The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


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FreeBSD/Linux Kernel Cross Reference
sys/amd64/amd64/machdep.c

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    1 /*-
    2  * Copyright (c) 2003 Peter Wemm.
    3  * Copyright (c) 1992 Terrence R. Lambert.
    4  * Copyright (c) 1982, 1987, 1990 The Regents of the University of California.
    5  * All rights reserved.
    6  *
    7  * This code is derived from software contributed to Berkeley by
    8  * William Jolitz.
    9  *
   10  * Redistribution and use in source and binary forms, with or without
   11  * modification, are permitted provided that the following conditions
   12  * are met:
   13  * 1. Redistributions of source code must retain the above copyright
   14  *    notice, this list of conditions and the following disclaimer.
   15  * 2. Redistributions in binary form must reproduce the above copyright
   16  *    notice, this list of conditions and the following disclaimer in the
   17  *    documentation and/or other materials provided with the distribution.
   18  * 3. All advertising materials mentioning features or use of this software
   19  *    must display the following acknowledgement:
   20  *      This product includes software developed by the University of
   21  *      California, Berkeley and its contributors.
   22  * 4. Neither the name of the University nor the names of its contributors
   23  *    may be used to endorse or promote products derived from this software
   24  *    without specific prior written permission.
   25  *
   26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   36  * SUCH DAMAGE.
   37  *
   38  *      from: @(#)machdep.c     7.4 (Berkeley) 6/3/91
   39  */
   40 
   41 #include <sys/cdefs.h>
   42 __FBSDID("$FreeBSD: releng/5.3/sys/amd64/amd64/machdep.c 144698 2005-04-06 01:06:44Z cperciva $");
   43 
   44 #include "opt_atalk.h"
   45 #include "opt_atpic.h"
   46 #include "opt_compat.h"
   47 #include "opt_cpu.h"
   48 #include "opt_ddb.h"
   49 #include "opt_inet.h"
   50 #include "opt_ipx.h"
   51 #include "opt_isa.h"
   52 #include "opt_kstack_pages.h"
   53 #include "opt_maxmem.h"
   54 #include "opt_msgbuf.h"
   55 #include "opt_perfmon.h"
   56 
   57 #include <sys/param.h>
   58 #include <sys/systm.h>
   59 #include <sys/sysproto.h>
   60 #include <sys/signalvar.h>
   61 #include <sys/imgact.h>
   62 #include <sys/kdb.h>
   63 #include <sys/kernel.h>
   64 #include <sys/ktr.h>
   65 #include <sys/linker.h>
   66 #include <sys/lock.h>
   67 #include <sys/malloc.h>
   68 #include <sys/memrange.h>
   69 #include <sys/mutex.h>
   70 #include <sys/pcpu.h>
   71 #include <sys/proc.h>
   72 #include <sys/bio.h>
   73 #include <sys/buf.h>
   74 #include <sys/reboot.h>
   75 #include <sys/callout.h>
   76 #include <sys/msgbuf.h>
   77 #include <sys/sched.h>
   78 #include <sys/sysent.h>
   79 #include <sys/sysctl.h>
   80 #include <sys/ucontext.h>
   81 #include <sys/vmmeter.h>
   82 #include <sys/bus.h>
   83 #include <sys/eventhandler.h>
   84 
   85 #include <vm/vm.h>
   86 #include <vm/vm_param.h>
   87 #include <vm/vm_kern.h>
   88 #include <vm/vm_object.h>
   89 #include <vm/vm_page.h>
   90 #include <vm/vm_map.h>
   91 #include <vm/vm_pager.h>
   92 #include <vm/vm_extern.h>
   93 
   94 #include <sys/user.h>
   95 #include <sys/exec.h>
   96 #include <sys/cons.h>
   97 
   98 #ifdef DDB
   99 #ifndef KDB
  100 #error KDB must be enabled in order for DDB to work!
  101 #endif
  102 #endif
  103 #include <ddb/ddb.h>
  104 
  105 #include <net/netisr.h>
  106 
  107 #include <machine/cpu.h>
  108 #include <machine/cputypes.h>
  109 #include <machine/reg.h>
  110 #include <machine/clock.h>
  111 #include <machine/specialreg.h>
  112 #include <machine/intr_machdep.h>
  113 #include <machine/md_var.h>
  114 #include <machine/metadata.h>
  115 #include <machine/proc.h>
  116 #ifdef PERFMON
  117 #include <machine/perfmon.h>
  118 #endif
  119 #include <machine/tss.h>
  120 #ifdef SMP
  121 #include <machine/smp.h>
  122 #endif
  123 
  124 #include <amd64/isa/icu.h>
  125 
  126 #include <isa/isareg.h>
  127 #include <isa/rtc.h>
  128 #include <sys/ptrace.h>
  129 #include <machine/sigframe.h>
  130 
  131 /* Sanity check for __curthread() */
  132 CTASSERT(offsetof(struct pcpu, pc_curthread) == 0);
  133 
  134 extern u_int64_t hammer_time(u_int64_t, u_int64_t);
  135 extern void dblfault_handler(void);
  136 
  137 extern void printcpuinfo(void); /* XXX header file */
  138 extern void identify_cpu(void);
  139 extern void panicifcpuunsupported(void);
  140 
  141 #define CS_SECURE(cs)           (ISPL(cs) == SEL_UPL)
  142 #define EFL_SECURE(ef, oef)     ((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0)
  143 
  144 static void cpu_startup(void *);
  145 static void get_fpcontext(struct thread *td, mcontext_t *mcp);
  146 static int  set_fpcontext(struct thread *td, const mcontext_t *mcp);
  147 SYSINIT(cpu, SI_SUB_CPU, SI_ORDER_FIRST, cpu_startup, NULL)
  148 
  149 #ifdef DDB
  150 extern vm_offset_t ksym_start, ksym_end;
  151 #endif
  152 
  153 int     _udatasel, _ucodesel, _ucode32sel;
  154 
  155 int cold = 1;
  156 
  157 long Maxmem = 0;
  158 
  159 vm_paddr_t phys_avail[20];
  160 
  161 /* must be 2 less so 0 0 can signal end of chunks */
  162 #define PHYS_AVAIL_ARRAY_END ((sizeof(phys_avail) / sizeof(vm_offset_t)) - 2)
  163 
  164 struct kva_md_info kmi;
  165 
  166 static struct trapframe proc0_tf;
  167 struct region_descriptor r_gdt, r_idt;
  168 
  169 struct pcpu __pcpu[MAXCPU];
  170 
  171 struct mtx icu_lock;
  172 
  173 struct mem_range_softc mem_range_softc;
  174 
  175 static void
  176 cpu_startup(dummy)
  177         void *dummy;
  178 {
  179         /*
  180          * Good {morning,afternoon,evening,night}.
