handler context. */
  294         if ((td->td_pflags & TDP_ALTSTACK) && !oonstack &&
  295             SIGISMEMBER(psp->ps_sigonstack, sig)) {
  296                 fp = (struct osigframe *)(td->td_sigstk.ss_sp +
  297                     td->td_sigstk.ss_size - sizeof(struct osigframe));
  298 #if defined(COMPAT_43)
  299                 td->td_sigstk.ss_flags |= SS_ONSTACK;
  300 #endif
  301         } else
  302                 fp = (struct osigframe *)regs->tf_esp - 1;
  303 
  304         /* Translate the signal if appropriate. */
  305         if (p->p_sysent->sv_sigtbl && sig <= p->p_sysent->sv_sigsize)
  306                 sig = p->p_sysent->sv_sigtbl[_SIG_IDX(sig)];
  307 
  308         /* Build the argument list for the signal handler. */
  309         sf.sf_signum = sig;
  310         sf.sf_scp = (register_t)&fp->sf_siginfo.si_sc;
  311         if (SIGISMEMBER(psp->ps_siginfo, sig)) {
  312                 /* Signal handler installed with SA_SIGINFO. */
  313                 sf.sf_arg2 = (register_t)&fp->sf_siginfo;
  314                 sf.sf_siginfo.si_signo = sig;
  315                 sf.sf_siginfo.si_code = ksi->ksi_code;
  316                 sf.sf_ahu.sf_action = (__osiginfohandler_t *)catcher;
  317         } else {
  318                 /* Old FreeBSD-style arguments. */
  319                 sf.sf_arg2 = ksi->ksi_code;
  320                 sf.sf_addr = (register_t)ksi->ksi_addr;
  321                 sf.sf_ahu.sf_handler = catcher;
  322         }
  323         mtx_unlock(&psp->ps_mtx);
  324         PROC_UNLOCK(p);
  325 
  326         /* Save most if not all of trap frame. */
  327         sf.sf_siginfo.si_sc.sc_eax = regs->tf_eax;
  328         sf.sf_siginfo.si_sc.sc_ebx = regs->tf_ebx;
  329         sf.sf_siginfo.si_sc.sc_ecx = regs->tf_ecx;
  330         sf.sf_siginfo.si_sc.sc_edx = regs->tf_edx;
  331         sf.sf_siginfo.si_sc.sc_esi = regs->tf_esi;
  332         sf.sf_siginfo.si_sc.sc_edi = regs->tf_edi;
  333         sf.sf_siginfo.si_sc.sc_cs = regs->tf_cs;
  334         sf.sf_siginfo.si_sc.sc_ds = regs->tf_ds;
  335         sf.sf_siginfo.si_sc.sc_ss = regs->tf_ss;
  336         sf.sf_siginfo.si_sc.sc_es = regs->tf_es;
  337         sf.sf_siginfo.si_sc.sc_fs = regs->tf_fs;
  338         sf.sf_siginfo.si_sc.sc_gs = rgs();
  339         sf.sf_siginfo.si_sc.sc_isp = regs->tf_isp;
  340 
  341         /* Build the signal context to be used by osigreturn(). */
  342         sf.sf_siginfo.si_sc.sc_onstack = (oonstack) ? 1 : 0;
  343         SIG2OSIG(*mask, sf.sf_siginfo.si_sc.sc_mask);
  344         sf.sf_siginfo.si_sc.sc_sp = regs->tf_esp;
  345         sf.sf_siginfo.si_sc.sc_fp = regs->tf_ebp;
  346         sf.sf_siginfo.si_sc.sc_pc = regs->tf_eip;
  347         sf.sf_siginfo.si_sc.sc_ps = regs->tf_eflags;
  348         sf.sf_siginfo.si_sc.sc_trapno = regs->tf_trapno;
  349         sf.sf_siginfo.si_sc.sc_err = regs->tf_err;
  350 
  351         /*
  352          * If we're a vm86 process, we want to save the segment registers.
  353          * We also change eflags to be our emulated eflags, not the actual
  354          * eflags.
  355          */
  356         if (regs->tf_eflags & PSL_VM) {
  357                 /* XXX confusing names: `tf' isn't a trapframe; `regs' is. */
  358                 struct trapframe_vm86 *tf = (struct trapframe_vm86 *)regs;
  359                 struct vm86_kernel *vm86 = &td->td_pcb->pcb_ext->ext_vm86;
  360 
  361                 sf.sf_siginfo.si_sc.sc_gs = tf->tf_vm86_gs;
  362                 sf.sf_siginfo.si_sc.sc_fs = tf->tf_vm86_fs;
  363                 sf.sf_siginfo.si_sc.sc_es = tf->tf_vm86_es;
  364                 sf.sf_siginfo.si_sc.sc_ds = tf->tf_vm86_ds;
  365 
  366                 if (vm86->vm86_has_vme == 0)
  367                         sf.sf_siginfo.si_sc.sc_ps =
  368                             (tf->tf_eflags & ~(PSL_VIF | PSL_VIP)) |
  369                             (vm86->vm86_eflags & (PSL_VIF | PSL_VIP));
  370 
  371                 /* See sendsig() for comments. */
  372                 tf->tf_eflags &= ~(PSL_VM | PSL_NT | PSL_VIF | PSL_VIP);
  373         }
  374 
  375         /*
  376          * Copy the sigframe out to the user's stack.
  377          */
  378         if (copyout(&sf, fp, sizeof(*fp)) != 0) {
  379 #ifdef DEBUG
  380                 printf("process %ld has trashed its stack\n", (long)p->p_pid);
  381 #endif
  382                 PROC_LOCK(p);
  383                 sigexit(td, SIGILL);
  384         }
  385 
  386         regs->tf_esp = (int)fp;
  387         regs->tf_eip = PS_STRINGS - szosigcode;
  388         regs->tf_eflags &= ~(PSL_T | PSL_D);
  389         regs->tf_cs = _ucodesel;
  390         regs->tf_ds = _udatasel;
  391         regs->tf_es = _udatasel;
  392         regs->tf_fs = _udatasel;
  393         load_gs(_udatasel);
  394         regs->tf_ss = _udatasel;
  395         PROC_LOCK(p);
  396         mtx_lock(&psp->ps_mtx);
  397 }
  398 #endif /* COMPAT_43 */
  399 
  400 #ifdef COMPAT_FREEBSD4
  401 static void
  402 freebsd4_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask)
  403 {
  404         struct sigframe4 sf, *sfp;
  405         struct proc *p;
  406         struct thread *td;
  407         struct sigacts *psp;
  408         struct trapframe *regs;
  409         int sig;
  410         int oonstack;
  411 
  412         td = curthread;
  413         p = td->td_proc;
  414         PROC_LOCK_ASSERT(p, MA_OWNED);
  415         sig = ksi->ksi_signo;
  416         psp = p->p_sigacts;
  417         mtx_assert(&psp->ps_mtx, MA_OWNED);
  418         regs = td->td_frame;
  419         oonstack = sigonstack(regs->tf_esp);
  420 
  421         /* Save user context. */
  422         bzero(&sf, sizeof(sf));
  423         sf.sf_uc.uc_sigmask = *mask;
  424         sf.sf_uc.uc_stack = td->td_sigstk;
  425         sf.sf_uc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK)
  426             ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
  427         sf.sf_uc.uc_mcontext.mc_onstack = (oonstack) ? 1 : 0;
  428         sf.sf_uc.uc_mcontext.mc_gs = rgs();
  429         bcopy(regs, &sf.sf_uc.uc_mcontext.mc_fs, sizeof(*regs));
  430 
  431         /* Allocate space for the signal handler context. */
  432         if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack &&
  433             SIGISMEMBER(psp->ps_sigonstack, sig)) {
  434                 sfp = (struct sigframe4 *)(td->td_sigstk.ss_sp +
  435                     td->td_sigstk.ss_size - sizeof(struct sigframe4));
  436 #if defined(COMPAT_43)
  437                 td->td_sigstk.ss_flags |= SS_ONSTACK;
  438 #endif
  439         } else
  440                 sfp = (struct sigframe4 *)regs->tf_esp - 1;
  441 
  442         /* Translate the signal if appropriate. */
  443         if (p->p_sysent->sv_sigtbl && sig <= p->p_sysent->sv_sigsize)
  444                 sig = p->p_sysent->sv_sigtbl[_SIG_IDX(sig)];
  445 
  446         /* Build the argument list for the signal handler. */
  447         sf.sf_signum = sig;
  448         sf.sf_ucontext = (register_t)&sfp->sf_uc;
  449         if (SIGISMEMBER(psp->ps_siginfo, sig)) {
  450                 /* Signal handler installed with SA_SIGINFO. */
  451                 sf.sf_siginfo = (register_t)&sfp->sf_si;
  452                 sf.sf_ahu.sf_action = (__siginfohandler_t *)catcher;
  453 
  454                 /* Fill in POSIX parts */
  455                 sf.sf_si.si_signo = sig;
  456                 sf.sf_si.si_code = ksi->ksi_code;
  457                 sf.sf_si.si_addr = ksi->ksi_addr;
  458         } else {
  459                 /* Old FreeBSD-style arguments. */
  460                 sf.sf_siginfo = ksi->ksi_code;
  461                 sf.sf_addr = (register_t)ksi->ksi_addr;
  462                 sf.sf_ahu.sf_handler = catcher;
  463         }
  464         mtx_unlock(&psp->ps_mtx);
  465         PROC_UNLOCK(p);
  466 
  467         /*
  468          * If we're a vm86 process, we want to save the segment registers.
  469          * We also change eflags to be our emulated eflags, not the actual
  470          * eflags.
  471          */
  472         if (regs->tf_eflags & PSL_VM) {
  473                 struct trapframe_vm86 *tf = (struct trapframe_vm86 *)regs;
  474                 struct vm86_kernel *vm86 = &td->td_pcb->pcb_ext->ext_vm86;
  475 
  476                 sf.sf_uc.uc_mcontext.mc_gs = tf->tf_vm86_gs;
  477                 sf.sf_uc.uc_mcontext.mc_fs = tf->tf_vm86_fs;
  478                 sf.sf_uc.uc_mcontext.mc_es = tf->tf_vm86_es;
  479                 sf.sf_uc.uc_mcontext.mc_ds = tf->tf_vm86_ds;
  480 
  481                 if (vm86->vm86_has_vme == 0)
  482                         sf.sf_uc.uc_mcontext.mc_eflags =
  483                             (tf->tf_eflags & ~(PSL_VIF | PSL_VIP)) |
  484                             (vm86->vm86_eflags & (PSL_VIF | PSL_VIP));
  485 
  486                 /*
  487                  * Clear PSL_NT to inhibit T_TSSFLT faults on return from
  488                  * syscalls made by the signal handler.  This just avoids
  489                  * wasting time for our lazy fixup of such faults.  PSL_NT
  490                  * does nothing in vm86 mode, but vm86 programs can set it
  491                  * almost legitimately in probes for old cpu types.
  492                  */
  493                 tf->tf_eflags &= ~(PSL_VM | PSL_NT | PSL_VIF | PSL_VIP);
  494         }
  495 
  496         /*
  497          * Copy the sigframe out to the user's stack.
  498          */
  499         if (copyout(&sf, sfp, sizeof(*sfp)) != 0) {
  500 #ifdef DEBUG
  501                 printf("process %ld has trashed its stack\n", (long)p->p_pid);
  502 #endif
  503                 PROC_LOCK(p);
  504                 sigexit(td, SIGILL);
  505         }
  506 
  507         regs->tf_esp = (int)sfp;
  508         regs->tf_eip = PS_STRINGS - szfreebsd4_sigcode;
  509         regs->tf_eflags &= ~(PSL_T | PSL_D);
  510         regs->tf_cs = _ucodesel;
  511         regs->tf_ds = _udatasel;
  512         regs->tf_es = _udatasel;
  513         regs->tf_fs = _udatasel;
  514         regs->tf_ss = _udatasel;
  515         PROC_LOCK(p);
  516         mtx_lock(&psp->ps_mtx);
  517 }
  518 #endif  /* COMPAT_FREEBSD4 */
  519 
  520 void
  521 sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask)
  522 {
  523         struct sigframe sf, *sfp;
  524         struct proc *p;
  525         struct thread *td;
  526         struct sigacts *psp;
  527         char *sp;
  528         struct trapframe *regs;
  529         int sig;
  530         int oonstack;
  531 
  532         td = curthread;
  533         p = td->td_proc;
  534         PROC_LOCK_ASSERT(p, MA_OWNED);
  535         sig = ksi->ksi_signo;
  536         psp = p->p_sigacts;
  537         mtx_assert(&psp->ps_mtx, MA_OWNED);
  538 #ifdef COMPAT_FREEBSD4
  539         if (SIGISMEMBER(psp->ps_freebsd4, sig)) {
  540                 freebsd4_sendsig(catcher, ksi, mask);
  541                 return;
  542         }
  543 #endif
  544 #ifdef COMPAT_43
  545         if (SIGISMEMBER(psp->ps_osigset, sig)) {
  546                 osendsig(catcher, ksi, mask);
  547                 return;
  548         }
  549 #endif
  550         regs = td->td_frame;
  551         oonstack = sigonstack(regs->tf_esp);
  552 
  553         /* Save user context. */
  554         bzero(&sf, sizeof(sf));
  555         sf.sf_uc.uc_sigmask = *mask;
  556         sf.sf_uc.uc_stack = td->td_sigstk;
  557         sf.sf_uc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK)
  558             ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
  559         sf.sf_uc.uc_mcontext.mc_onstack = (oonstack) ? 1 : 0;
  560         sf.sf_uc.uc_mcontext.mc_gs = rgs();
  561         bcopy(regs, &sf.sf_uc.uc_mcontext.mc_fs, sizeof(*regs));
  562         sf.sf_uc.uc_mcontext.mc_len = sizeof(sf.sf_uc.uc_mcontext); /* magic */
  563         get_fpcontext(td, &sf.sf_uc.uc_mcontext);
  564         fpstate_drop(td);
  565 
  566         /* Allocate space for the signal handler context. */
  567         if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack &&
  568             SIGISMEMBER(psp->ps_sigonstack, sig)) {
  569                 sp = td->td_sigstk.ss_sp +
  570                     td->td_sigstk.ss_size - sizeof(struct sigframe);
  571 #if defined(COMPAT_43)
  572                 td->td_sigstk.ss_flags |= SS_ONSTACK;
  573 #endif
  574         } else
  575                 sp = (char *)regs->tf_esp - sizeof(struct sigframe);
  576         /* Align to 16 bytes. */
  577         sfp = (struct sigframe *)((unsigned int)sp & ~0xF);
  578 
  579         /* Translate the signal if appropriate. */
  580         if (p->p_sysent->sv_sigtbl && sig <= p->p_sysent->sv_sigsize)
  581                 sig = p->p_sysent->sv_sigtbl[_SIG_IDX(sig)];
  582 
  583         /* Build the argument list for the signal handler. */
  584         sf.sf_signum = sig;
  585         sf.sf_ucontext = (register_t)&sfp->sf_uc;
  586         if (SIGISMEMBER(psp->ps_siginfo, sig)) {
  587                 /* Signal handler installed with SA_SIGINFO. */
  588                 sf.sf_siginfo = (register_t)&sfp->sf_si;
  589                 sf.sf_ahu.sf_action = (__siginfohandler_t *)catcher;
  590 
  591                 /* Fill in POSIX parts */
  592                 sf.sf_si = ksi->ksi_info;
  593                 sf.sf_si.si_signo = sig; /* maybe a translated signal */
  594         } else {
  595                 /* Old FreeBSD-style arguments. */
  596                 sf.sf_siginfo = ksi->ksi_code;
  597                 sf.sf_addr = (register_t)ksi->ksi_addr;
  598                 sf.sf_ahu.sf_handler = catcher;
  599         }
  600         mtx_unlock(&psp->ps_mtx);
  601         PROC_UNLOCK(p);
  602 
  603         /*
  604          * If we're a vm86 process, we want to save the segment registers.