  181          */
  182         startrtclock();
  183         printcpuinfo();
  184         panicifcpuunsupported();
  185 #ifdef PERFMON
  186         perfmon_init();
  187 #endif
  188         printf("real memory  = %ju (%ju MB)\n", ptoa((uintmax_t)Maxmem),
  189             ptoa((uintmax_t)Maxmem) / 1048576);
  190         /*
  191          * Display any holes after the first chunk of extended memory.
  192          */
  193         if (bootverbose) {
  194                 int indx;
  195 
  196                 printf("Physical memory chunk(s):\n");
  197                 for (indx = 0; phys_avail[indx + 1] != 0; indx += 2) {
  198                         vm_paddr_t size;
  199 
  200                         size = phys_avail[indx + 1] - phys_avail[indx];
  201                         printf(
  202                             "0x%016jx - 0x%016jx, %ju bytes (%ju pages)\n",
  203                             (uintmax_t)phys_avail[indx],
  204                             (uintmax_t)phys_avail[indx + 1] - 1,
  205                             (uintmax_t)size, (uintmax_t)size / PAGE_SIZE);
  206                 }
  207         }
  208 
  209         vm_ksubmap_init(&kmi);
  210 
  211         printf("avail memory = %ju (%ju MB)\n",
  212             ptoa((uintmax_t)cnt.v_free_count),
  213             ptoa((uintmax_t)cnt.v_free_count) / 1048576);
  214 
  215         /*
  216          * Set up buffers, so they can be used to read disk labels.
  217          */
  218         bufinit();
  219         vm_pager_bufferinit();
  220 
  221         cpu_setregs();
  222 }
  223 
  224 /*
  225  * Send an interrupt to process.
  226  *
  227  * Stack is set up to allow sigcode stored
  228  * at top to call routine, followed by kcall
  229  * to sigreturn routine below.  After sigreturn
  230  * resets the signal mask, the stack, and the
  231  * frame pointer, it returns to the user
  232  * specified pc, psl.
  233  */
  234 void
  235 sendsig(catcher, sig, mask, code)
  236         sig_t catcher;
  237         int sig;
  238         sigset_t *mask;
  239         u_long code;
  240 {
  241         struct sigframe sf, *sfp;
  242         struct proc *p;
  243         struct thread *td;
  244         struct sigacts *psp;
  245         char *sp;
  246         struct trapframe *regs;
  247         int oonstack;
  248 
  249         td = curthread;
  250         p = td->td_proc;
  251         PROC_LOCK_ASSERT(p, MA_OWNED);
  252         psp = p->p_sigacts;
  253         mtx_assert(&psp->ps_mtx, MA_OWNED);
  254         regs = td->td_frame;
  255         oonstack = sigonstack(regs->tf_rsp);
  256 
  257         /* Save user context. */
  258         bzero(&sf, sizeof(sf));
  259         sf.sf_uc.uc_sigmask = *mask;
  260         sf.sf_uc.uc_stack = td->td_sigstk;
  261         sf.sf_uc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK)
  262             ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
  263         sf.sf_uc.uc_mcontext.mc_onstack = (oonstack) ? 1 : 0;
  264         bcopy(regs, &sf.sf_uc.uc_mcontext.mc_rdi, sizeof(*regs));
  265         sf.sf_uc.uc_mcontext.mc_len = sizeof(sf.sf_uc.uc_mcontext); /* magic */
  266         get_fpcontext(td, &sf.sf_uc.uc_mcontext);
  267         fpstate_drop(td);
  268 
  269         /* Allocate space for the signal handler context. */
  270         if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack &&
  271             SIGISMEMBER(psp->ps_sigonstack, sig)) {
  272                 sp = td->td_sigstk.ss_sp +
  273                     td->td_sigstk.ss_size - sizeof(struct sigframe);
  274 #if defined(COMPAT_43)
  275                 td->td_sigstk.ss_flags |= SS_ONSTACK;
  276 #endif
  277         } else
  278                 sp = (char *)regs->tf_rsp - sizeof(struct sigframe) - 128;
  279         /* Align to 16 bytes. */
  280         sfp = (struct sigframe *)((unsigned long)sp & ~0xFul);
  281 
  282         /* Translate the signal if appropriate. */
  283         if (p->p_sysent->sv_sigtbl && sig <= p->p_sysent->sv_sigsize)
  284                 sig = p->p_sysent->sv_sigtbl[_SIG_IDX(sig)];
  285 
  286         /* Build the argument list for the signal handler. */
  287         regs->tf_rdi = sig;                     /* arg 1 in %rdi */
  288         regs->tf_rdx = (register_t)&sfp->sf_uc; /* arg 3 in %rdx */
  289         if (SIGISMEMBER(psp->ps_siginfo, sig)) {
  290                 /* Signal handler installed with SA_SIGINFO. */
  291                 regs->tf_rsi = (register_t)&sfp->sf_si; /* arg 2 in %rsi */
  292                 sf.sf_ahu.sf_action = (__siginfohandler_t *)catcher;
  293 
  294                 /* Fill in POSIX parts */
  295                 sf.sf_si.si_signo = sig;
  296                 sf.sf_si.si_code = code;
  297                 regs->tf_rcx = regs->tf_addr;   /* arg 4 in %rcx */
  298         } else {
  299                 /* Old FreeBSD-style arguments. */
  300                 regs->tf_rsi = code;            /* arg 2 in %rsi */
  301                 regs->tf_rcx = regs->tf_addr;   /* arg 4 in %rcx */
  302                 sf.sf_ahu.sf_handler = catcher;
  303         }
  304         mtx_unlock(&psp->ps_mtx);
  305         PROC_UNLOCK(p);
  306 
  307         /*
  308          * Copy the sigframe out to the user's stack.
  309          */
  310         if (copyout(&sf, sfp, sizeof(*sfp)) != 0) {
  311 #ifdef DEBUG
  312                 printf("process %ld has trashed its stack\n", (long)p->p_pid);
  313 #endif
  314                 PROC_LOCK(p);
  315                 sigexit(td, SIGILL);
  316         }
  317 
  318         regs->tf_rsp = (long)sfp;
  319         regs->tf_rip = PS_STRINGS - *(p->p_sysent->sv_szsigcode);
  320         regs->tf_rflags &= ~PSL_T;
  321         regs->tf_cs = _ucodesel;
  322         PROC_LOCK(p);
  323         mtx_lock(&psp->ps_mtx);
  324 }
  325 
  326 /*
  327  * Build siginfo_t for SA thread
  328  */
  329 void
  330 cpu_thread_siginfo(int sig, u_long code, siginfo_t *si)
  331 {
  332         struct proc *p;
  333         struct thread *td;
  334         struct trapframe *regs;
  335 
  336         td = curthread;
  337         p = td->td_proc;
  338         regs = td->td_frame;
  339         PROC_LOCK_ASSERT(p, MA_OWNED);
  340 
  341         bzero(si, sizeof(*si));
  342         si->si_signo = sig;
  343         si->si_code = code;
  344         si->si_addr = (void *)regs->tf_addr;
  345         /* XXXKSE fill other fields */
  346 }
  347 
  348 /*
  349  * System call to cleanup state after a signal
  350  * has been taken.  Reset signal mask and
  351  * stack state from context left by sendsig (above).
  352  * Return to previous pc and psl as specified by
  353  * context left by sendsig. Check carefully to
  354  * make sure that the user has not modified the
  355  * state to gain improper privileges.
  356  *
  357  * MPSAFE
  358  */
  359 int
  360 sigreturn(td, uap)
  361         struct thread *td;
  362         struct sigreturn_args /* {
  363                 const __ucontext *sigcntxp;
  364         } */ *uap;
  365 {
  366         ucontext_t uc;
  367         struct proc *p = td->td_proc;
  368         struct trapframe *regs;
  369         const ucontext_t *ucp;
  370         long rflags;
  371         int cs, error, ret;
  372 
  373         error = copyin(uap->sigcntxp, &uc, sizeof(uc));
  374         if (error != 0)
  375                 return (error);
  376         ucp = &uc;
  377         regs = td->td_frame;
  378         rflags = ucp->uc_mcontext.mc_rflags;
  379         /*
  380          * Don't allow users to change privileged or reserved flags.
  381          */
  382         /*
  383          * XXX do allow users to change the privileged flag PSL_RF.
  384          * The cpu sets PSL_RF in tf_rflags for faults.  Debuggers
  385          * should sometimes set it there too.  tf_rflags is kept in
  386          * the signal context during signal handling and there is no
  387          * other place to remember it, so the PSL_RF bit may be
  388          * corrupted by the signal handler without us knowing.
  389          * Corruption of the PSL_RF bit at worst causes one more or
  390          * one less debugger trap, so allowing it is fairly harmless.
  391          */
  392         if (!EFL_SECURE(rflags & ~PSL_RF, regs->tf_rflags & ~PSL_RF)) {
  393                 printf("sigreturn: rflags = 0x%lx\n", rflags);
  394                 return (EINVAL);
  395         }
  396 
  397         /*
  398          * Don't allow users to load a valid privileged %cs.  Let the
  399          * hardware check for invalid selectors, excess privilege in
  400          * other selectors, invalid %eip's and invalid %esp's.
  401          */
  402         cs = ucp->uc_mcontext.mc_cs;
  403         if (!CS_SECURE(cs)) {
  404                 printf("sigreturn: cs = 0x%x\n", cs);
  405                 trapsignal(td, SIGBUS, T_PROTFLT);
  406                 return (EINVAL);
  407         }
  408 
  409         ret = set_fpcontext(td, &ucp->uc_mcontext);
  410         if (ret != 0)
  411                 return (ret);
  412         bcopy(&ucp->uc_mcontext.mc_rdi, regs, sizeof(*regs));
  413 
  414         PROC_LOCK(p);
  415 #if defined(COMPAT_43)
  416         if (ucp->uc_mcontext.mc_onstack & 1)
  417                 td->td_sigstk.ss_flags |= SS_ONSTACK;
  418         else
  419                 td->td_sigstk.ss_flags &= ~SS_ONSTACK;
  420 #endif
  421 
  422         td->td_sigmask = ucp->uc_sigmask;
  423         SIG_CANTMASK(td->td_sigmask);
  424         signotify(td);
  425         PROC_UNLOCK(p);
  426         td->td_pcb->pcb_flags |= PCB_FULLCTX;
  427         return (EJUSTRETURN);
  428 }
  429 
  430 #ifdef COMPAT_FREEBSD4
  431 int
  432 freebsd4_sigreturn(struct thread *td, struct freebsd4_sigreturn_args *uap)
  433 {
  434  
  435         return sigreturn(td, (struct sigreturn_args *)uap);
  436 }
  437 #endif
  438 
  439 
  440 /*
  441  * Machine dependent boot() routine
  442  *
  443  * I haven't seen anything to put here yet
  444  * Possibly some stuff might be grafted back here from boot()
  445  */
  446 void
  447 cpu_boot(int howto)
  448 {
  449 }
  450 
  451 /*
  452  * Shutdown the CPU as much as possible
  453  */
  454 void
  455 cpu_halt(void)
  456 {
  457         for (;;)
  458                 __asm__ ("hlt");
  459 }
  460 
  461 /*
  462  * Hook to idle the CPU when possible.  In the SMP case we default to
  463  * off because a halted cpu will not currently pick up a new thread in the
  464  * run queue until the next timer tick.  If turned on this will result in
  465  * approximately a 4.2% loss in real time performance in buildworld tests
  466  * (but improves user and sys times oddly enough), and saves approximately
  467  * 5% in power consumption on an idle machine (tests w/2xCPU 1.1GHz P3).
  468  *
  469  * XXX we need to have a cpu mask of idle cpus and generate an IPI or
  470  * otherwise generate some sort of interrupt to wake up cpus sitting in HLT.
  471  * Then we can have our cake and eat it too.
  472  *
  473  * XXX I'm turning it on for SMP as well by default for now.  It seems to
  474  * help lock contention somewhat, and this is critical for HTT. -Peter
  475  */
  476 static int      cpu_idle_hlt = 1;
  477 SYSCTL_INT(_machdep, OID_AUTO, cpu_idle_hlt, CTLFLAG_RW,
  478     &cpu_idle_hlt, 0, "Idle loop HLT enable");
  479 
  480 static void
  481 cpu_idle_default(void)
  482 {
  483         /*
  484          * we must absolutely guarentee that hlt is the
  485          * absolute next instruction after sti or we
  486          * introduce a timing window.
  487          */
  488         __asm __volatile("sti; hlt");
  489 }
  490 
  491 /*
  492  * Note that we have to be careful here to avoid a race between checking
  493  * sched_runnable() and actually halting.  If we don't do this, we may waste
  494  * the time between calling hlt and the next interrupt even though there
  495  * is a runnable process.