  605          * We also change eflags to be our emulated eflags, not the actual
  606          * eflags.
  607          */
  608         if (regs->tf_eflags & PSL_VM) {
  609                 struct trapframe_vm86 *tf = (struct trapframe_vm86 *)regs;
  610                 struct vm86_kernel *vm86 = &td->td_pcb->pcb_ext->ext_vm86;
  611 
  612                 sf.sf_uc.uc_mcontext.mc_gs = tf->tf_vm86_gs;
  613                 sf.sf_uc.uc_mcontext.mc_fs = tf->tf_vm86_fs;
  614                 sf.sf_uc.uc_mcontext.mc_es = tf->tf_vm86_es;
  615                 sf.sf_uc.uc_mcontext.mc_ds = tf->tf_vm86_ds;
  616 
  617                 if (vm86->vm86_has_vme == 0)
  618                         sf.sf_uc.uc_mcontext.mc_eflags =
  619                             (tf->tf_eflags & ~(PSL_VIF | PSL_VIP)) |
  620                             (vm86->vm86_eflags & (PSL_VIF | PSL_VIP));
  621 
  622                 /*
  623                  * Clear PSL_NT to inhibit T_TSSFLT faults on return from
  624                  * syscalls made by the signal handler.  This just avoids
  625                  * wasting time for our lazy fixup of such faults.  PSL_NT
  626                  * does nothing in vm86 mode, but vm86 programs can set it
  627                  * almost legitimately in probes for old cpu types.
  628                  */
  629                 tf->tf_eflags &= ~(PSL_VM | PSL_NT | PSL_VIF | PSL_VIP);
  630         }
  631 
  632         /*
  633          * Copy the sigframe out to the user's stack.
  634          */
  635         if (copyout(&sf, sfp, sizeof(*sfp)) != 0) {
  636 #ifdef DEBUG
  637                 printf("process %ld has trashed its stack\n", (long)p->p_pid);
  638 #endif
  639                 PROC_LOCK(p);
  640                 sigexit(td, SIGILL);
  641         }
  642 
  643         regs->tf_esp = (int)sfp;
  644         regs->tf_eip = PS_STRINGS - *(p->p_sysent->sv_szsigcode);
  645         regs->tf_eflags &= ~(PSL_T | PSL_D);
  646         regs->tf_cs = _ucodesel;
  647         regs->tf_ds = _udatasel;
  648         regs->tf_es = _udatasel;
  649         regs->tf_fs = _udatasel;
  650         regs->tf_ss = _udatasel;
  651         PROC_LOCK(p);
  652         mtx_lock(&psp->ps_mtx);
  653 }
  654 
  655 /*
  656  * System call to cleanup state after a signal
  657  * has been taken.  Reset signal mask and
  658  * stack state from context left by sendsig (above).
  659  * Return to previous pc and psl as specified by
  660  * context left by sendsig. Check carefully to
  661  * make sure that the user has not modified the
  662  * state to gain improper privileges.
  663  *
  664  * MPSAFE
  665  */
  666 #ifdef COMPAT_43
  667 int
  668 osigreturn(td, uap)
  669         struct thread *td;
  670         struct osigreturn_args /* {
  671                 struct osigcontext *sigcntxp;
  672         } */ *uap;
  673 {
  674         struct osigcontext sc;
  675         struct trapframe *regs;
  676         struct osigcontext *scp;
  677         struct proc *p = td->td_proc;
  678         int eflags, error;
  679         ksiginfo_t ksi;
  680 
  681         regs = td->td_frame;
  682         error = copyin(uap->sigcntxp, &sc, sizeof(sc));
  683         if (error != 0)
  684                 return (error);
  685         scp = &sc;
  686         eflags = scp->sc_ps;
  687         if (eflags & PSL_VM) {
  688                 struct trapframe_vm86 *tf = (struct trapframe_vm86 *)regs;
  689                 struct vm86_kernel *vm86;
  690 
  691                 /*
  692                  * if pcb_ext == 0 or vm86_inited == 0, the user hasn't
  693                  * set up the vm86 area, and we can't enter vm86 mode.
  694                  */
  695                 if (td->td_pcb->pcb_ext == 0)
  696                         return (EINVAL);
  697                 vm86 = &td->td_pcb->pcb_ext->ext_vm86;
  698                 if (vm86->vm86_inited == 0)
  699                         return (EINVAL);
  700 
  701                 /* Go back to user mode if both flags are set. */
  702                 if ((eflags & PSL_VIP) && (eflags & PSL_VIF)) {
  703                         ksiginfo_init_trap(&ksi);
  704                         ksi.ksi_signo = SIGBUS;
  705                         ksi.ksi_code = BUS_OBJERR;
  706                         ksi.ksi_addr = (void *)regs->tf_eip;
  707                         trapsignal(td, &ksi);
  708                 }
  709 
  710                 if (vm86->vm86_has_vme) {
  711                         eflags = (tf->tf_eflags & ~VME_USERCHANGE) |
  712                             (eflags & VME_USERCHANGE) | PSL_VM;
  713                 } else {
  714                         vm86->vm86_eflags = eflags;     /* save VIF, VIP */
  715                         eflags = (tf->tf_eflags & ~VM_USERCHANGE) |
  716                             (eflags & VM_USERCHANGE) | PSL_VM;
  717                 }
  718                 tf->tf_vm86_ds = scp->sc_ds;
  719                 tf->tf_vm86_es = scp->sc_es;
  720                 tf->tf_vm86_fs = scp->sc_fs;
  721                 tf->tf_vm86_gs = scp->sc_gs;
  722                 tf->tf_ds = _udatasel;
  723                 tf->tf_es = _udatasel;
  724                 tf->tf_fs = _udatasel;
  725         } else {
  726                 /*
  727                  * Don't allow users to change privileged or reserved flags.
  728                  */
  729                 /*
  730                  * XXX do allow users to change the privileged flag PSL_RF.
  731                  * The cpu sets PSL_RF in tf_eflags for faults.  Debuggers
  732                  * should sometimes set it there too.  tf_eflags is kept in
  733                  * the signal context during signal handling and there is no
  734                  * other place to remember it, so the PSL_RF bit may be
  735                  * corrupted by the signal handler without us knowing.
  736                  * Corruption of the PSL_RF bit at worst causes one more or
  737                  * one less debugger trap, so allowing it is fairly harmless.
  738                  */
  739                 if (!EFL_SECURE(eflags & ~PSL_RF, regs->tf_eflags & ~PSL_RF)) {
  740                         return (EINVAL);
  741                 }
  742 
  743                 /*
  744                  * Don't allow users to load a valid privileged %cs.  Let the
  745                  * hardware check for invalid selectors, excess privilege in
  746                  * other selectors, invalid %eip's and invalid %esp's.
  747                  */
  748                 if (!CS_SECURE(scp->sc_cs)) {
  749                         ksiginfo_init_trap(&ksi);
  750                         ksi.ksi_signo = SIGBUS;
  751                         ksi.ksi_code = BUS_OBJERR;
  752                         ksi.ksi_trapno = T_PROTFLT;
  753                         ksi.ksi_addr = (void *)regs->tf_eip;
  754                         trapsignal(td, &ksi);
  755                         return (EINVAL);
  756                 }
  757                 regs->tf_ds = scp->sc_ds;
  758                 regs->tf_es = scp->sc_es;
  759                 regs->tf_fs = scp->sc_fs;
  760         }
  761 
  762         /* Restore remaining registers. */
  763         regs->tf_eax = scp->sc_eax;
  764         regs->tf_ebx = scp->sc_ebx;
  765         regs->tf_ecx = scp->sc_ecx;
  766         regs->tf_edx = scp->sc_edx;
  767         regs->tf_esi = scp->sc_esi;
  768         regs->tf_edi = scp->sc_edi;
  769         regs->tf_cs = scp->sc_cs;
  770         regs->tf_ss = scp->sc_ss;
  771         regs->tf_isp = scp->sc_isp;
  772         regs->tf_ebp = scp->sc_fp;
  773         regs->tf_esp = scp->sc_sp;
  774         regs->tf_eip = scp->sc_pc;
  775         regs->tf_eflags = eflags;
  776 
  777         PROC_LOCK(p);
  778 #if defined(COMPAT_43)
  779         if (scp->sc_onstack & 1)
  780                 td->td_sigstk.ss_flags |= SS_ONSTACK;
  781         else
  782                 td->td_sigstk.ss_flags &= ~SS_ONSTACK;
  783 #endif
  784         SIGSETOLD(td->td_sigmask, scp->sc_mask);
  785         SIG_CANTMASK(td->td_sigmask);
  786         signotify(td);
  787         PROC_UNLOCK(p);
  788         return (EJUSTRETURN);
  789 }
  790 #endif /* COMPAT_43 */
  791 
  792 #ifdef COMPAT_FREEBSD4
  793 /*
  794  * MPSAFE
  795  */
  796 int
  797 freebsd4_sigreturn(td, uap)
  798         struct thread *td;
  799         struct freebsd4_sigreturn_args /* {
  800                 const ucontext4 *sigcntxp;
  801         } */ *uap;
  802 {
  803         struct ucontext4 uc;
  804         struct proc *p = td->td_proc;
  805         struct trapframe *regs;
  806         const struct ucontext4 *ucp;
  807         int cs, eflags, error;
  808         ksiginfo_t ksi;
  809 
  810         error = copyin(uap->sigcntxp, &uc, sizeof(uc));
  811         if (error != 0)
  812                 return (error);
  813         ucp = &uc;
  814         regs = td->td_frame;
  815         eflags = ucp->uc_mcontext.mc_eflags;
  816         if (eflags & PSL_VM) {
  817                 struct trapframe_vm86 *tf = (struct trapframe_vm86 *)regs;
  818                 struct vm86_kernel *vm86;
  819 
  820                 /*
  821                  * if pcb_ext == 0 or vm86_inited == 0, the user hasn't
  822                  * set up the vm86 area, and we can't enter vm86 mode.
  823                  */
  824                 if (td->td_pcb->pcb_ext == 0)
  825                         return (EINVAL);
  826                 vm86 = &td->td_pcb->pcb_ext->ext_vm86;
  827                 if (vm86->vm86_inited == 0)
  828                         return (EINVAL);
  829 
  830                 /* Go back to user mode if both flags are set. */
  831                 if ((eflags & PSL_VIP) && (eflags & PSL_VIF)) {
  832                         ksiginfo_init_trap(&ksi);
  833                         ksi.ksi_signo = SIGBUS;
  834                         ksi.ksi_code = BUS_OBJERR;
  835                         ksi.ksi_addr = (void *)regs->tf_eip;
  836                         trapsignal(td, &ksi);
  837                 }
  838                 if (vm86->vm86_has_vme) {
  839                         eflags = (tf->tf_eflags & ~VME_USERCHANGE) |
  840                             (eflags & VME_USERCHANGE) | PSL_VM;
  841                 } else {
  842                         vm86->vm86_eflags = eflags;     /* save VIF, VIP */
  843                         eflags = (tf->tf_eflags & ~VM_USERCHANGE) |
  844                             (eflags & VM_USERCHANGE) | PSL_VM;
  845                 }
  846                 bcopy(&ucp->uc_mcontext.mc_fs, tf, sizeof(struct trapframe));
  847                 tf->tf_eflags = eflags;
  848                 tf->tf_vm86_ds = tf->tf_ds;
  849                 tf->tf_vm86_es = tf->tf_es;
  850                 tf->tf_vm86_fs = tf->tf_fs;
  851                 tf->tf_vm86_gs = ucp->uc_mcontext.mc_gs;
  852                 tf->tf_ds = _udatasel;
  853                 tf->tf_es = _udatasel;
  854                 tf->tf_fs = _udatasel;
  855         } else {
  856                 /*
  857                  * Don't allow users to change privileged or reserved flags.
  858                  */
  859                 /*
  860                  * XXX do allow users to change the privileged flag PSL_RF.
  861                  * The cpu sets PSL_RF in tf_eflags for faults.  Debuggers
  862                  * should sometimes set it there too.  tf_eflags is kept in
  863                  * the signal context during signal handling and there is no
  864                  * other place to remember it, so the PSL_RF bit may be
  865                  * corrupted by the signal handler without us knowing.
  866                  * Corruption of the PSL_RF bit at worst causes one more or
  867                  * one less debugger trap, so allowing it is fairly harmless.
  868                  */
  869                 if (!EFL_SECURE(eflags & ~PSL_RF, regs->tf_eflags & ~PSL_RF)) {
  870                         printf("freebsd4_sigreturn: eflags = 0x%x\n", eflags);
  871                         return (EINVAL);
  872                 }
  873 
  874                 /*
  875                  * Don't allow users to load a valid privileged %cs.  Let the
  876                  * hardware check for invalid selectors, excess privilege in
  877                  * other selectors, invalid %eip's and invalid %esp's.