  496  */
  497 void
  498 cpu_idle(void)
  499 {
  500 
  501         if (cpu_idle_hlt) {
  502                 disable_intr();
  503                 if (sched_runnable())
  504                         enable_intr();
  505                 else
  506                         (*cpu_idle_hook)();
  507         }
  508 }
  509 
  510 /* Other subsystems (e.g., ACPI) can hook this later. */
  511 void (*cpu_idle_hook)(void) = cpu_idle_default;
  512 
  513 /*
  514  * Clear registers on exec
  515  */
  516 void
  517 exec_setregs(td, entry, stack, ps_strings)
  518         struct thread *td;
  519         u_long entry;
  520         u_long stack;
  521         u_long ps_strings;
  522 {
  523         struct trapframe *regs = td->td_frame;
  524         struct pcb *pcb = td->td_pcb;
  525         
  526         wrmsr(MSR_FSBASE, 0);
  527         wrmsr(MSR_KGSBASE, 0);  /* User value while we're in the kernel */
  528         pcb->pcb_fsbase = 0;
  529         pcb->pcb_gsbase = 0;
  530         load_ds(_udatasel);
  531         load_es(_udatasel);
  532         load_fs(_udatasel);
  533         load_gs(_udatasel);
  534         pcb->pcb_ds = _udatasel;
  535         pcb->pcb_es = _udatasel;
  536         pcb->pcb_fs = _udatasel;
  537         pcb->pcb_gs = _udatasel;
  538 
  539         bzero((char *)regs, sizeof(struct trapframe));
  540         regs->tf_rip = entry;
  541         regs->tf_rsp = ((stack - 8) & ~0xFul) + 8;
  542         regs->tf_rdi = stack;           /* argv */
  543         regs->tf_rflags = PSL_USER | (regs->tf_rflags & PSL_T);
  544         regs->tf_ss = _udatasel;
  545         regs->tf_cs = _ucodesel;
  546 
  547         /*
  548          * Reset the hardware debug registers if they were in use.
  549          * They won't have any meaning for the newly exec'd process.
  550          */
  551         if (pcb->pcb_flags & PCB_DBREGS) {
  552                 pcb->pcb_dr0 = 0;
  553                 pcb->pcb_dr1 = 0;
  554                 pcb->pcb_dr2 = 0;
  555                 pcb->pcb_dr3 = 0;
  556                 pcb->pcb_dr6 = 0;
  557                 pcb->pcb_dr7 = 0;
  558                 if (pcb == PCPU_GET(curpcb)) {
  559                         /*
  560                          * Clear the debug registers on the running
  561                          * CPU, otherwise they will end up affecting
  562                          * the next process we switch to.
  563                          */
  564                         reset_dbregs();
  565                 }
  566                 pcb->pcb_flags &= ~PCB_DBREGS;
  567         }
  568 
  569         /*
  570          * Drop the FP state if we hold it, so that the process gets a
  571          * clean FP state if it uses the FPU again.
  572          */
  573         fpstate_drop(td);
  574 }
  575 
  576 void
  577 cpu_setregs(void)
  578 {
  579         register_t cr0;
  580 
  581         cr0 = rcr0();
  582         /*
  583          * CR0_MP, CR0_NE and CR0_TS are also set by npx_probe() for the
  584          * BSP.  See the comments there about why we set them.
  585          */
  586         cr0 |= CR0_MP | CR0_NE | CR0_TS;
  587         cr0 |= CR0_WP | CR0_AM;
  588         load_cr0(cr0);
  589 }
  590 
  591 static int
  592 sysctl_machdep_adjkerntz(SYSCTL_HANDLER_ARGS)
  593 {
  594         int error;
  595         error = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2,
  596                 req);
  597         if (!error && req->newptr)
  598                 resettodr();
  599         return (error);
  600 }
  601 
  602 SYSCTL_PROC(_machdep, CPU_ADJKERNTZ, adjkerntz, CTLTYPE_INT|CTLFLAG_RW,
  603         &adjkerntz, 0, sysctl_machdep_adjkerntz, "I", "");
  604 
  605 SYSCTL_INT(_machdep, CPU_DISRTCSET, disable_rtc_set,
  606         CTLFLAG_RW, &disable_rtc_set, 0, "");
  607 
  608 SYSCTL_INT(_machdep, CPU_WALLCLOCK, wall_cmos_clock,
  609         CTLFLAG_RW, &wall_cmos_clock, 0, "");
  610 
  611 /*
  612  * Initialize 386 and configure to run kernel
  613  */
  614 
  615 /*
  616  * Initialize segments & interrupt table
  617  */
  618 
  619 struct user_segment_descriptor gdt[NGDT * MAXCPU];/* global descriptor table */
  620 static struct gate_descriptor idt0[NIDT];
  621 struct gate_descriptor *idt = &idt0[0]; /* interrupt descriptor table */
  622 
  623 static char dblfault_stack[PAGE_SIZE] __aligned(16);
  624 
  625 struct amd64tss common_tss[MAXCPU];
  626 
  627 /* software prototypes -- in more palatable form */
  628 struct soft_segment_descriptor gdt_segs[] = {
  629 /* GNULL_SEL    0 Null Descriptor */
  630 {       0x0,                    /* segment base address  */
  631         0x0,                    /* length */
  632         0,                      /* segment type */
  633         0,                      /* segment descriptor priority level */
  634         0,                      /* segment descriptor present */
  635         0,                      /* long */
  636         0,                      /* default 32 vs 16 bit size */
  637         0                       /* limit granularity (byte/page units)*/ },
  638 /* GCODE_SEL    1 Code Descriptor for kernel */
  639 {       0x0,                    /* segment base address  */
  640         0xfffff,                /* length - all address space */
  641         SDT_MEMERA,             /* segment type */
  642         SEL_KPL,                /* segment descriptor priority level */
  643         1,                      /* segment descriptor present */
  644         1,                      /* long */
  645         0,                      /* default 32 vs 16 bit size */
  646         1                       /* limit granularity (byte/page units)*/ },
  647 /* GDATA_SEL    2 Data Descriptor for kernel */
  648 {       0x0,                    /* segment base address  */
  649         0xfffff,                /* length - all address space */
  650         SDT_MEMRWA,             /* segment type */
  651         SEL_KPL,                /* segment descriptor priority level */
  652         1,                      /* segment descriptor present */
  653         1,                      /* long */
  654         0,                      /* default 32 vs 16 bit size */
  655         1                       /* limit granularity (byte/page units)*/ },
  656 /* GUCODE32_SEL 3 32 bit Code Descriptor for user */
  657 {       0x0,                    /* segment base address  */
  658         0xfffff,                /* length - all address space */
  659         SDT_MEMERA,             /* segment type */
  660         SEL_UPL,                /* segment descriptor priority level */
  661         1,                      /* segment descriptor present */
  662         0,                      /* long */
  663         1,                      /* default 32 vs 16 bit size */
  664         1                       /* limit granularity (byte/page units)*/ },
  665 /* GUDATA_SEL   4 32/64 bit Data Descriptor for user */
  666 {       0x0,                    /* segment base address  */
  667         0xfffff,                /* length - all address space */
  668         SDT_MEMRWA,             /* segment type */
  669         SEL_UPL,                /* segment descriptor priority level */
  670         1,                      /* segment descriptor present */
  671         0,                      /* long */
  672         1,                      /* default 32 vs 16 bit size */
  673         1                       /* limit granularity (byte/page units)*/ },
  674 /* GUCODE_SEL   5 64 bit Code Descriptor for user */
  675 {       0x0,                    /* segment base address  */
  676         0xfffff,                /* length - all address space */
  677         SDT_MEMERA,             /* segment type */
  678         SEL_UPL,                /* segment descriptor priority level */
  679         1,                      /* segment descriptor present */
  680         1,                      /* long */
  681         0,                      /* default 32 vs 16 bit size */
  682         1                       /* limit granularity (byte/page units)*/ },
  683 /* GPROC0_SEL   6 Proc 0 Tss Descriptor */
  684 {
  685         0x0,                    /* segment base address */
  686         sizeof(struct amd64tss)-1,/* length - all address space */
  687         SDT_SYSTSS,             /* segment type */
  688         SEL_KPL,                /* segment descriptor priority level */
  689         1,                      /* segment descriptor present */
  690         0,                      /* long */
  691         0,                      /* unused - default 32 vs 16 bit size */
  692         0                       /* limit granularity (byte/page units)*/ },
  693 /* Actually, the TSS is a system descriptor which is double size */
  694 {       0x0,                    /* segment base address  */
  695         0x0,                    /* length */
  696         0,                      /* segment type */
  697         0,                      /* segment descriptor priority level */
  698         0,                      /* segment descriptor present */
  699         0,                      /* long */
  700         0,                      /* default 32 vs 16 bit size */
  701         0                       /* limit granularity (byte/page units)*/ },
  702 };
  703 
  704 void
  705 setidt(idx, func, typ, dpl, ist)
  706         int idx;
  707         inthand_t *func;
  708         int typ;
  709         int dpl;
  710         int ist;
  711 {
  712         struct gate_descriptor *ip;
  713 
  714         ip = idt + idx;
  715         ip->gd_looffset = (uintptr_t)func;
  716         ip->gd_selector = GSEL(GCODE_SEL, SEL_KPL);
  717         ip->gd_ist = ist;
  718         ip->gd_xx = 0;
  719         ip->gd_type = typ;
  720         ip->gd_dpl = dpl;
  721         ip->gd_p = 1;
  722         ip->gd_hioffset = ((uintptr_t)func)>>16 ;
  723 }
  724 
  725 #define IDTVEC(name)    __CONCAT(X,name)
  726 
  727 extern inthand_t
  728         IDTVEC(div), IDTVEC(dbg), IDTVEC(nmi), IDTVEC(bpt), IDTVEC(ofl),
  729         IDTVEC(bnd), IDTVEC(ill), IDTVEC(dna), IDTVEC(fpusegm),
  730         IDTVEC(tss), IDTVEC(missing), IDTVEC(stk), IDTVEC(prot),
  731         IDTVEC(page), IDTVEC(mchk), IDTVEC(rsvd), IDTVEC(fpu), IDTVEC(align),
  732         IDTVEC(xmm), IDTVEC(dblfault),
  733         IDTVEC(fast_syscall), IDTVEC(fast_syscall32);
  734 
  735 void
  736 sdtossd(sd, ssd)
  737         struct user_segment_descriptor *sd;
  738         struct soft_segment_descriptor *ssd;
  739 {
  740 
  741         ssd->ssd_base  = (sd->sd_hibase << 24) | sd->sd_lobase;
  742         ssd->ssd_limit = (sd->sd_hilimit << 16) | sd->sd_lolimit;
  743         ssd->ssd_type  = sd->sd_type;
  744         ssd->ssd_dpl   = sd->sd_dpl;
  745         ssd->ssd_p     = sd->sd_p;
  746         ssd->ssd_long  = sd->sd_long;
  747         ssd->ssd_def32 = sd->sd_def32;
  748         ssd->ssd_gran  = sd->sd_gran;
  749 }
  750 
  751 void
  752 ssdtosd(ssd, sd)
  753         struct soft_segment_descriptor *ssd;
  754         struct user_segment_descriptor *sd;
  755 {
  756 
  757         sd->sd_lobase = (ssd->ssd_base) & 0xffffff;
  758         sd->sd_hibase = (ssd->ssd_base >> 24) & 0xff;
  759         sd->sd_lolimit = (ssd->ssd_limit) & 0xffff;
  760         sd->sd_hilimit = (ssd->ssd_limit >> 16) & 0xf;
  761         sd->sd_type  = ssd->ssd_type;
  762         sd->sd_dpl   = ssd->ssd_dpl;
  763         sd->sd_p     = ssd->ssd_p;
  764         sd->sd_long  = ssd->ssd_long;
  765         sd->sd_def32 = ssd->ssd_def32;
  766         sd->sd_gran  = ssd->ssd_gran;
  767 }
  768 
  769 void
  770 ssdtosyssd(ssd, sd)
  771         struct soft_segment_descriptor *ssd;
  772         struct system_segment_descriptor *sd;
  773 {
  774 
  775         sd->sd_lobase = (ssd->ssd_base) & 0xffffff;
  776         sd->sd_hibase = (ssd->ssd_base >> 24) & 0xfffffffffful;
  777         sd->sd_lolimit = (ssd->ssd_limit) & 0xffff;
  778         sd->sd_hilimit = (ssd->ssd_limit >> 16) & 0xf;
  779         sd->sd_type  = ssd->ssd_type;
  780         sd->sd_dpl   = ssd->ssd_dpl;
  781         sd->sd_p     = ssd->ssd_p;
  782         sd->sd_gran  = ssd->ssd_gran;
  783 }
  784 
  785 #if !defined(DEV_ATPIC) && defined(DEV_ISA)
  786 #include <isa/isavar.h>
  787 u_int
  788 isa_irq_pending(void)
  789 {
  790 
  791         return (0);
  792 }
  793 #endif
  794 
  795 #define PHYSMAP_SIZE    (2 * 8)
  796 
  797 struct bios_smap {
  798         u_int64_t       base;
  799         u_int64_t       length;
  800         u_int32_t       type;
  801 } __packed;
  802 
  803 u_int basemem;
  804 
  805 /*
  806  * Populate the (physmap) array with base/bound pairs describing the
  807  * available physical memory in the system, then test this memory and
  808  * build the phys_avail array describing the actually-available memory.
  809  *
  810  * If we cannot accurately determine the physical memory map, then use
  811  * value from the 0xE801 call, and failing that, the RTC.
  812  *
  813  * Total memory size may be set by the kernel environment variable
  814  * hw.physmem or the compile-time define MAXMEM.
  815  *
  816  * XXX first should be vm_paddr_t.