  878                  */
  879                 cs = ucp->uc_mcontext.mc_cs;
  880                 if (!CS_SECURE(cs)) {
  881                         printf("freebsd4_sigreturn: cs = 0x%x\n", cs);
  882                         ksiginfo_init_trap(&ksi);
  883                         ksi.ksi_signo = SIGBUS;
  884                         ksi.ksi_code = BUS_OBJERR;
  885                         ksi.ksi_trapno = T_PROTFLT;
  886                         ksi.ksi_addr = (void *)regs->tf_eip;
  887                         trapsignal(td, &ksi);
  888                         return (EINVAL);
  889                 }
  890 
  891                 bcopy(&ucp->uc_mcontext.mc_fs, regs, sizeof(*regs));
  892         }
  893 
  894         PROC_LOCK(p);
  895 #if defined(COMPAT_43)
  896         if (ucp->uc_mcontext.mc_onstack & 1)
  897                 td->td_sigstk.ss_flags |= SS_ONSTACK;
  898         else
  899                 td->td_sigstk.ss_flags &= ~SS_ONSTACK;
  900 #endif
  901 
  902         td->td_sigmask = ucp->uc_sigmask;
  903         SIG_CANTMASK(td->td_sigmask);
  904         signotify(td);
  905         PROC_UNLOCK(p);
  906         return (EJUSTRETURN);
  907 }
  908 #endif  /* COMPAT_FREEBSD4 */
  909 
  910 /*
  911  * MPSAFE
  912  */
  913 int
  914 sigreturn(td, uap)
  915         struct thread *td;
  916         struct sigreturn_args /* {
  917                 const struct __ucontext *sigcntxp;
  918         } */ *uap;
  919 {
  920         ucontext_t uc;
  921         struct proc *p = td->td_proc;
  922         struct trapframe *regs;
  923         const ucontext_t *ucp;
  924         int cs, eflags, error, ret;
  925         ksiginfo_t ksi;
  926 
  927         error = copyin(uap->sigcntxp, &uc, sizeof(uc));
  928         if (error != 0)
  929                 return (error);
  930         ucp = &uc;
  931         regs = td->td_frame;
  932         eflags = ucp->uc_mcontext.mc_eflags;
  933         if (eflags & PSL_VM) {
  934                 struct trapframe_vm86 *tf = (struct trapframe_vm86 *)regs;
  935                 struct vm86_kernel *vm86;
  936 
  937                 /*
  938                  * if pcb_ext == 0 or vm86_inited == 0, the user hasn't
  939                  * set up the vm86 area, and we can't enter vm86 mode.
  940                  */
  941                 if (td->td_pcb->pcb_ext == 0)
  942                         return (EINVAL);
  943                 vm86 = &td->td_pcb->pcb_ext->ext_vm86;
  944                 if (vm86->vm86_inited == 0)
  945                         return (EINVAL);
  946 
  947                 /* Go back to user mode if both flags are set. */
  948                 if ((eflags & PSL_VIP) && (eflags & PSL_VIF)) {
  949                         ksiginfo_init_trap(&ksi);
  950                         ksi.ksi_signo = SIGBUS;
  951                         ksi.ksi_code = BUS_OBJERR;
  952                         ksi.ksi_addr = (void *)regs->tf_eip;
  953                         trapsignal(td, &ksi);
  954                 }
  955 
  956                 if (vm86->vm86_has_vme) {
  957                         eflags = (tf->tf_eflags & ~VME_USERCHANGE) |
  958                             (eflags & VME_USERCHANGE) | PSL_VM;
  959                 } else {
  960                         vm86->vm86_eflags = eflags;     /* save VIF, VIP */
  961                         eflags = (tf->tf_eflags & ~VM_USERCHANGE) |
  962                             (eflags & VM_USERCHANGE) | PSL_VM;
  963                 }
  964                 bcopy(&ucp->uc_mcontext.mc_fs, tf, sizeof(struct trapframe));
  965                 tf->tf_eflags = eflags;
  966                 tf->tf_vm86_ds = tf->tf_ds;
  967                 tf->tf_vm86_es = tf->tf_es;
  968                 tf->tf_vm86_fs = tf->tf_fs;
  969                 tf->tf_vm86_gs = ucp->uc_mcontext.mc_gs;
  970                 tf->tf_ds = _udatasel;
  971                 tf->tf_es = _udatasel;
  972                 tf->tf_fs = _udatasel;
  973         } else {
  974                 /*
  975                  * Don't allow users to change privileged or reserved flags.
  976                  */
  977                 /*
  978                  * XXX do allow users to change the privileged flag PSL_RF.
  979                  * The cpu sets PSL_RF in tf_eflags for faults.  Debuggers
  980                  * should sometimes set it there too.  tf_eflags is kept in
  981                  * the signal context during signal handling and there is no
  982                  * other place to remember it, so the PSL_RF bit may be
  983                  * corrupted by the signal handler without us knowing.
  984                  * Corruption of the PSL_RF bit at worst causes one more or
  985                  * one less debugger trap, so allowing it is fairly harmless.
  986                  */
  987                 if (!EFL_SECURE(eflags & ~PSL_RF, regs->tf_eflags & ~PSL_RF)) {
  988                         printf("sigreturn: eflags = 0x%x\n", eflags);
  989                         return (EINVAL);
  990                 }
  991 
  992                 /*
  993                  * Don't allow users to load a valid privileged %cs.  Let the
  994                  * hardware check for invalid selectors, excess privilege in
  995                  * other selectors, invalid %eip's and invalid %esp's.
  996                  */
  997                 cs = ucp->uc_mcontext.mc_cs;
  998                 if (!CS_SECURE(cs)) {
  999                         printf("sigreturn: cs = 0x%x\n", cs);
 1000                         ksiginfo_init_trap(&ksi);
 1001                         ksi.ksi_signo = SIGBUS;
 1002                         ksi.ksi_code = BUS_OBJERR;
 1003                         ksi.ksi_trapno = T_PROTFLT;
 1004                         ksi.ksi_addr = (void *)regs->tf_eip;
 1005                         trapsignal(td, &ksi);
 1006                         return (EINVAL);
 1007                 }
 1008 
 1009                 ret = set_fpcontext(td, &ucp->uc_mcontext);
 1010                 if (ret != 0)
 1011                         return (ret);
 1012                 bcopy(&ucp->uc_mcontext.mc_fs, regs, sizeof(*regs));
 1013         }
 1014 
 1015         PROC_LOCK(p);
 1016 #if defined(COMPAT_43)
 1017         if (ucp->uc_mcontext.mc_onstack & 1)
 1018                 td->td_sigstk.ss_flags |= SS_ONSTACK;
 1019         else
 1020                 td->td_sigstk.ss_flags &= ~SS_ONSTACK;
 1021 #endif
 1022 
 1023         td->td_sigmask = ucp->uc_sigmask;
 1024         SIG_CANTMASK(td->td_sigmask);
 1025         signotify(td);
 1026         PROC_UNLOCK(p);
 1027         return (EJUSTRETURN);
 1028 }
 1029 
 1030 /*
 1031  * Machine dependent boot() routine
 1032  *
 1033  * I haven't seen anything to put here yet
 1034  * Possibly some stuff might be grafted back here from boot()
 1035  */
 1036 void
 1037 cpu_boot(int howto)
 1038 {
 1039 }
 1040 
 1041 /* Get current clock frequency for the given cpu id. */
 1042 int
 1043 cpu_est_clockrate(int cpu_id, uint64_t *rate)
 1044 {
 1045         register_t reg;
 1046         uint64_t tsc1, tsc2;
 1047 
 1048         if (pcpu_find(cpu_id) == NULL || rate == NULL)
 1049                 return (EINVAL);
 1050         if (!tsc_present)
 1051                 return (EOPNOTSUPP);
 1052 
 1053         /* If we're booting, trust the rate calibrated moments ago. */
 1054         if (cold) {
 1055                 *rate = tsc_freq;
 1056                 return (0);
 1057         }
 1058 
 1059 #ifdef SMP
 1060         /* Schedule ourselves on the indicated cpu. */
 1061         thread_lock(curthread);
 1062         sched_bind(curthread, cpu_id);
 1063         thread_unlock(curthread);
 1064 #endif
 1065 
 1066         /* Calibrate by measuring a short delay. */
 1067         reg = intr_disable();
 1068         tsc1 = rdtsc();
 1069         DELAY(1000);
 1070         tsc2 = rdtsc();
 1071         intr_restore(reg);
 1072 
 1073 #ifdef SMP
 1074         thread_lock(curthread);
 1075         sched_unbind(curthread);
 1076         thread_unlock(curthread);
 1077 #endif
 1078 
 1079         /*
 1080          * Calculate the difference in readings, convert to Mhz, and
 1081          * subtract 0.5% of the total.  Empirical testing has shown that
 1082          * overhead in DELAY() works out to approximately this value.
 1083          */
 1084         tsc2 -= tsc1;
 1085         *rate = tsc2 * 1000 - tsc2 * 5;
 1086         return (0);
 1087 }
 1088 
 1089 /*
 1090  * Shutdown the CPU as much as possible
 1091  */
 1092 void
 1093 cpu_halt(void)
 1094 {
 1095         for (;;)
 1096                 __asm__ ("hlt");
 1097 }
 1098 
 1099 /*
 1100  * Hook to idle the CPU when possible.  In the SMP case we default to
 1101  * off because a halted cpu will not currently pick up a new thread in the
 1102  * run queue until the next timer tick.  If turned on this will result in
 1103  * approximately a 4.2% loss in real time performance in buildworld tests
 1104  * (but improves user and sys times oddly enough), and saves approximately
 1105  * 5% in power consumption on an idle machine (tests w/2xCPU 1.1GHz P3).
 1106  *
 1107  * XXX we need to have a cpu mask of idle cpus and generate an IPI or
 1108  * otherwise generate some sort of interrupt to wake up cpus sitting in HLT.
 1109  * Then we can have our cake and eat it too.
 1110  *
 1111  * XXX I'm turning it on for SMP as well by default for now.  It seems to
 1112  * help lock contention somewhat, and this is critical for HTT. -Peter
 1113  */
 1114 static int      cpu_idle_hlt = 1;
 1115 TUNABLE_INT("machdep.cpu_idle_hlt", &cpu_idle_hlt);
 1116 SYSCTL_INT(_machdep, OID_AUTO, cpu_idle_hlt, CTLFLAG_RW,
 1117     &cpu_idle_hlt, 0, "Idle loop HLT enable");
 1118 
 1119 static void
 1120 cpu_idle_default(void)
 1121 {
 1122         /*
 1123          * we must absolutely guarentee that hlt is the
 1124          * absolute next instruction after sti or we
 1125          * introduce a timing window.
 1126          */
 1127         __asm __volatile("sti; hlt");
 1128 }
 1129 
 1130 /*
 1131  * Note that we have to be careful here to avoid a race between checking
 1132  * sched_runnable() and actually halting.  If we don't do this, we may waste
 1133  * the time between calling hlt and the next interrupt even though there
 1134  * is a runnable process.
 1135  */
 1136 void
 1137 cpu_idle(void)
 1138 {
 1139 
 1140 #ifdef SMP
 1141         if (mp_grab_cpu_hlt())
 1142                 return;
 1143 #endif
 1144 
 1145         if (cpu_idle_hlt) {
 1146                 disable_intr();
 1147                 if (sched_runnable())
 1148                         enable_intr();
 1149                 else
 1150                         (*cpu_idle_hook)();
 1151         }
 1152 }
 1153 
 1154 /* Other subsystems (e.g., ACPI) can hook this later. */
 1155 void (*cpu_idle_hook)(void) = cpu_idle_default;
 1156 
 1157 /*
 1158  * Clear registers on exec
 1159  */
 1160 void
 1161 exec_setregs(td, entry, stack, ps_strings)
 1162         struct thread *td;
 1163         u_long entry;
 1164         u_long stack;
 1165         u_long ps_strings;
 1166 {
 1167         struct trapframe *regs = td->td_frame;
 1168         struct pcb *pcb = td->td_pcb;
 1169 
 1170         /* Reset pc->pcb_gs and %gs before possibly invalidating it. */
 1171         pcb->pcb_gs = _udatasel;
 1172         load_gs(_udatasel);
 1173 
 1174         mtx_lock_spin(&dt_lock);
 1175         if (td->td_proc->p_md.md_ldt)
 1176                 user_ldt_free(td);
 1177         else
 1178                 mtx_unlock_spin(&dt_lock);
 1179   
 1180         bzero((char *)regs, sizeof(struct trapframe));
 1181         regs->tf_eip = entry;
 1182         regs->tf_esp = stack;
 1183         regs->tf_eflags = PSL_USER | (regs->tf_eflags & PSL_T);
 1184         regs->tf_ss = _udatasel;
 1185         regs->tf_ds = _udatasel;
 1186         regs->tf_es = _udatasel;
 1187         regs->tf_fs = _udatasel;
 1188         regs->tf_cs = _ucodesel;
 1189 
 1190         /* PS_STRINGS value for BSD/OS binaries.  It is 0 for non-BSD/OS. */
 1191         regs->tf_ebx = ps_strings;
 1192 
 1193         /*
 1194          * Reset the hardware debug registers if they were in use.
 1195          * They won't have any meaning for the newly exec'd process.  
 1196          */
 1197         if (pcb->pcb_flags & PCB_DBREGS) {
 1198                 pcb->pcb_dr0 = 0;
 1199                 pcb->pcb_dr1 = 0;
 1200                 pcb->pcb_dr2 = 0;
 1201                 pcb->pcb_dr3 = 0;
 1202                 pcb->pcb_dr6 = 0;
 1203                 pcb->pcb_dr7 = 0;
 1204                 if (pcb == PCPU_GET(curpcb)) {
 1205                         /*
 1206                          * Clear the debug registers on the running
 1207                          * CPU, otherwise they will end up affecting
 1208                          * the next process we switch to.
 1209                          */
 1210                         reset_dbregs();
 1211                 }
 1212                 pcb->pcb_flags &= ~PCB_DBREGS;
 1213         }
 1214 
 1215         /*
 1216          * Initialize the math emulator (if any) for the current process.
 1217          * Actually, just clear the bit that says that the emulator has
 1218          * been initialized.  Initialization is delayed until the process
 1219          * traps to the emulator (if it is done at all) mainly because
 1220          * emulators don't provide an entry point for initialization.
 1221          */
 1222         td->td_pcb->pcb_flags &= ~FP_SOFTFP;
 1223 
 1224         /*
 1225          * Drop the FP state if we hold it, so that the process gets a
 1226          * clean FP state if it uses the FPU again.
 1227          */
 1228         fpstate_drop(td);
 1229 
 1230         /*
 1231          * XXX - Linux emulator
 1232          * Make sure sure edx is 0x0 on entry. Linux binaries depend
 1233          * on it.