  817  */
  818 static void
  819 getmemsize(caddr_t kmdp, u_int64_t first)
  820 {
  821         int i, physmap_idx, pa_indx;
  822         vm_paddr_t pa, physmap[PHYSMAP_SIZE];
  823         pt_entry_t *pte;
  824         char *cp;
  825         struct bios_smap *smapbase, *smap, *smapend;
  826         u_int32_t smapsize;
  827 
  828         bzero(physmap, sizeof(physmap));
  829         basemem = 0;
  830         physmap_idx = 0;
  831 
  832         /*
  833          * get memory map from INT 15:E820, kindly supplied by the loader.
  834          *
  835          * subr_module.c says:
  836          * "Consumer may safely assume that size value precedes data."
  837          * ie: an int32_t immediately precedes smap.
  838          */
  839         smapbase = (struct bios_smap *)preload_search_info(kmdp,
  840             MODINFO_METADATA | MODINFOMD_SMAP);
  841         if (smapbase == NULL)
  842                 panic("No BIOS smap info from loader!");
  843 
  844         smapsize = *((u_int32_t *)smapbase - 1);
  845         smapend = (struct bios_smap *)((uintptr_t)smapbase + smapsize);
  846 
  847         for (smap = smapbase; smap < smapend; smap++) {
  848                 if (boothowto & RB_VERBOSE)
  849                         printf("SMAP type=%02x base=%016lx len=%016lx\n",
  850                             smap->type, smap->base, smap->length);
  851 
  852                 if (smap->type != 0x01)
  853                         continue;
  854 
  855                 if (smap->length == 0)
  856                         continue;
  857 
  858                 for (i = 0; i <= physmap_idx; i += 2) {
  859                         if (smap->base < physmap[i + 1]) {
  860                                 if (boothowto & RB_VERBOSE)
  861                                         printf(
  862         "Overlapping or non-montonic memory region, ignoring second region\n");
  863                                 goto next_run;
  864                         }
  865                 }
  866 
  867                 if (smap->base == physmap[physmap_idx + 1]) {
  868                         physmap[physmap_idx + 1] += smap->length;
  869 next_run:
  870                         continue;
  871                 }
  872 
  873                 physmap_idx += 2;
  874                 if (physmap_idx == PHYSMAP_SIZE) {
  875                         printf(
  876                 "Too many segments in the physical address map, giving up\n");
  877                         break;
  878                 }
  879                 physmap[physmap_idx] = smap->base;
  880                 physmap[physmap_idx + 1] = smap->base + smap->length;
  881         }
  882 
  883         /*
  884          * Find the 'base memory' segment for SMP
  885          */
  886         basemem = 0;
  887         for (i = 0; i <= physmap_idx; i += 2) {
  888                 if (physmap[i] == 0x00000000) {
  889                         basemem = physmap[i + 1] / 1024;
  890                         break;
  891                 }
  892         }
  893         if (basemem == 0)
  894                 panic("BIOS smap did not include a basemem segment!");
  895 
  896 #ifdef SMP
  897         /* make hole for AP bootstrap code */
  898         physmap[1] = mp_bootaddress(physmap[1] / 1024);
  899 #endif
  900 
  901         /*
  902          * Maxmem isn't the "maximum memory", it's one larger than the
  903          * highest page of the physical address space.  It should be
  904          * called something like "Maxphyspage".  We may adjust this
  905          * based on ``hw.physmem'' and the results of the memory test.
  906          */
  907         Maxmem = atop(physmap[physmap_idx + 1]);
  908 
  909 #ifdef MAXMEM
  910         Maxmem = MAXMEM / 4;
  911 #endif
  912 
  913         /*
  914          * hw.physmem is a size in bytes; we also allow k, m, and g suffixes
  915          * for the appropriate modifiers.  This overrides MAXMEM.
  916          */
  917         cp = getenv("hw.physmem");
  918         if (cp != NULL) {
  919                 u_int64_t AllowMem, sanity;
  920                 char *ep;
  921 
  922                 sanity = AllowMem = strtouq(cp, &ep, 0);
  923                 if ((ep != cp) && (*ep != 0)) {
  924                         switch(*ep) {
  925                         case 'g':
  926                         case 'G':
  927                                 AllowMem <<= 10;
  928                         case 'm':
  929                         case 'M':
  930                                 AllowMem <<= 10;
  931                         case 'k':
  932                         case 'K':
  933                                 AllowMem <<= 10;
  934                                 break;
  935                         default:
  936                                 AllowMem = sanity = 0;
  937                         }
  938                         if (AllowMem < sanity)
  939                                 AllowMem = 0;
  940                 }
  941                 if (AllowMem == 0)
  942                         printf("Ignoring invalid memory size of '%s'\n", cp);
  943                 else
  944                         Maxmem = atop(AllowMem);
  945                 freeenv(cp);
  946         }
  947 
  948         if (atop(physmap[physmap_idx + 1]) != Maxmem &&
  949             (boothowto & RB_VERBOSE))
  950                 printf("Physical memory use set to %ldK\n", Maxmem * 4);
  951 
  952         /*
  953          * If Maxmem has been increased beyond what the system has detected,
  954          * extend the last memory segment to the new limit.
  955          */
  956         if (atop(physmap[physmap_idx + 1]) < Maxmem)
  957                 physmap[physmap_idx + 1] = ptoa((vm_paddr_t)Maxmem);
  958 
  959         /* call pmap initialization to make new kernel address space */
  960         pmap_bootstrap(&first);
  961 
  962         /*
  963          * Size up each available chunk of physical memory.
  964          */
  965         physmap[0] = PAGE_SIZE;         /* mask off page 0 */
  966         pa_indx = 0;
  967         phys_avail[pa_indx++] = physmap[0];
  968         phys_avail[pa_indx] = physmap[0];
  969         pte = CMAP1;
  970 
  971         /*
  972          * physmap is in bytes, so when converting to page boundaries,
  973          * round up the start address and round down the end address.
  974          */
  975         for (i = 0; i <= physmap_idx; i += 2) {
  976                 vm_paddr_t end;
  977 
  978                 end = ptoa((vm_paddr_t)Maxmem);
  979                 if (physmap[i + 1] < end)
  980                         end = trunc_page(physmap[i + 1]);
  981                 for (pa = round_page(physmap[i]); pa < end; pa += PAGE_SIZE) {
  982                         int tmp, page_bad;
  983                         int *ptr = (int *)CADDR1;
  984 
  985                         /*
  986                          * block out kernel memory as not available.