 1234          */
 1235         td->td_retval[1] = 0;
 1236 }
 1237 
 1238 void
 1239 cpu_setregs(void)
 1240 {
 1241         unsigned int cr0;
 1242 
 1243         cr0 = rcr0();
 1244 
 1245         /*
 1246          * CR0_MP, CR0_NE and CR0_TS are set for NPX (FPU) support:
 1247          *
 1248          * Prepare to trap all ESC (i.e., NPX) instructions and all WAIT
 1249          * instructions.  We must set the CR0_MP bit and use the CR0_TS
 1250          * bit to control the trap, because setting the CR0_EM bit does
 1251          * not cause WAIT instructions to trap.  It's important to trap
 1252          * WAIT instructions - otherwise the "wait" variants of no-wait
 1253          * control instructions would degenerate to the "no-wait" variants
 1254          * after FP context switches but work correctly otherwise.  It's
 1255          * particularly important to trap WAITs when there is no NPX -
 1256          * otherwise the "wait" variants would always degenerate.
 1257          *
 1258          * Try setting CR0_NE to get correct error reporting on 486DX's.
 1259          * Setting it should fail or do nothing on lesser processors.
 1260          */
 1261         cr0 |= CR0_MP | CR0_NE | CR0_TS | CR0_WP | CR0_AM;
 1262         load_cr0(cr0);
 1263         load_gs(_udatasel);
 1264 }
 1265 
 1266 u_long bootdev;         /* not a struct cdev *- encoding is different */
 1267 SYSCTL_ULONG(_machdep, OID_AUTO, guessed_bootdev,
 1268         CTLFLAG_RD, &bootdev, 0, "Maybe the Boot device (not in struct cdev *format)");
 1269 
 1270 /*
 1271  * Initialize 386 and configure to run kernel
 1272  */
 1273 
 1274 /*
 1275  * Initialize segments & interrupt table
 1276  */
 1277 
 1278 int _default_ldt;
 1279 union descriptor gdt[NGDT * MAXCPU];    /* global descriptor table */
 1280 static struct gate_descriptor idt0[NIDT];
 1281 struct gate_descriptor *idt = &idt0[0]; /* interrupt descriptor table */
 1282 union descriptor ldt[NLDT];             /* local descriptor table */
 1283 struct region_descriptor r_gdt, r_idt;  /* table descriptors */
 1284 struct mtx dt_lock;                     /* lock for GDT and LDT */
 1285 
 1286 #if defined(I586_CPU) && !defined(NO_F00F_HACK)
 1287 extern int has_f00f_bug;
 1288 #endif
 1289 
 1290 static struct i386tss dblfault_tss;
 1291 static char dblfault_stack[PAGE_SIZE];
 1292 
 1293 extern  vm_offset_t     proc0kstack;
 1294 
 1295 
 1296 /*
 1297  * software prototypes -- in more palatable form.
 1298  *
 1299  * GCODE_SEL through GUDATA_SEL must be in this order for syscall/sysret
 1300  * GUFS_SEL and GUGS_SEL must be in this order (swtch.s knows it)
 1301  */
 1302 struct soft_segment_descriptor gdt_segs[] = {
 1303 /* GNULL_SEL    0 Null Descriptor */
 1304 {       0x0,                    /* segment base address  */
 1305         0x0,                    /* length */
 1306         0,                      /* segment type */
 1307         0,                      /* segment descriptor priority level */
 1308         0,                      /* segment descriptor present */
 1309         0, 0,
 1310         0,                      /* default 32 vs 16 bit size */
 1311         0                       /* limit granularity (byte/page units)*/ },
 1312 /* GPRIV_SEL    1 SMP Per-Processor Private Data Descriptor */
 1313 {       0x0,                    /* segment base address  */
 1314         0xfffff,                /* length - all address space */
 1315         SDT_MEMRWA,             /* segment type */
 1316         0,                      /* segment descriptor priority level */
 1317         1,                      /* segment descriptor present */
 1318         0, 0,
 1319         1,                      /* default 32 vs 16 bit size */
 1320         1                       /* limit granularity (byte/page units)*/ },
 1321 /* GUFS_SEL     2 %fs Descriptor for user */
 1322 {       0x0,                    /* segment base address  */
 1323         0xfffff,                /* length - all address space */
 1324         SDT_MEMRWA,             /* segment type */
 1325         SEL_UPL,                /* segment descriptor priority level */
 1326         1,                      /* segment descriptor present */
 1327         0, 0,
 1328         1,                      /* default 32 vs 16 bit size */
 1329         1                       /* limit granularity (byte/page units)*/ },
 1330 /* GUGS_SEL     3 %gs Descriptor for user */
 1331 {       0x0,                    /* segment base address  */
 1332         0xfffff,                /* length - all address space */
 1333         SDT_MEMRWA,             /* segment type */
 1334         SEL_UPL,                /* segment descriptor priority level */
 1335         1,                      /* segment descriptor present */
 1336         0, 0,
 1337         1,                      /* default 32 vs 16 bit size */
 1338         1                       /* limit granularity (byte/page units)*/ },
 1339 /* GCODE_SEL    4 Code Descriptor for kernel */
 1340 {       0x0,                    /* segment base address  */
 1341         0xfffff,                /* length - all address space */
 1342         SDT_MEMERA,             /* segment type */
 1343         0,                      /* segment descriptor priority level */
 1344         1,                      /* segment descriptor present */
 1345         0, 0,
 1346         1,                      /* default 32 vs 16 bit size */
 1347         1                       /* limit granularity (byte/page units)*/ },
 1348 /* GDATA_SEL    5 Data Descriptor for kernel */
 1349 {       0x0,                    /* segment base address  */
 1350         0xfffff,                /* length - all address space */
 1351         SDT_MEMRWA,             /* segment type */
 1352         0,                      /* segment descriptor priority level */
 1353         1,                      /* segment descriptor present */
 1354         0, 0,
 1355         1,                      /* default 32 vs 16 bit size */
 1356         1                       /* limit granularity (byte/page units)*/ },
 1357 /* GUCODE_SEL   6 Code Descriptor for user */
 1358 {       0x0,                    /* segment base address  */
 1359         0xfffff,                /* length - all address space */
 1360         SDT_MEMERA,             /* segment type */
 1361         SEL_UPL,                /* segment descriptor priority level */
 1362         1,                      /* segment descriptor present */
 1363         0, 0,
 1364         1,                      /* default 32 vs 16 bit size */
 1365         1                       /* limit granularity (byte/page units)*/ },
 1366 /* GUDATA_SEL   7 Data Descriptor for user */
 1367 {       0x0,                    /* segment base address  */
 1368         0xfffff,                /* length - all address space */
 1369         SDT_MEMRWA,             /* segment type */
 1370         SEL_UPL,                /* segment descriptor priority level */
 1371         1,                      /* segment descriptor present */
 1372         0, 0,
 1373         1,                      /* default 32 vs 16 bit size */
 1374         1                       /* limit granularity (byte/page units)*/ },
 1375 /* GBIOSLOWMEM_SEL 8 BIOS access to realmode segment 0x40, must be #8 in GDT */
 1376 {       0x400,                  /* segment base address */
 1377         0xfffff,                /* length */
 1378         SDT_MEMRWA,             /* segment type */
 1379         0,                      /* segment descriptor priority level */
 1380         1,                      /* segment descriptor present */
 1381         0, 0,
 1382         1,                      /* default 32 vs 16 bit size */
 1383         1                       /* limit granularity (byte/page units)*/ },
 1384 /* GPROC0_SEL   9 Proc 0 Tss Descriptor */
 1385 {
 1386         0x0,                    /* segment base address */
 1387         sizeof(struct i386tss)-1,/* length  */
 1388         SDT_SYS386TSS,          /* segment type */
 1389         0,                      /* segment descriptor priority level */
 1390         1,                      /* segment descriptor present */
 1391         0, 0,
 1392         0,                      /* unused - default 32 vs 16 bit size */
 1393         0                       /* limit granularity (byte/page units)*/ },
 1394 /* GLDT_SEL     10 LDT Descriptor */
 1395 {       (int) ldt,              /* segment base address  */
 1396         sizeof(ldt)-1,          /* length - all address space */
 1397         SDT_SYSLDT,             /* segment type */
 1398         SEL_UPL,                /* segment descriptor priority level */
 1399         1,                      /* segment descriptor present */
 1400         0, 0,
 1401         0,                      /* unused - default 32 vs 16 bit size */
 1402         0                       /* limit granularity (byte/page units)*/ },
 1403 /* GUSERLDT_SEL 11 User LDT Descriptor per process */
 1404 {       (int) ldt,              /* segment base address  */
 1405         (512 * sizeof(union descriptor)-1),             /* length */
 1406         SDT_SYSLDT,             /* segment type */
 1407         0,                      /* segment descriptor priority level */
 1408         1,                      /* segment descriptor present */
 1409         0, 0,
 1410         0,                      /* unused - default 32 vs 16 bit size */
 1411         0                       /* limit granularity (byte/page units)*/ },
 1412 /* GPANIC_SEL   12 Panic Tss Descriptor */
 1413 {       (int) &dblfault_tss,    /* segment base address  */
 1414         sizeof(struct i386tss)-1,/* length - all address space */
 1415         SDT_SYS386TSS,          /* segment type */
 1416         0,                      /* segment descriptor priority level */
 1417         1,                      /* segment descriptor present */
 1418         0, 0,
 1419         0,                      /* unused - default 32 vs 16 bit size */
 1420         0                       /* limit granularity (byte/page units)*/ },
 1421 /* GBIOSCODE32_SEL 13 BIOS 32-bit interface (32bit Code) */
 1422 {       0,                      /* segment base address (overwritten)  */
 1423         0xfffff,                /* length */
 1424         SDT_MEMERA,             /* segment type */
 1425         0,                      /* segment descriptor priority level */
 1426         1,                      /* segment descriptor present */
 1427         0, 0,
 1428         0,                      /* default 32 vs 16 bit size */
 1429         1                       /* limit granularity (byte/page units)*/ },
 1430 /* GBIOSCODE16_SEL 14 BIOS 32-bit interface (16bit Code) */
 1431 {       0,                      /* segment base address (overwritten)  */
 1432         0xfffff,                /* length */
 1433         SDT_MEMERA,             /* segment type */
 1434         0,                      /* segment descriptor priority level */
 1435         1,                      /* segment descriptor present */
 1436         0, 0,
 1437         0,                      /* default 32 vs 16 bit size */
 1438         1                       /* limit granularity (byte/page units)*/ },
 1439 /* GBIOSDATA_SEL 15 BIOS 32-bit interface (Data) */
 1440 {       0,                      /* segment base address (overwritten) */
 1441         0xfffff,                /* length */
 1442         SDT_MEMRWA,             /* segment type */
 1443         0,                      /* segment descriptor priority level */
 1444         1,                      /* segment descriptor present */
 1445         0, 0,
 1446         1,                      /* default 32 vs 16 bit size */
 1447         1                       /* limit granularity (byte/page units)*/ },
 1448 /* GBIOSUTIL_SEL 16 BIOS 16-bit interface (Utility) */
 1449 {       0,                      /* segment base address (overwritten) */
 1450         0xfffff,                /* length */
 1451         SDT_MEMRWA,             /* segment type */
 1452         0,                      /* segment descriptor priority level */
 1453         1,                      /* segment descriptor present */
 1454         0, 0,
 1455         0,                      /* default 32 vs 16 bit size */
 1456         1                       /* limit granularity (byte/page units)*/ },
 1457 /* GBIOSARGS_SEL 17 BIOS 16-bit interface (Arguments) */
 1458 {       0,                      /* segment base address (overwritten) */
 1459         0xfffff,                /* length */
 1460         SDT_MEMRWA,             /* segment type */
 1461         0,                      /* segment descriptor priority level */
 1462         1,                      /* segment descriptor present */
 1463         0, 0,
 1464         0,                      /* default 32 vs 16 bit size */
 1465         1                       /* limit granularity (byte/page units)*/ },
 1466 /* GNDIS_SEL    18 NDIS Descriptor */
 1467 {       0x0,                    /* segment base address  */
 1468         0x0,                    /* length */
 1469         0,                      /* segment type */
 1470         0,                      /* segment descriptor priority level */
 1471         0,                      /* segment descriptor present */
 1472         0, 0,
 1473         0,                      /* default 32 vs 16 bit size */
 1474         0                       /* limit granularity (byte/page units)*/ },
 1475 };
 1476 
 1477 static struct soft_segment_descriptor ldt_segs[] = {
 1478         /* Null Descriptor - overwritten by call gate */
 1479 {       0x0,                    /* segment base address  */
 1480         0x0,                    /* length - all address space */
 1481         0,                      /* segment type */
 1482         0,                      /* segment descriptor priority level */
 1483         0,                      /* segment descriptor present */
 1484         0, 0,
 1485         0,                      /* default 32 vs 16 bit size */
 1486         0                       /* limit granularity (byte/page units)*/ },
 1487         /* Null Descriptor - overwritten by call gate */
 1488 {       0x0,                    /* segment base address  */
 1489         0x0,                    /* length - all address space */
 1490         0,                      /* segment type */
 1491         0,                      /* segment descriptor priority level */
 1492         0,                      /* segment descriptor present */
 1493         0, 0,
 1494         0,                      /* default 32 vs 16 bit size */
 1495         0                       /* limit granularity (byte/page units)*/ },
 1496         /* Null Descriptor - overwritten by call gate */
 1497 {       0x0,                    /* segment base address  */
 1498         0x0,                    /* length - all address space */
 1499         0,                      /* segment type */
 1500         0,                      /* segment descriptor priority level */
 1501         0,                      /* segment descriptor present */
 1502         0, 0,
 1503         0,                      /* default 32 vs 16 bit size */
 1504         0                       /* limit granularity (byte/page units)*/ },
 1505         /* Code Descriptor for user */
 1506 {       0x0,                    /* segment base address  */
 1507         0xfffff,                /* length - all address space */
 1508         SDT_MEMERA,             /* segment type */
 1509         SEL_UPL,                /* segment descriptor priority level */
 1510         1,                      /* segment descriptor present */
 1511         0, 0,
 1512         1,                      /* default 32 vs 16 bit size */
 1513         1                       /* limit granularity (byte/page units)*/ },
 1514         /* Null Descriptor - overwritten by call gate */
 1515 {       0x0,                    /* segment base address  */
 1516         0x0,                    /* length - all address space */
 1517         0,                      /* segment type */
 1518         0,                      /* segment descriptor priority level */
 1519         0,                      /* segment descriptor present */
 1520         0, 0,
 1521         0,                      /* default 32 vs 16 bit size */
 1522         0                       /* limit granularity (byte/page units)*/ },
 1523         /* Data Descriptor for user */
 1524 {       0x0,                    /* segment base address  */
 1525         0xfffff,                /* length - all address space */
 1526         SDT_MEMRWA,             /* segment type */
 1527         SEL_UPL,                /* segment descriptor priority level */
 1528         1,                      /* segment descriptor present */
 1529         0, 0,
 1530         1,                      /* default 32 vs 16 bit size */
 1531         1                       /* limit granularity (byte/page units)*/ },
 1532 };
 1533 
 1534 void
 1535 setidt(idx, func, typ, dpl, selec)
 1536         int idx;
 1537         inthand_t *func;
 1538         int typ;
 1539         int dpl;
 1540         int selec;
 1541 {
 1542         struct gate_descriptor *ip;
 1543 
 1544         ip = idt + idx;
 1545         ip->gd_looffset = (int)func;
 1546         ip->gd_selector = selec;
 1547         ip->gd_stkcpy = 0;
 1548         ip->gd_xx = 0;
 1549         ip->gd_type = typ;
 1550         ip->gd_dpl = dpl;
 1551         ip->gd_p = 1;
 1552         ip->gd_hioffset = ((int)func)>>16 ;
 1553 }
 1554 
 1555 extern inthand_t
 1556         IDTVEC(div), IDTVEC(dbg), IDTVEC(nmi), IDTVEC(bpt), IDTVEC(ofl),
 1557         IDTVEC(bnd), IDTVEC(ill), IDTVEC(dna), IDTVEC(fpusegm),
 1558         IDTVEC(tss), IDTVEC(missing), IDTVEC(stk), IDTVEC(prot),
 1559         IDTVEC(page), IDTVEC(mchk), IDTVEC(rsvd), IDTVEC(fpu), IDTVEC(align),
 1560         IDTVEC(xmm), IDTVEC(lcall_syscall), IDTVEC(int0x80_syscall);
 1561 
 1562 #ifdef DDB
 1563 /*
 1564  * Display the index and function name of any IDT entries that don't use
 1565  * the default 'rsvd' entry point.
 1566  */
 1567 DB_SHOW_COMMAND(idt, db_show_idt)
 1568 {
 1569         struct gate_descriptor *ip;
 1570         int idx;
 1571         uintptr_t func;
 1572 
 1573         ip = idt;
 1574         for (idx = 0; idx < NIDT && !db_pager_quit; idx++) {
 1575                 func = (ip->gd_hioffset << 16 | ip->gd_looffset);
 1576                 if (func != (uintptr_t)&IDTVEC(rsvd)) {
 1577                         db_printf("%3d\t", idx);
 1578                         db_printsym(func, DB_STGY_PROC);
 1579                         db_printf("\n");
 1580                 }
 1581                 ip++;
 1582         }
 1583 }
 1584 
 1585 /* Show privileged registers. */
 1586 DB_SHOW_COMMAND(sysregs, db_show_sysregs)
 1587 {
 1588         uint64_t idtr, gdtr;
 1589 
 1590         idtr = ridt();
 1591         db_printf("idtr\t0x%08x/%04x\n",
 1592             (u_int)(idtr >> 16), (u_int)idtr & 0xffff);
 1593         gdtr = rgdt();
 1594         db_printf("gdtr\t0x%08x/%04x\n",
 1595             (u_int)(gdtr >> 16), (u_int)gdtr & 0xffff);
 1596         db_printf("ldtr\t0x%04x\n", rldt());
 1597         db_printf("tr\t0x%04x\n", rtr());
 1598         db_printf("cr0\t0x%08x\n", rcr0());
 1599         db_printf("cr2\t0x%08x\n", rcr2());
 1600         db_printf("cr3\t0x%08x\n", rcr3());
 1601         db_printf("cr4\t0x%08x\n", rcr4());
 1602 }
 1603 #endif
 1604 
 1605 void
 1606 sdtossd(sd, ssd)
 1607         struct segment_descriptor *sd;
 1608         struct soft_segment_descriptor *ssd;
 1609 {
 1610         ssd->ssd_base  = (sd->sd_hibase << 24) | sd->sd_lobase;
 1611         ssd->ssd_limit = (sd->sd_hilimit << 16) | sd->sd_lolimit;
 1612         ssd->ssd_type  = sd->sd_type;
 1613         ssd->ssd_dpl   = sd->sd_dpl;
 1614         ssd->ssd_p     = sd->sd_p;
 1615         ssd->ssd_def32 = sd->sd_def32;
 1616         ssd->ssd_gran  = sd->sd_gran;
 1617 }
 1618 
 1619 /*
 1620  * Populate the (physmap) array with base/bound pairs describing the
 1621  * available physical memory in the system, then test this memory and
 1622  * build the phys_avail array describing the actually-available memory.
 1623  *
 1624  * If we cannot accurately determine the physical memory map, then use
 1625  * value from the 0xE801 call, and failing that, the RTC.
 1626  *
 1627  * Total memory size may be set by the kernel environment variable
 1628  * hw.physmem or the compile-time define MAXMEM.
 1629  *
 1630  * XXX first should be vm_paddr_t.
 1631  */
 1632 static void
 1633 getmemsize(int first)
 1634 {
 1635         int i, off, physmap_idx, pa_indx, da_indx;
 1636         int pg_n;
 1637         u_long physmem_tunable;
 1638         u_int extmem, under16;
 1639         vm_paddr_t pa, physmap[PHYSMAP_SIZE];
 1640         pt_entry_t *pte;
 1641         quad_t dcons_addr, dcons_size;
 1642 
 1643         bzero(physmap, sizeof(physmap));
 1644 
 1645         /* XXX - some of EPSON machines can't use PG_N */
 1646         pg_n = PG_N;
 1647         if (pc98_machine_type & M_EPSON_PC98) {
 1648                 switch (epson_machine_id) {
 1649 #ifdef WB_CACHE
 1650                 default:
 1651 #endif
 1652                 case EPSON_PC486_HX:
 1653                 case EPSON_PC486_HG:
 1654                 case EPSON_PC486_HA:
 1655                         pg_n = 0;
 1656                         break;
 1657                 }
 1658         }
 1659 
 1660         /*
 1661          * Perform "base memory" related probes & setup
 1662          */
 1663         under16 = pc98_getmemsize(&basemem, &extmem);
 1664         if (basemem > 640) {
 1665                 printf("Preposterous BIOS basemem of %uK, truncating to 640K\n",
 1666                         basemem);
 1667                 basemem = 640;
 1668         }
 1669 
 1670         /*
 1671          * XXX if biosbasemem is now < 640, there is a `hole'
 1672          * between the end of base memory and the start of
 1673          * ISA memory.  The hole may be empty or it may
 1674          * contain BIOS code or data.  Map it read/write so
 1675          * that the BIOS can write to it.  (Memory from 0 to
 1676          * the physical end of the kernel is mapped read-only
 1677          * to begin with and then parts of it are remapped.
 1678          * The parts that aren't remapped form holes that
 1679          * remain read-only and are unused by the kernel.
 1680          * The base memory area is below the physical end of
 1681          * the kernel and right now forms a read-only hole.
 1682          * The part of it from PAGE_SIZE to
 1683          * (trunc_page(biosbasemem * 1024) - 1) will be
 1684          * remapped and used by the kernel later.)
 1685          *
 1686          * This code is similar to the code used in
 1687          * pmap_mapdev, but since no memory needs to be
 1688          * allocated we simply change the mapping.
 1689          */
 1690         for (pa = trunc_page(basemem * 1024);
 1691              pa < ISA_HOLE_START; pa += PAGE_SIZE)
 1692                 pmap_kenter(KERNBASE + pa, pa);
 1693 
 1694         /*
 1695          * if basemem != 640, map pages r/w into vm86 page table so 
 1696          * that the bios can scribble on it.
 1697          */
 1698         pte = (pt_entry_t *)vm86paddr;
 1699         for (i = basemem / 4; i < 160; i++)
 1700                 pte[i] = (i << PAGE_SHIFT) | PG_V | PG_RW | PG_U;
 1701 
 1702         physmap[0] = 0;
 1703         physmap[1] = basemem * 1024;
 1704         physmap_idx = 2;
 1705         physmap[physmap_idx] = 0x100000;
 1706         physmap[physmap_idx + 1] = physmap[physmap_idx] + extmem * 1024;
 1707 
 1708         /*
 1709          * Now, physmap contains a map of physical memory.
 1710          */
 1711 
 1712 #ifdef SMP
 1713         /* make hole for AP bootstrap code */
 1714         physmap[1] = mp_bootaddress(physmap[1]);
 1715 #endif
 1716 
 1717         /*
 1718          * Maxmem isn't the "maximum memory", it's one larger than the
 1719          * highest page of the physical address space.  It should be
 1720          * called something like "Maxphyspage".  We may adjust this 
 1721          * based on ``hw.physmem'' and the results of the memory test.
 1722          */
 1723         Maxmem = atop(physmap[physmap_idx + 1]);
 1724 
 1725 #ifdef MAXMEM
 1726         Maxmem = MAXMEM / 4;
 1727 #endif
 1728 
 1729         if (TUNABLE_ULONG_FETCH("hw.physmem", &physmem_tunable))
 1730                 Maxmem = atop(physmem_tunable);
 1731 
 1732         if (atop(physmap[physmap_idx + 1]) != Maxmem &&
 1733             (boothowto & RB_VERBOSE))
 1734                 printf("Physical memory use set to %ldK\n", Maxmem * 4);
 1735 
 1736         /*
 1737          * If Maxmem has been increased beyond what the system has detected,
 1738          * extend the last memory segment to the new limit.
 1739          */ 
 1740         if (atop(physmap[physmap_idx + 1]) < Maxmem)
 1741                 physmap[physmap_idx + 1] = ptoa((vm_paddr_t)Maxmem);
 1742 
 1743         /*
 1744          * We need to divide chunk if Maxmem is larger than 16MB and
 1745          * under 16MB area is not full of memory.
 1746          * (1) system area (15-16MB region) is cut off
 1747          * (2) extended memory is only over 16MB area (ex. Melco "HYPERMEMORY")
 1748          */
 1749         if ((under16 != 16 * 1024) && (extmem > 15 * 1024)) {
 1750                 /* 15M - 16M region is cut off, so need to divide chunk */
 1751                 physmap[physmap_idx + 1] = under16 * 1024;
 1752                 physmap_idx += 2;
 1753                 physmap[physmap_idx] = 0x1000000;
 1754                 physmap[physmap_idx + 1] = physmap[2] + extmem * 1024;
 1755         }
 1756 
 1757         /* call pmap initialization to make new kernel address space */
 1758         pmap_bootstrap(first);
 1759 
 1760         /*
 1761          * Size up each available chunk of physical memory.
 1762          */
 1763         physmap[0] = PAGE_SIZE;         /* mask off page 0 */
 1764         pa_indx = 0;
 1765         da_indx = 1;
 1766         phys_avail[pa_indx++] = physmap[0];
 1767         phys_avail[pa_indx] = physmap[0];
 1768         dump_avail[da_indx] = physmap[0];
 1769         pte = CMAP1;
 1770 
 1771         /*
 1772          * Get dcons buffer address
 1773          */
 1774         if (getenv_quad("dcons.addr", &dcons_addr) == 0 ||
 1775             getenv_quad("dcons.size", &dcons_size) == 0)
 1776                 dcons_addr = 0;
 1777 
 1778         /*
 1779          * physmap is in bytes, so when converting to page boundaries,
 1780          * round up the start address and round down the end address.
 1781          */
 1782         for (i = 0; i <= physmap_idx; i += 2) {
 1783                 vm_paddr_t end;
 1784 
 1785                 end = ptoa((vm_paddr_t)Maxmem);
 1786                 if (physmap[i + 1] < end)
 1787                         end = trunc_page(physmap[i + 1]);
 1788                 for (pa = round_page(physmap[i]); pa < end; pa += PAGE_SIZE) {
 1789                         int tmp, page_bad, full;
 1790                         int *ptr = (int *)CADDR1;
 1791 
 1792                         full = FALSE;
 1793                         /*
 1794                          * block out kernel memory as not available.
 1795                          */
 1796                         if (pa >= KERNLOAD && pa < first)
 1797                                 goto do_dump_avail;
 1798 
 1799                         /*
 1800                          * block out dcons buffer
 1801                          */
 1802                         if (dcons_addr > 0
 1803                             && pa >= trunc_page(dcons_addr)
 1804                             && pa < dcons_addr + dcons_size)
 1805                                 goto do_dump_avail;
 1806 
 1807                         page_bad = FALSE;
 1808 
 1809                         /*
 1810                          * map page into kernel: valid, read/write,non-cacheable
 1811                          */
 1812                         *pte = pa | PG_V | PG_RW | pg_n;
 1813                         invltlb();
 1814 
 1815                         tmp = *(int *)ptr;
 1816                         /*
 1817                          * Test for alternating 1's and 0's
 1818                          */
 1819                         *(volatile int *)ptr = 0xaaaaaaaa;
 1820                         if (*(volatile int *)ptr != 0xaaaaaaaa)
 1821                                 page_bad = TRUE;
 1822                         /*
 1823                          * Test for alternating 0's and 1's
 1824                          */
 1825                         *(volatile int *)ptr = 0x55555555;
 1826                         if (*(volatile int *)ptr != 0x55555555)
 1827                                 page_bad = TRUE;
 1828                         /*
 1829                          * Test for all 1's
 1830                          */
 1831                         *(volatile int *)ptr = 0xffffffff;
 1832                         if (*(volatile int *)ptr != 0xffffffff)
 1833                                 page_bad = TRUE;
 1834                         /*
 1835                          * Test for all 0's
 1836                          */
 1837                         *(volatile int *)ptr = 0x0;
 1838                         if (*(volatile int *)ptr != 0x0)
 1839                                 page_bad = TRUE;
 1840                         /*
 1841                          * Restore original value.
 1842                          */
 1843                         *(int *)ptr = tmp;
 1844 
 1845                         /*
 1846                          * Adjust array of valid/good pages.
 1847                          */
 1848                         if (page_bad == TRUE)
 1849                                 continue;
 1850                         /*
 1851                          * If this good page is a continuation of the
 1852                          * previous set of good pages, then just increase
 1853                          * the end pointer. Otherwise start a new chunk.
 1854                          * Note that "end" points one higher than end,
 1855                          * making the range >= start and < end.
 1856                          * If we're also doing a speculative memory
 1857                          * test and we at or past the end, bump up Maxmem
 1858                          * so that we keep going. The first bad page
 1859                          * will terminate the loop.