  987                          */
  988                         if (pa >= 0x100000 && pa < first)
  989                                 continue;
  990 
  991                         page_bad = FALSE;
  992 
  993                         /*
  994                          * map page into kernel: valid, read/write,non-cacheable
  995                          */
  996                         *pte = pa | PG_V | PG_RW | PG_N;
  997                         invltlb();
  998 
  999                         tmp = *(int *)ptr;
 1000                         /*
 1001                          * Test for alternating 1's and 0's
 1002                          */
 1003                         *(volatile int *)ptr = 0xaaaaaaaa;
 1004                         if (*(volatile int *)ptr != 0xaaaaaaaa)
 1005                                 page_bad = TRUE;
 1006                         /*
 1007                          * Test for alternating 0's and 1's
 1008                          */
 1009                         *(volatile int *)ptr = 0x55555555;
 1010                         if (*(volatile int *)ptr != 0x55555555)
 1011                                 page_bad = TRUE;
 1012                         /*
 1013                          * Test for all 1's
 1014                          */
 1015                         *(volatile int *)ptr = 0xffffffff;
 1016                         if (*(volatile int *)ptr != 0xffffffff)
 1017                                 page_bad = TRUE;
 1018                         /*
 1019                          * Test for all 0's
 1020                          */
 1021                         *(volatile int *)ptr = 0x0;
 1022                         if (*(volatile int *)ptr != 0x0)
 1023                                 page_bad = TRUE;
 1024                         /*
 1025                          * Restore original value.
 1026                          */
 1027                         *(int *)ptr = tmp;
 1028 
 1029                         /*
 1030                          * Adjust array of valid/good pages.
 1031                          */
 1032                         if (page_bad == TRUE)
 1033                                 continue;
 1034                         /*
 1035                          * If this good page is a continuation of the
 1036                          * previous set of good pages, then just increase
 1037                          * the end pointer. Otherwise start a new chunk.
 1038                          * Note that "end" points one higher than end,
 1039                          * making the range >= start and < end.
 1040                          * If we're also doing a speculative memory
 1041                          * test and we at or past the end, bump up Maxmem
 1042                          * so that we keep going. The first bad page
 1043                          * will terminate the loop.
 1044                          */
 1045                         if (phys_avail[pa_indx] == pa) {
 1046                                 phys_avail[pa_indx] += PAGE_SIZE;
 1047                         } else {
 1048                                 pa_indx++;
 1049                                 if (pa_indx == PHYS_AVAIL_ARRAY_END) {
 1050                                         printf(
 1051                 "Too many holes in the physical address space, giving up\n");
 1052                                         pa_indx--;
 1053                                         break;
 1054                                 }
 1055                                 phys_avail[pa_indx++] = pa;     /* start */
 1056                                 phys_avail[pa_indx] = pa + PAGE_SIZE; /* end */
 1057                         }
 1058                         physmem++;
 1059                 }
 1060         }
 1061         *pte = 0;
 1062         invltlb();
 1063 
 1064         /*
 1065          * XXX
 1066          * The last chunk must contain at least one page plus the message
 1067          * buffer to avoid complicating other code (message buffer address
 1068          * calculation, etc.).
 1069          */
 1070         while (phys_avail[pa_indx - 1] + PAGE_SIZE +
 1071             round_page(MSGBUF_SIZE) >= phys_avail[pa_indx]) {
 1072                 physmem -= atop(phys_avail[pa_indx] - phys_avail[pa_indx - 1]);
 1073                 phys_avail[pa_indx--] = 0;
 1074                 phys_avail[pa_indx--] = 0;
 1075         }
 1076 
 1077         Maxmem = atop(phys_avail[pa_indx]);
 1078 
 1079         /* Trim off space for the message buffer. */
 1080         phys_avail[pa_indx] -= round_page(MSGBUF_SIZE);
 1081 
 1082         avail_end = phys_avail[pa_indx];
 1083 }
 1084 
 1085 u_int64_t
 1086 hammer_time(u_int64_t modulep, u_int64_t physfree)
 1087 {
 1088         caddr_t kmdp;
 1089         int gsel_tss, off, x;
 1090         struct pcpu *pc;
 1091         u_int64_t msr;
 1092         char *env;
 1093 
 1094 #ifdef DEV_ISA
 1095         /* Preemptively mask the atpics and leave them shut down */
 1096         outb(IO_ICU1 + ICU_IMR_OFFSET, 0xff);
 1097         outb(IO_ICU2 + ICU_IMR_OFFSET, 0xff);
 1098 #else
 1099 #error "have you forgotten the isa device?";
 1100 #endif
 1101 
 1102         proc0.p_uarea = (struct user *)(physfree + KERNBASE);
 1103         bzero(proc0.p_uarea, UAREA_PAGES * PAGE_SIZE);
 1104         physfree += UAREA_PAGES * PAGE_SIZE;
 1105         thread0.td_kstack = physfree + KERNBASE;
 1106         bzero((void *)thread0.td_kstack, KSTACK_PAGES * PAGE_SIZE);
 1107         physfree += KSTACK_PAGES * PAGE_SIZE;
 1108         thread0.td_pcb = (struct pcb *)
 1109            (thread0.td_kstack + KSTACK_PAGES * PAGE_SIZE) - 1;
 1110 
 1111         /*
 1112          * This may be done better later if it gets more high level
 1113          * components in it. If so just link td->td_proc here.
 1114          */
 1115         proc_linkup(&proc0, &ksegrp0, &thread0);
 1116 
 1117         preload_metadata = (caddr_t)(uintptr_t)(modulep + KERNBASE);
 1118         preload_bootstrap_relocate(KERNBASE);
 1119         kmdp = preload_search_by_type("elf kernel");
 1120         if (kmdp == NULL)
 1121                 kmdp = preload_search_by_type("elf64 kernel");
 1122         boothowto = MD_FETCH(kmdp, MODINFOMD_HOWTO, int);
 1123         kern_envp = MD_FETCH(kmdp, MODINFOMD_ENVP, char *) + KERNBASE;
 1124 #ifdef DDB
 1125         ksym_start = MD_FETCH(kmdp, MODINFOMD_SSYM, uintptr_t);
 1126         ksym_end = MD_FETCH(kmdp, MODINFOMD_ESYM, uintptr_t);
 1127 #endif
 1128 
 1129         /* Init basic tunables, hz etc */
 1130         init_param1();
 1131 
 1132         /*
 1133          * make gdt memory segments
 1134          */
 1135         gdt_segs[GPROC0_SEL].ssd_base = (uintptr_t)&common_tss[0];
 1136 
 1137         for (x = 0; x < NGDT; x++) {
 1138                 if (x != GPROC0_SEL && x != (GPROC0_SEL + 1))
 1139                         ssdtosd(&gdt_segs[x], &gdt[x]);
 1140         }
 1141         ssdtosyssd(&gdt_segs[GPROC0_SEL],
 1142             (struct system_segment_descriptor *)&gdt[GPROC0_SEL]);
 1143 
 1144         r_gdt.rd_limit = NGDT * sizeof(gdt[0]) - 1;
 1145         r_gdt.rd_base =  (long) gdt;
 1146         lgdt(&r_gdt);
 1147         pc = &__pcpu[0];
 1148 
 1149         wrmsr(MSR_FSBASE, 0);           /* User value */
 1150         wrmsr(MSR_GSBASE, (u_int64_t)pc);
 1151         wrmsr(MSR_KGSBASE, 0);          /* User value while in the kernel */
 1152 
 1153         pcpu_init(pc, 0, sizeof(struct pcpu));
 1154         PCPU_SET(prvspace, pc);
 1155         PCPU_SET(curthread, &thread0);
 1156         PCPU_SET(curpcb, thread0.td_pcb);
 1157         PCPU_SET(tssp, &common_tss[0]);
 1158 
 1159         /*
 1160          * Initialize mutexes.