 1860                          */
 1861                         if (phys_avail[pa_indx] == pa) {
 1862                                 phys_avail[pa_indx] += PAGE_SIZE;
 1863                         } else {
 1864                                 pa_indx++;
 1865                                 if (pa_indx == PHYS_AVAIL_ARRAY_END) {
 1866                                         printf(
 1867                 "Too many holes in the physical address space, giving up\n");
 1868                                         pa_indx--;
 1869                                         full = TRUE;
 1870                                         goto do_dump_avail;
 1871                                 }
 1872                                 phys_avail[pa_indx++] = pa;     /* start */
 1873                                 phys_avail[pa_indx] = pa + PAGE_SIZE; /* end */
 1874                         }
 1875                         physmem++;
 1876 do_dump_avail:
 1877                         if (dump_avail[da_indx] == pa) {
 1878                                 dump_avail[da_indx] += PAGE_SIZE;
 1879                         } else {
 1880                                 da_indx++;
 1881                                 if (da_indx == DUMP_AVAIL_ARRAY_END) {
 1882                                         da_indx--;
 1883                                         goto do_next;
 1884                                 }
 1885                                 dump_avail[da_indx++] = pa;     /* start */
 1886                                 dump_avail[da_indx] = pa + PAGE_SIZE; /* end */
 1887                         }
 1888 do_next:
 1889                         if (full)
 1890                                 break;
 1891                 }
 1892         }
 1893         *pte = 0;
 1894         invltlb();
 1895 
 1896         /*
 1897          * XXX
 1898          * The last chunk must contain at least one page plus the message
 1899          * buffer to avoid complicating other code (message buffer address
 1900          * calculation, etc.).
 1901          */
 1902         while (phys_avail[pa_indx - 1] + PAGE_SIZE +
 1903             round_page(MSGBUF_SIZE) >= phys_avail[pa_indx]) {
 1904                 physmem -= atop(phys_avail[pa_indx] - phys_avail[pa_indx - 1]);
 1905                 phys_avail[pa_indx--] = 0;
 1906                 phys_avail[pa_indx--] = 0;
 1907         }
 1908 
 1909         Maxmem = atop(phys_avail[pa_indx]);
 1910 
 1911         /* Trim off space for the message buffer. */
 1912         phys_avail[pa_indx] -= round_page(MSGBUF_SIZE);
 1913 
 1914         /* Map the message buffer. */
 1915         for (off = 0; off < round_page(MSGBUF_SIZE); off += PAGE_SIZE)
 1916                 pmap_kenter((vm_offset_t)msgbufp + off, phys_avail[pa_indx] +
 1917                     off);
 1918 }
 1919 
 1920 void
 1921 init386(first)
 1922         int first;
 1923 {
 1924         struct gate_descriptor *gdp;
 1925         int gsel_tss, metadata_missing, x;
 1926         struct pcpu *pc;
 1927 
 1928         thread0.td_kstack = proc0kstack;
 1929         thread0.td_pcb = (struct pcb *)
 1930            (thread0.td_kstack + KSTACK_PAGES * PAGE_SIZE) - 1;
 1931 
 1932         /*
 1933          * This may be done better later if it gets more high level
 1934          * components in it. If so just link td->td_proc here.
 1935          */
 1936         proc_linkup0(&proc0, &thread0);
 1937 
 1938         /*
 1939          * Initialize DMAC
 1940          */
 1941         pc98_init_dmac();
 1942 
 1943         metadata_missing = 0;
 1944         if (bootinfo.bi_modulep) {
 1945                 preload_metadata = (caddr_t)bootinfo.bi_modulep + KERNBASE;
 1946                 preload_bootstrap_relocate(KERNBASE);
 1947         } else {
 1948                 metadata_missing = 1;
 1949         }
 1950         if (envmode == 1)
 1951                 kern_envp = static_env;
 1952         else if (bootinfo.bi_envp)
 1953                 kern_envp = (caddr_t)bootinfo.bi_envp + KERNBASE;
 1954 
 1955         /* Init basic tunables, hz etc */
 1956         init_param1();
 1957 
 1958         /*
 1959          * Make gdt memory segments.  All segments cover the full 4GB
 1960          * of address space and permissions are enforced at page level.
 1961          */
 1962         gdt_segs[GCODE_SEL].ssd_limit = atop(0 - 1);
 1963         gdt_segs[GDATA_SEL].ssd_limit = atop(0 - 1);
 1964         gdt_segs[GUCODE_SEL].ssd_limit = atop(0 - 1);
 1965         gdt_segs[GUDATA_SEL].ssd_limit = atop(0 - 1);
 1966         gdt_segs[GUFS_SEL].ssd_limit = atop(0 - 1);
 1967         gdt_segs[GUGS_SEL].ssd_limit = atop(0 - 1);
 1968 
 1969         pc = &__pcpu[0];
 1970         gdt_segs[GPRIV_SEL].ssd_limit = atop(0 - 1);
 1971         gdt_segs[GPRIV_SEL].ssd_base = (int) pc;
 1972         gdt_segs[GPROC0_SEL].ssd_base = (int) &pc->pc_common_tss;
 1973 
 1974         for (x = 0; x < NGDT; x++)
 1975                 ssdtosd(&gdt_segs[x], &gdt[x].sd);
 1976 
 1977         r_gdt.rd_limit = NGDT * sizeof(gdt[0]) - 1;
 1978         r_gdt.rd_base =  (int) gdt;
 1979         mtx_init(&dt_lock, "descriptor tables", NULL, MTX_SPIN);
 1980         lgdt(&r_gdt);
 1981 
 1982         pcpu_init(pc, 0, sizeof(struct pcpu));
 1983         PCPU_SET(prvspace, pc);
 1984         PCPU_SET(curthread, &thread0);
 1985         PCPU_SET(curpcb, thread0.td_pcb);
 1986 
 1987         /*
 1988          * Initialize mutexes.
 1989          *
 1990          * icu_lock: in order to allow an interrupt to occur in a critical
 1991          *           section, to set pcpu->ipending (etc...) properly, we
 1992          *           must be able to get the icu lock, so it can't be
 1993          *           under witness.
 1994          */
 1995         mutex_init();
 1996         mtx_init(&icu_lock, "icu", NULL, MTX_SPIN | MTX_NOWITNESS | MTX_NOPROFILE);
 1997 
 1998         /* make ldt memory segments */
 1999         ldt_segs[LUCODE_SEL].ssd_limit = atop(0 - 1);
 2000         ldt_segs[LUDATA_SEL].ssd_limit = atop(0 - 1);
 2001         for (x = 0; x < sizeof ldt_segs / sizeof ldt_segs[0]; x++)
 2002                 ssdtosd(&ldt_segs[x], &ldt[x].sd);
 2003 
 2004         _default_ldt = GSEL(GLDT_SEL, SEL_KPL);
 2005         lldt(_default_ldt);
 2006         PCPU_SET(currentldt, _default_ldt);
 2007 
 2008         /* exceptions */
 2009         for (x = 0; x < NIDT; x++)
 2010                 setidt(x, &IDTVEC(rsvd), SDT_SYS386TGT, SEL_KPL,
 2011                     GSEL(GCODE_SEL, SEL_KPL));
 2012         setidt(IDT_DE, &IDTVEC(div),  SDT_SYS386TGT, SEL_KPL,
 2013             GSEL(GCODE_SEL, SEL_KPL));
 2014         setidt(IDT_DB, &IDTVEC(dbg),  SDT_SYS386IGT, SEL_KPL,
 2015             GSEL(GCODE_SEL, SEL_KPL));
 2016         setidt(IDT_NMI, &IDTVEC(nmi),  SDT_SYS386IGT, SEL_KPL,
 2017             GSEL(GCODE_SEL, SEL_KPL));
 2018         setidt(IDT_BP, &IDTVEC(bpt),  SDT_SYS386IGT, SEL_UPL,
 2019             GSEL(GCODE_SEL, SEL_KPL));
 2020         setidt(IDT_OF, &IDTVEC(ofl),  SDT_SYS386TGT, SEL_UPL,
 2021             GSEL(GCODE_SEL, SEL_KPL));
 2022         setidt(IDT_BR, &IDTVEC(bnd),  SDT_SYS386TGT, SEL_KPL,
 2023             GSEL(GCODE_SEL, SEL_KPL));
 2024         setidt(IDT_UD, &IDTVEC(ill),  SDT_SYS386TGT, SEL_KPL,
 2025             GSEL(GCODE_SEL, SEL_KPL));
 2026         setidt(IDT_NM, &IDTVEC(dna),  SDT_SYS386TGT, SEL_KPL
 2027             , GSEL(GCODE_SEL, SEL_KPL));
 2028         setidt(IDT_DF, 0,  SDT_SYSTASKGT, SEL_KPL, GSEL(GPANIC_SEL, SEL_KPL));
 2029         setidt(IDT_FPUGP, &IDTVEC(fpusegm),  SDT_SYS386TGT, SEL_KPL,
 2030             GSEL(GCODE_SEL, SEL_KPL));
 2031         setidt(IDT_TS, &IDTVEC(tss),  SDT_SYS386TGT, SEL_KPL,
 2032             GSEL(GCODE_SEL, SEL_KPL));
 2033         setidt(IDT_NP, &IDTVEC(missing),  SDT_SYS386TGT, SEL_KPL,
 2034             GSEL(GCODE_SEL, SEL_KPL));
 2035         setidt(IDT_SS, &IDTVEC(stk),  SDT_SYS386TGT, SEL_KPL,
 2036             GSEL(GCODE_SEL, SEL_KPL));
 2037         setidt(IDT_GP, &IDTVEC(prot),  SDT_SYS386TGT, SEL_KPL,
 2038             GSEL(GCODE_SEL, SEL_KPL));
 2039         setidt(IDT_PF, &IDTVEC(page),  SDT_SYS386IGT, SEL_KPL,
 2040             GSEL(GCODE_SEL, SEL_KPL));
 2041         setidt(IDT_MF, &IDTVEC(fpu),  SDT_SYS386TGT, SEL_KPL,
 2042             GSEL(GCODE_SEL, SEL_KPL));
 2043         setidt(IDT_AC, &IDTVEC(align), SDT_SYS386TGT, SEL_KPL,
 2044             GSEL(GCODE_SEL, SEL_KPL));
 2045         setidt(IDT_MC, &IDTVEC(mchk),  SDT_SYS386TGT, SEL_KPL,
 2046             GSEL(GCODE_SEL, SEL_KPL));
 2047         setidt(IDT_XF, &IDTVEC(xmm), SDT_SYS386TGT, SEL_KPL,
 2048             GSEL(GCODE_SEL, SEL_KPL));
 2049         setidt(IDT_SYSCALL, &IDTVEC(int0x80_syscall), SDT_SYS386TGT, SEL_UPL,
 2050             GSEL(GCODE_SEL, SEL_KPL));
 2051 
 2052         r_idt.rd_limit = sizeof(idt0) - 1;
 2053         r_idt.rd_base = (int) idt;
 2054         lidt(&r_idt);
 2055 
 2056         /*
 2057          * Initialize the i8254 before the console so that console
 2058          * initialization can use DELAY().
 2059          */
 2060         i8254_init();
 2061 
 2062         /*
 2063          * Initialize the console before we print anything out.
 2064          */
 2065         cninit();
 2066 
 2067         if (metadata_missing)
 2068                 printf("WARNING: loader(8) metadata is missing!\n");
 2069 
 2070 #ifdef DEV_ISA
 2071         atpic_startup();
 2072 #endif
 2073 
 2074 #ifdef DDB
 2075         ksym_start = bootinfo.bi_symtab;
 2076         ksym_end = bootinfo.bi_esymtab;
 2077 #endif
 2078 
 2079         kdb_init();
 2080 
 2081 #ifdef KDB
 2082         if (boothowto & RB_KDB)
 2083                 kdb_enter_why(KDB_WHY_BOOTFLAGS,
 2084                     "Boot flags requested debugger");
 2085 #endif
 2086 
 2087         finishidentcpu();       /* Final stage of CPU initialization */
 2088         setidt(IDT_UD, &IDTVEC(ill),  SDT_SYS386TGT, SEL_KPL,
 2089             GSEL(GCODE_SEL, SEL_KPL));
 2090         setidt(IDT_GP, &IDTVEC(prot),  SDT_SYS386TGT, SEL_KPL,
 2091             GSEL(GCODE_SEL, SEL_KPL));
 2092         initializecpu();        /* Initialize CPU registers */
 2093 
 2094         /* make an initial tss so cpu can get interrupt stack on syscall! */
 2095         /* Note: -16 is so we can grow the trapframe if we came from vm86 */
 2096         PCPU_SET(common_tss.tss_esp0, thread0.td_kstack +
 2097             KSTACK_PAGES * PAGE_SIZE - sizeof(struct pcb) - 16);
 2098         PCPU_SET(common_tss.tss_ss0, GSEL(GDATA_SEL, SEL_KPL));
 2099         gsel_tss = GSEL(GPROC0_SEL, SEL_KPL);
 2100         PCPU_SET(tss_gdt, &gdt[GPROC0_SEL].sd);
 2101         PCPU_SET(common_tssd, *PCPU_GET(tss_gdt));
 2102         PCPU_SET(common_tss.tss_ioopt, (sizeof (struct i386tss)) << 16);
 2103         ltr(gsel_tss);
 2104 
 2105         /* pointer to selector slot for %fs/%gs */
 2106         PCPU_SET(fsgs_gdt, &gdt[GUFS_SEL].sd);
 2107 
 2108         dblfault_tss.tss_esp = dblfault_tss.tss_esp0 = dblfault_tss.tss_esp1 =
 2109             dblfault_tss.tss_esp2 = (int)&dblfault_stack[sizeof(dblfault_stack)];
 2110         dblfault_tss.tss_ss = dblfault_tss.tss_ss0 = dblfault_tss.tss_ss1 =
 2111             dblfault_tss.tss_ss2 = GSEL(GDATA_SEL, SEL_KPL);
 2112         dblfault_tss.tss_cr3 = (int)IdlePTD;
 2113         dblfault_tss.tss_eip = (int)dblfault_handler;
 2114         dblfault_tss.tss_eflags = PSL_KERNEL;
 2115         dblfault_tss.tss_ds = dblfault_tss.tss_es =
 2116             dblfault_tss.tss_gs = GSEL(GDATA_SEL, SEL_KPL);
 2117         dblfault_tss.tss_fs = GSEL(GPRIV_SEL, SEL_KPL);
 2118         dblfault_tss.tss_cs = GSEL(GCODE_SEL, SEL_KPL);
 2119         dblfault_tss.tss_ldt = GSEL(GLDT_SEL, SEL_KPL);
 2120 
 2121         vm86_initialize();
 2122         getmemsize(first);
 2123         init_param2(physmem);
 2124 
 2125         /* now running on new page tables, configured,and u/iom is accessible */
 2126 
 2127         msgbufinit(msgbufp, MSGBUF_SIZE);
 2128 
 2129         /* make a call gate to reenter kernel with */
 2130         gdp = &ldt[LSYS5CALLS_SEL].gd;
 2131 
 2132         x = (int) &IDTVEC(lcall_syscall);
 2133         gdp->gd_looffset = x;
 2134         gdp->gd_selector = GSEL(GCODE_SEL,SEL_KPL);
 2135         gdp->gd_stkcpy = 1;
 2136         gdp->gd_type = SDT_SYS386CGT;
 2137         gdp->gd_dpl = SEL_UPL;
 2138         gdp->gd_p = 1;
 2139         gdp->gd_hioffset = x >> 16;
 2140 
 2141         /* XXX does this work? */
 2142         /* XXX yes! */
 2143         ldt[LBSDICALLS_SEL] = ldt[LSYS5CALLS_SEL];
 2144         ldt[LSOL26CALLS_SEL] = ldt[LSYS5CALLS_SEL];
 2145 
 2146         /* transfer to user mode */
 2147 
 2148         _ucodesel = GSEL(GUCODE_SEL, SEL_UPL);
 2149         _udatasel = GSEL(GUDATA_SEL, SEL_UPL);
 2150 
 2151         /* setup proc 0's pcb */
 2152         thread0.td_pcb->pcb_flags = 0; /* XXXKSE */
 2153         thread0.td_pcb->pcb_cr3 = (int)IdlePTD;
 2154         thread0.td_pcb->pcb_ext = 0;
 2155         thread0.td_frame = &proc0_tf;
 2156 }
 2157 
 2158 void
 2159 cpu_pcpu_init(struct pcpu *pcpu, int cpuid, size_t size)
 2160 {
 2161 
 2162 }
 2163 
 2164 void
 2165 spinlock_enter(void)
 2166 {
 2167         struct thread *td;
 2168 
 2169         td = curthread;
 2170         if (td->td_md.md_spinlock_count == 0)
 2171                 td->td_md.md_saved_flags = intr_disable();
 2172         td->td_md.md_spinlock_count++;
 2173         critical_enter();
 2174 }
 2175 
 2176 void
 2177 spinlock_exit(void)
 2178 {
 2179         struct thread *td;
 2180 
 2181         td = curthread;
 2182         critical_exit();
 2183         td->td_md.md_spinlock_count--;
 2184         if (td->td_md.md_spinlock_count == 0)
 2185                 intr_restore(td->td_md.md_saved_flags);
 2186 }
 2187 
 2188 #if defined(I586_CPU) && !defined(NO_F00F_HACK)
 2189 static void f00f_hack(void *unused);
 2190 SYSINIT(f00f_hack, SI_SUB_INTRINSIC, SI_ORDER_FIRST, f00f_hack, NULL);
 2191 
 2192 static void
 2193 f00f_hack(void *unused)
 2194 {
 2195         struct gate_descriptor *new_idt;
 2196         vm_offset_t tmp;
 2197 
 2198         if (!has_f00f_bug)
 2199                 return;
 2200 
 2201         GIANT_REQUIRED;
 2202 
 2203         printf("Intel Pentium detected, installing workaround for F00F bug\n");
 2204 
 2205         tmp = kmem_alloc(kernel_map, PAGE_SIZE * 2);
 2206         if (tmp == 0)
 2207                 panic("kmem_alloc returned 0");
 2208 
 2209         /* Put the problematic entry (#6) at the end of the lower page. */
 2210         new_idt = (struct gate_descriptor*)
 2211             (tmp + PAGE_SIZE - 7 * sizeof(struct gate_descriptor));
 2212         bcopy(idt, new_idt, sizeof(idt0));
 2213         r_idt.rd_base = (u_int)new_idt;
 2214         lidt(&r_idt);
 2215         idt = new_idt;
 2216         if (vm_map_protect(kernel_map, tmp, tmp + PAGE_SIZE,
 2217                            VM_PROT_READ, FALSE) != KERN_SUCCESS)
 2218                 panic("vm_map_protect failed");
 2219 }
 2220 #endif /* defined(I586_CPU) && !NO_F00F_HACK */
 2221 
 2222 /*
 2223  * Construct a PCB from a trapframe. This is called from kdb_trap() where
 2224  * we want to start a backtrace from the function that caused us to enter
 2225  * the debugger. We have the context in the trapframe, but base the trace
 2226  * on the PCB. The PCB doesn't have to be perfect, as long as it contains
 2227  * enough for a backtrace.
 2228  */
 2229 void
 2230 makectx(struct trapframe *tf, struct pcb *pcb)
 2231 {
 2232 
 2233         pcb->pcb_edi = tf->tf_edi;
 2234         pcb->pcb_esi = tf->tf_esi;
 2235         pcb->pcb_ebp = tf->tf_ebp;
 2236         pcb->pcb_ebx = tf->tf_ebx;
 2237         pcb->pcb_eip = tf->tf_eip;
 2238         pcb->pcb_esp = (ISPL(tf->tf_cs)) ? tf->tf_esp : (int)(tf + 1) - 8;
 2239 }
 2240 
 2241 int
 2242 ptrace_set_pc(struct thread *td, u_long addr)
 2243 {
 2244 
 2245         td->td_frame->tf_eip = addr;
 2246         return (0);
 2247 }
 2248 
 2249 int
 2250 ptrace_single_step(struct thread *td)
 2251 {
 2252         td->td_frame->tf_eflags |= PSL_T;
 2253         return (0);
 2254 }
 2255 
 2256 int
 2257 ptrace_clear_single_step(struct thread *td)
 2258 {
 2259         td->td_frame->tf_eflags &= ~PSL_T;
 2260         return (0);
 2261 }
 2262 
 2263 int
 2264 fill_regs(struct thread *td, struct reg *regs)
 2265 {
 2266         struct pcb *pcb;
 2267         struct trapframe *tp;
 2268 
 2269         tp = td->td_frame;
 2270         pcb = td->td_pcb;
 2271         regs->r_fs = tp->tf_fs;
 2272         regs->r_es = tp->tf_es;
 2273         regs->r_ds = tp->tf_ds;
 2274         regs->r_edi = tp->tf_edi;
 2275         regs->r_esi = tp->tf_esi;
 2276         regs->r_ebp = tp->tf_ebp;
 2277         regs->r_ebx = tp->tf_ebx;
 2278         regs->r_edx = tp->tf_edx;
 2279         regs->r_ecx = tp->tf_ecx;
 2280         regs->r_eax = tp->tf_eax;
 2281         regs->r_eip = tp->tf_eip;
 2282         regs->r_cs = tp->tf_cs;
 2283         regs->r_eflags = tp->tf_eflags;
 2284         regs->r_esp = tp->tf_esp;
 2285         regs->r_ss = tp->tf_ss;
 2286         regs->r_gs = pcb->pcb_gs;
 2287         return (0);
 2288 }
 2289 
 2290 int
 2291 set_regs(struct thread *td, struct reg *regs)
 2292 {
 2293         struct pcb *pcb;
 2294         struct trapframe *tp;
 2295 
 2296         tp = td->td_frame;
 2297         if (!EFL_SECURE(regs->r_eflags, tp->tf_eflags) ||
 2298             !CS_SECURE(regs->r_cs))
 2299                 return (EINVAL);
 2300         pcb = td->td_pcb;
 2301         tp->tf_fs = regs->r_fs;
 2302         tp->tf_es = regs->r_es;
 2303         tp->tf_ds = regs->r_ds;
 2304         tp->tf_edi = regs->r_edi;
 2305         tp->tf_esi = regs->r_esi;
 2306         tp->tf_ebp = regs->r_ebp;
 2307         tp->tf_ebx = regs->r_ebx;
 2308         tp->tf_edx = regs->r_edx;
 2309         tp->tf_ecx = regs->r_ecx;
 2310         tp->tf_eax = regs->r_eax;
 2311         tp->tf_eip = regs->r_eip;
 2312         tp->tf_cs = regs->r_cs;
 2313         tp->tf_eflags = regs->r_eflags;
 2314         tp->tf_esp = regs->r_esp;
 2315         tp->tf_ss = regs->r_ss;
 2316         pcb->pcb_gs = regs->r_gs;
 2317         return (0);
 2318 }
 2319 
 2320 #ifdef CPU_ENABLE_SSE
 2321 static void
 2322 fill_fpregs_xmm(sv_xmm, sv_87)
 2323         struct savexmm *sv_xmm;
 2324         struct save87 *sv_87;
 2325 {
 2326         register struct env87 *penv_87 = &sv_87->sv_env;
 2327         register struct envxmm *penv_xmm = &sv_xmm->sv_env;
 2328         int i;
 2329 
 2330         bzero(sv_87, sizeof(*sv_87));
 2331 
 2332         /* FPU control/status */
 2333         penv_87->en_cw = penv_xmm->en_cw;
 2334         penv_87->en_sw = penv_xmm->en_sw;
 2335         penv_87->en_tw = penv_xmm->en_tw;
 2336         penv_87->en_fip = penv_xmm->en_fip;
 2337         penv_87->en_fcs = penv_xmm->en_fcs;
 2338         penv_87->en_opcode = penv_xmm->en_opcode;
 2339         penv_87->en_foo = penv_xmm->en_foo;
 2340         penv_87->en_fos = penv_xmm->en_fos;
 2341 
 2342         /* FPU registers */
 2343         for (i = 0; i < 8; ++i)
 2344                 sv_87->sv_ac[i] = sv_xmm->sv_fp[i].fp_acc;
 2345 }
 2346 
 2347 static void
 2348 set_fpregs_xmm(sv_87, sv_xmm)
 2349         struct save87 *sv_87;
 2350         struct savexmm *sv_xmm;
 2351 {
 2352         register struct env87 *penv_87 = &sv_87->sv_env;
 2353         register struct envxmm *penv_xmm = &sv_xmm->sv_env;
 2354         int i;
 2355 
 2356         /* FPU control/status */
 2357         penv_xmm->en_cw = penv_87->en_cw;
 2358         penv_xmm->en_sw = penv_87->en_sw;
 2359         penv_xmm->en_tw = penv_87->en_tw;
 2360         penv_xmm->en_fip = penv_87->en_fip;
 2361         penv_xmm->en_fcs = penv_87->en_fcs;
 2362         penv_xmm->en_opcode = penv_87->en_opcode;
 2363         penv_xmm->en_foo = penv_87->en_foo;
 2364         penv_xmm->en_fos = penv_87->en_fos;
 2365 
 2366         /* FPU registers */
 2367         for (i = 0; i < 8; ++i)
 2368                 sv_xmm->sv_fp[i].fp_acc = sv_87->sv_ac[i];
 2369 }
 2370 #endif /* CPU_ENABLE_SSE */
 2371 
 2372 int
 2373 fill_fpregs(struct thread *td, struct fpreg *fpregs)
 2374 {
 2375 #ifdef CPU_ENABLE_SSE
 2376         if (cpu_fxsr) {
 2377                 fill_fpregs_xmm(&td->td_pcb->pcb_save.sv_xmm,
 2378                                                 (struct save87 *)fpregs);
 2379                 return (0);
 2380         }
 2381 #endif /* CPU_ENABLE_SSE */
 2382         bcopy(&td->td_pcb->pcb_save.sv_87, fpregs, sizeof *fpregs);
 2383         return (0);
 2384 }
 2385 
 2386 int
 2387 set_fpregs(struct thread *td, struct fpreg *fpregs)
 2388 {
 2389 #ifdef CPU_ENABLE_SSE
 2390         if (cpu_fxsr) {
 2391                 set_fpregs_xmm((struct save87 *)fpregs,
 2392                                            &td->td_pcb->pcb_save.sv_xmm);
 2393                 return (0);
 2394         }
 2395 #endif /* CPU_ENABLE_SSE */
 2396         bcopy(fpregs, &td->td_pcb->pcb_save.sv_87, sizeof *fpregs);
 2397         return (0);
 2398 }
 2399 
 2400 /*
 2401  * Get machine context.
 2402  */
 2403 int
 2404 get_mcontext(struct thread *td, mcontext_t *mcp, int flags)
 2405 {
 2406         struct trapframe *tp;
 2407 
 2408         tp = td->td_frame;
 2409 
 2410         PROC_LOCK(curthread->td_proc);
 2411         mcp->mc_onstack = sigonstack(tp->tf_esp);
 2412         PROC_UNLOCK(curthread->td_proc);
 2413         mcp->mc_gs = td->td_pcb->pcb_gs;
 2414         mcp->mc_fs = tp->tf_fs;
 2415         mcp->mc_es = tp->tf_es;
 2416         mcp->mc_ds = tp->tf_ds;
 2417         mcp->mc_edi = tp->tf_edi;
 2418         mcp->mc_esi = tp->tf_esi;
 2419         mcp->mc_ebp = tp->tf_ebp;
 2420         mcp->mc_isp = tp->tf_isp;
 2421         mcp->mc_eflags = tp->tf_eflags;
 2422         if (flags & GET_MC_CLEAR_RET) {
 2423                 mcp->mc_eax = 0;
 2424                 mcp->mc_edx = 0;
 2425                 mcp->mc_eflags &= ~PSL_C;
 2426         } else {
 2427                 mcp->mc_eax = tp->tf_eax;
 2428                 mcp->mc_edx = tp->tf_edx;
 2429         }
 2430         mcp->mc_ebx = tp->tf_ebx;
 2431         mcp->mc_ecx = tp->tf_ecx;
 2432         mcp->mc_eip = tp->tf_eip;
 2433         mcp->mc_cs = tp->tf_cs;
 2434         mcp->mc_esp = tp->tf_esp;
 2435         mcp->mc_ss = tp->tf_ss;
 2436         mcp->mc_len = sizeof(*mcp);
 2437         get_fpcontext(td, mcp);
 2438         return (0);
 2439 }
 2440 
 2441 /*
 2442  * Set machine context.
 2443  *
 2444  * However, we don't set any but the user modifiable flags, and we won't
 2445  * touch the cs selector.
 2446  */
 2447 int
 2448 set_mcontext(struct thread *td, const mcontext_t *mcp)
 2449 {
 2450         struct trapframe *tp;
 2451         int eflags, ret;
 2452 
 2453         tp = td->td_frame;
 2454         if (mcp->mc_len != sizeof(*mcp))
 2455                 return (EINVAL);
 2456         eflags = (mcp->mc_eflags & PSL_USERCHANGE) |
 2457             (tp->tf_eflags & ~PSL_USERCHANGE);
 2458         if ((ret = set_fpcontext(td, mcp)) == 0) {
 2459                 tp->tf_fs = mcp->mc_fs;
 2460                 tp->tf_es = mcp->mc_es;
 2461                 tp->tf_ds = mcp->mc_ds;
 2462                 tp->tf_edi = mcp->mc_edi;
 2463                 tp->tf_esi = mcp->mc_esi;
 2464                 tp->tf_ebp = mcp->mc_ebp;
 2465                 tp->tf_ebx = mcp->mc_ebx;
 2466                 tp->tf_edx = mcp->mc_edx;
 2467                 tp->tf_ecx = mcp->mc_ecx;
 2468                 tp->tf_eax = mcp->mc_eax;
 2469                 tp->tf_eip = mcp->mc_eip;
 2470                 tp->tf_eflags = eflags;
 2471                 tp->tf_esp = mcp->mc_esp;
 2472                 tp->tf_ss = mcp->mc_ss;
 2473                 td->td_pcb->pcb_gs = mcp->mc_gs;
 2474                 ret = 0;
 2475         }
 2476         return (ret);
 2477 }
 2478 
 2479 static void
 2480 get_fpcontext(struct thread *td, mcontext_t *mcp)
 2481 {
 2482 #ifndef DEV_NPX
 2483         mcp->mc_fpformat = _MC_FPFMT_NODEV;
 2484         mcp->mc_ownedfp = _MC_FPOWNED_NONE;
 2485 #else
 2486         union savefpu *addr;
 2487 
 2488         /*
 2489          * XXX mc_fpstate might be misaligned, since its declaration is not
 2490          * unportabilized using __attribute__((aligned(16))) like the
 2491          * declaration of struct savemm, and anyway, alignment doesn't work
 2492          * for auto variables since we don't use gcc's pessimal stack
 2493          * alignment.  Work around this by abusing the spare fields after
 2494          * mcp->mc_fpstate.
 2495          *
 2496          * XXX unpessimize most cases by only aligning when fxsave might be
 2497          * called, although this requires knowing too much about
 2498          * npxgetregs()'s internals.
 2499          */
 2500         addr = (union savefpu *)&mcp->mc_fpstate;
 2501         if (td == PCPU_GET(fpcurthread) &&
 2502 #ifdef CPU_ENABLE_SSE
 2503             cpu_fxsr &&
 2504 #endif
 2505             ((uintptr_t)(void *)addr & 0xF)) {
 2506                 do
 2507                         addr = (void *)((char *)addr + 4);
 2508                 while ((uintptr_t)(void *)addr & 0xF);
 2509         }
 2510         mcp->mc_ownedfp = npxgetregs(td, addr);
 2511         if (addr != (union savefpu *)&mcp->mc_fpstate) {
 2512                 bcopy(addr, &mcp->mc_fpstate, sizeof(mcp->mc_fpstate));
 2513                 bzero(&mcp->mc_spare2, sizeof(mcp->mc_spare2));
 2514         }
 2515         mcp->mc_fpformat = npxformat();
 2516 #endif
 2517 }
 2518 
 2519 static int
 2520 set_fpcontext(struct thread *td, const mcontext_t *mcp)
 2521 {
 2522         union savefpu *addr;
 2523 
 2524         if (mcp->mc_fpformat == _MC_FPFMT_NODEV)
 2525                 return (0);
 2526         else if (mcp->mc_fpformat != _MC_FPFMT_387 &&
 2527             mcp->mc_fpformat != _MC_FPFMT_XMM)
 2528                 return (EINVAL);
 2529         else if (mcp->mc_ownedfp == _MC_FPOWNED_NONE)
 2530                 /* We don't care what state is left in the FPU or PCB. */
 2531                 fpstate_drop(td);
 2532         else if (mcp->mc_ownedfp == _MC_FPOWNED_FPU ||
 2533             mcp->mc_ownedfp == _MC_FPOWNED_PCB) {
 2534                 /* XXX align as above. */
 2535                 addr = (union savefpu *)&mcp->mc_fpstate;
 2536                 if (td == PCPU_GET(fpcurthread) &&
 2537 #ifdef CPU_ENABLE_SSE
 2538                     cpu_fxsr &&
 2539 #endif
 2540                     ((uintptr_t)(void *)addr & 0xF)) {
 2541                         do
 2542                                 addr = (void *)((char *)addr + 4);
 2543                         while ((uintptr_t)(void *)addr & 0xF);
 2544                         bcopy(&mcp->mc_fpstate, addr, sizeof(mcp->mc_fpstate));
 2545                 }
 2546 #ifdef DEV_NPX
 2547 #ifdef CPU_ENABLE_SSE
 2548                 if (cpu_fxsr)
 2549                         addr->sv_xmm.sv_env.en_mxcsr &= cpu_mxcsr_mask;
 2550 #endif
 2551                 /*
 2552                  * XXX we violate the dubious requirement that npxsetregs()
 2553                  * be called with interrupts disabled.
 2554                  */
 2555                 npxsetregs(td, addr);
 2556 #endif
 2557                 /*
 2558                  * Don't bother putting things back where they were in the
 2559                  * misaligned case, since we know that the caller won't use
 2560                  * them again.
 2561                  */
 2562         } else
 2563                 return (EINVAL);
 2564         return (0);
 2565 }
 2566 
 2567 static void
 2568 fpstate_drop(struct thread *td)
 2569 {
 2570         register_t s;
 2571 
 2572         s = intr_disable();
 2573 #ifdef DEV_NPX
 2574         if (PCPU_GET(fpcurthread) == td)
 2575                 npxdrop();
 2576 #endif
 2577         /*
 2578          * XXX force a full drop of the npx.  The above only drops it if we
 2579          * owned it.  npxgetregs() has the same bug in the !cpu_fxsr case.
 2580          *
 2581          * XXX I don't much like npxgetregs()'s semantics of doing a full
 2582          * drop.  Dropping only to the pcb matches fnsave's behaviour.
 2583          * We only need to drop to !PCB_INITDONE in sendsig().  But
 2584          * sendsig() is the only caller of npxgetregs()... perhaps we just
 2585          * have too many layers.
 2586          */
 2587         curthread->td_pcb->pcb_flags &= ~PCB_NPXINITDONE;
 2588         intr_restore(s);
 2589 }
 2590 
 2591 int
 2592 fill_dbregs(struct thread *td, struct dbreg *dbregs)
 2593 {
 2594         struct pcb *pcb;
 2595 
 2596         if (td == NULL) {
 2597                 dbregs->dr[0] = rdr0();
 2598                 dbregs->dr[1] = rdr1();
 2599                 dbregs->dr[2] = rdr2();
 2600                 dbregs->dr[3] = rdr3();
 2601                 dbregs->dr[4] = rdr4();
 2602                 dbregs->dr[5] = rdr5();
 2603                 dbregs->dr[6] = rdr6();
 2604                 dbregs->dr[7] = rdr7();
 2605         } else {
 2606                 pcb = td->td_pcb;
 2607                 dbregs->dr[0] = pcb->pcb_dr0;
 2608                 dbregs->dr[1] = pcb->pcb_dr1;
 2609                 dbregs->dr[2] = pcb->pcb_dr2;
 2610                 dbregs->dr[3] = pcb->pcb_dr3;
 2611                 dbregs->dr[4] = 0;
 2612                 dbregs->dr[5] = 0;
 2613                 dbregs->dr[6] = pcb->pcb_dr6;
 2614                 dbregs->dr[7] = pcb->pcb_dr7;
 2615         }
 2616         return (0);
 2617 }
 2618 
 2619 int
 2620 set_dbregs(struct thread *td, struct dbreg *dbregs)
 2621 {
 2622         struct pcb *pcb;
 2623         int i;
 2624 
 2625         if (td == NULL) {
 2626                 load_dr0(dbregs->dr[0]);
 2627                 load_dr1(dbregs->dr[1]);
 2628                 load_dr2(dbregs->dr[2]);
 2629                 load_dr3(dbregs->dr[3]);
 2630                 load_dr4(dbregs->dr[4]);
 2631                 load_dr5(dbregs->dr[5]);
 2632                 load_dr6(dbregs->dr[6]);
 2633                 load_dr7(dbregs->dr[7]);
 2634         } else {
 2635                 /*
 2636                  * Don't let an illegal value for dr7 get set.  Specifically,
 2637                  * check for undefined settings.  Setting these bit patterns
 2638                  * result in undefined behaviour and can lead to an unexpected
 2639                  * TRCTRAP.
 2640                  */
 2641                 for (i = 0; i < 4; i++) {
 2642                         if (DBREG_DR7_ACCESS(dbregs->dr[7], i) == 0x02)
 2643                                 return (EINVAL);
 2644                         if (DBREG_DR7_LEN(dbregs->dr[7], i) == 0x02)
 2645                                 return (EINVAL);
 2646                 }
 2647                 
 2648                 pcb = td->td_pcb;
 2649                 
 2650                 /*
 2651                  * Don't let a process set a breakpoint that is not within the
 2652                  * process's address space.  If a process could do this, it
 2653                  * could halt the system by setting a breakpoint in the kernel
 2654                  * (if ddb was enabled).  Thus, we need to check to make sure
 2655                  * that no breakpoints are being enabled for addresses outside
 2656                  * process's address space.
 2657                  *
 2658                  * XXX - what about when the watched area of the user's
 2659                  * address space is written into from within the kernel
 2660                  * ... wouldn't that still cause a breakpoint to be generated
 2661                  * from within kernel mode?
 2662                  */
 2663 
 2664                 if (DBREG_DR7_ENABLED(dbregs->dr[7], 0)) {
 2665                         /* dr0 is enabled */
 2666                         if (dbregs->dr[0] >= VM_MAXUSER_ADDRESS)
 2667                                 return (EINVAL);
 2668                 }
 2669                         
 2670                 if (DBREG_DR7_ENABLED(dbregs->dr[7], 1)) {
 2671                         /* dr1 is enabled */
 2672                         if (dbregs->dr[1] >= VM_MAXUSER_ADDRESS)
 2673                                 return (EINVAL);
 2674                 }
 2675                         
 2676                 if (DBREG_DR7_ENABLED(dbregs->dr[7], 2)) {
 2677                         /* dr2 is enabled */
 2678                         if (dbregs->dr[2] >= VM_MAXUSER_ADDRESS)
 2679                                 return (EINVAL);
 2680                 }
 2681                         
 2682                 if (DBREG_DR7_ENABLED(dbregs->dr[7], 3)) {
 2683                         /* dr3 is enabled */
 2684                         if (dbregs->dr[3] >= VM_MAXUSER_ADDRESS)
 2685                                 return (EINVAL);
 2686                 }
 2687 
 2688                 pcb->pcb_dr0 = dbregs->dr[0];
 2689                 pcb->pcb_dr1 = dbregs->dr[1];
 2690                 pcb->pcb_dr2 = dbregs->dr[2];
 2691                 pcb->pcb_dr3 = dbregs->dr[3];
 2692                 pcb->pcb_dr6 = dbregs->dr[6];
 2693                 pcb->pcb_dr7 = dbregs->dr[7];
 2694 
 2695                 pcb->pcb_flags |= PCB_DBREGS;
 2696         }
 2697 
 2698         return (0);
 2699 }
 2700 
 2701 /*
 2702  * Return > 0 if a hardware breakpoint has been hit, and the
 2703  * breakpoint was in user space.  Return 0, otherwise.
 2704  */
 2705 int
 2706 user_dbreg_trap(void)
 2707 {
 2708         u_int32_t dr7, dr6; /* debug registers dr6 and dr7 */
 2709         u_int32_t bp;       /* breakpoint bits extracted from dr6 */
 2710         int nbp;            /* number of breakpoints that triggered */
 2711         caddr_t addr[4];    /* breakpoint addresses */
 2712         int i;
 2713         
 2714         dr7 = rdr7();
 2715         if ((dr7 & 0x000000ff) == 0) {
 2716                 /*
 2717                  * all GE and LE bits in the dr7 register are zero,
 2718                  * thus the trap couldn't have been caused by the
 2719                  * hardware debug registers
 2720                  */
 2721                 return 0;
 2722         }
 2723 
 2724         nbp = 0;
 2725         dr6 = rdr6();
 2726         bp = dr6 & 0x0000000f;
 2727 
 2728         if (!bp) {
 2729                 /*
 2730                  * None of the breakpoint bits are set meaning this
 2731                  * trap was not caused by any of the debug registers
 2732                  */
 2733                 return 0;
 2734         }
 2735 
 2736         /*
 2737          * at least one of the breakpoints were hit, check to see
 2738          * which ones and if any of them are user space addresses
 2739          */
 2740 
 2741         if (bp & 0x01) {
 2742                 addr[nbp++] = (caddr_t)rdr0();
 2743         }
 2744         if (bp & 0x02) {
 2745                 addr[nbp++] = (caddr_t)rdr1();
 2746         }
 2747         if (bp & 0x04) {
 2748                 addr[nbp++] = (caddr_t)rdr2();
 2749         }
 2750         if (bp & 0x08) {
 2751                 addr[nbp++] = (caddr_t)rdr3();
 2752         }
 2753 
 2754         for (i = 0; i < nbp; i++) {
 2755                 if (addr[i] < (caddr_t)VM_MAXUSER_ADDRESS) {
 2756                         /*
 2757                          * addr[i] is in user space
 2758                          */
 2759                         return nbp;
 2760                 }
 2761         }
 2762 
 2763         /*
 2764          * None of the breakpoints are in user space.
 2765          */
 2766         return 0;
 2767 }
 2768 
 2769 #ifdef KDB
 2770 
 2771 /*
 2772  * Provide inb() and outb() as functions.  They are normally only
 2773  * available as macros calling inlined functions, thus cannot be
 2774  * called from the debugger.
 2775  *
 2776  * The actual code is stolen from <machine/cpufunc.h>, and de-inlined.
 2777  */
 2778 
 2779 #undef inb
 2780 #undef outb
 2781 
 2782 /* silence compiler warnings */
 2783 u_char inb(u_int);
 2784 void outb(u_int, u_char);
 2785 
 2786 u_char
 2787 inb(u_int port)
 2788 {
 2789         u_char  data;
 2790         /*
 2791          * We use %%dx and not %1 here because i/o is done at %dx and not at
 2792          * %edx, while gcc generates inferior code (movw instead of movl)
 2793          * if we tell it to load (u_short) port.
 2794          */
 2795         __asm __volatile("inb %%dx,%0" : "=a" (data) : "d" (port));
 2796         return (data);
 2797 }
 2798 
 2799 void
 2800 outb(u_int port, u_char data)
 2801 {
 2802         u_char  al;
 2803         /*
 2804          * Use an unnecessary assignment to help gcc's register allocator.
 2805          * This make a large difference for gcc-1.40 and a tiny difference
 2806          * for gcc-2.6.0.  For gcc-1.40, al had to be ``asm("ax")'' for
 2807          * best results.  gcc-2.6.0 can't handle this.
 2808          */
 2809         al = data;
 2810         __asm __volatile("outb %0,%%dx" : : "a" (al), "d" (port));
 2811 }
 2812 
 2813 #endif /* KDB */

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