 1161          *
 1162          * icu_lock: in order to allow an interrupt to occur in a critical
 1163          *           section, to set pcpu->ipending (etc...) properly, we
 1164          *           must be able to get the icu lock, so it can't be
 1165          *           under witness.
 1166          */
 1167         mutex_init();
 1168         mtx_init(&clock_lock, "clk", NULL, MTX_SPIN);
 1169         mtx_init(&icu_lock, "icu", NULL, MTX_SPIN | MTX_NOWITNESS);
 1170 
 1171         /* exceptions */
 1172         for (x = 0; x < NIDT; x++)
 1173                 setidt(x, &IDTVEC(rsvd), SDT_SYSIGT, SEL_KPL, 0);
 1174         setidt(IDT_DE, &IDTVEC(div),  SDT_SYSIGT, SEL_KPL, 0);
 1175         setidt(IDT_DB, &IDTVEC(dbg),  SDT_SYSIGT, SEL_KPL, 0);
 1176         setidt(IDT_NMI, &IDTVEC(nmi),  SDT_SYSIGT, SEL_KPL, 0);
 1177         setidt(IDT_BP, &IDTVEC(bpt),  SDT_SYSIGT, SEL_UPL, 0);
 1178         setidt(IDT_OF, &IDTVEC(ofl),  SDT_SYSIGT, SEL_KPL, 0);
 1179         setidt(IDT_BR, &IDTVEC(bnd),  SDT_SYSIGT, SEL_KPL, 0);
 1180         setidt(IDT_UD, &IDTVEC(ill),  SDT_SYSIGT, SEL_KPL, 0);
 1181         setidt(IDT_NM, &IDTVEC(dna),  SDT_SYSIGT, SEL_KPL, 0);
 1182         setidt(IDT_DF, &IDTVEC(dblfault), SDT_SYSIGT, SEL_KPL, 1);
 1183         setidt(IDT_FPUGP, &IDTVEC(fpusegm),  SDT_SYSIGT, SEL_KPL, 0);
 1184         setidt(IDT_TS, &IDTVEC(tss),  SDT_SYSIGT, SEL_KPL, 0);
 1185         setidt(IDT_NP, &IDTVEC(missing),  SDT_SYSIGT, SEL_KPL, 0);
 1186         setidt(IDT_SS, &IDTVEC(stk),  SDT_SYSIGT, SEL_KPL, 0);
 1187         setidt(IDT_GP, &IDTVEC(prot),  SDT_SYSIGT, SEL_KPL, 0);
 1188         setidt(IDT_PF, &IDTVEC(page),  SDT_SYSIGT, SEL_KPL, 0);
 1189         setidt(IDT_MF, &IDTVEC(fpu),  SDT_SYSIGT, SEL_KPL, 0);
 1190         setidt(IDT_AC, &IDTVEC(align), SDT_SYSIGT, SEL_KPL, 0);
 1191         setidt(IDT_MC, &IDTVEC(mchk),  SDT_SYSIGT, SEL_KPL, 0);
 1192         setidt(IDT_XF, &IDTVEC(xmm), SDT_SYSIGT, SEL_KPL, 0);
 1193 
 1194         r_idt.rd_limit = sizeof(idt0) - 1;
 1195         r_idt.rd_base = (long) idt;
 1196         lidt(&r_idt);
 1197 
 1198         /*
 1199          * Initialize the console before we print anything out.
 1200          */
 1201         cninit();
 1202 
 1203 #ifdef DEV_ATPIC
 1204         atpic_startup();
 1205 #endif
 1206 
 1207         kdb_init();
 1208 
 1209 #ifdef KDB
 1210         if (boothowto & RB_KDB)
 1211                 kdb_enter("Boot flags requested debugger");
 1212 #endif
 1213 
 1214         identify_cpu();         /* Final stage of CPU initialization */
 1215         initializecpu();        /* Initialize CPU registers */
 1216 
 1217         /* make an initial tss so cpu can get interrupt stack on syscall! */
 1218         common_tss[0].tss_rsp0 = thread0.td_kstack + \
 1219             KSTACK_PAGES * PAGE_SIZE - sizeof(struct pcb);
 1220         /* Ensure the stack is aligned to 16 bytes */
 1221         common_tss[0].tss_rsp0 &= ~0xFul;
 1222         PCPU_SET(rsp0, common_tss[0].tss_rsp0);
 1223 
 1224         /* doublefault stack space, runs on ist1 */
 1225         common_tss[0].tss_ist1 = (long)&dblfault_stack[sizeof(dblfault_stack)];
 1226 
 1227         /* Set the IO permission bitmap (empty due to tss seg limit) */
 1228         common_tss[0].tss_iobase = sizeof(struct amd64tss);
 1229 
 1230         gsel_tss = GSEL(GPROC0_SEL, SEL_KPL);
 1231         ltr(gsel_tss);
 1232 
 1233         /* Set up the fast syscall stuff */
 1234         msr = rdmsr(MSR_EFER) | EFER_SCE;
 1235         wrmsr(MSR_EFER, msr);
 1236         wrmsr(MSR_LSTAR, (u_int64_t)IDTVEC(fast_syscall));
 1237         wrmsr(MSR_CSTAR, (u_int64_t)IDTVEC(fast_syscall32));
 1238         msr = ((u_int64_t)GSEL(GCODE_SEL, SEL_KPL) << 32) |
 1239               ((u_int64_t)GSEL(GUCODE32_SEL, SEL_UPL) << 48);
 1240         wrmsr(MSR_STAR, msr);
 1241         wrmsr(MSR_SF_MASK, PSL_NT|PSL_T|PSL_I|PSL_C|PSL_D);
 1242 
 1243         getmemsize(kmdp, physfree);
 1244         init_param2(physmem);
 1245 
 1246         /* now running on new page tables, configured,and u/iom is accessible */
 1247 
 1248         /* Map the message buffer. */
 1249         for (off = 0; off < round_page(MSGBUF_SIZE); off += PAGE_SIZE)
 1250                 pmap_kenter((vm_offset_t)msgbufp + off, avail_end + off);
 1251 
 1252         msgbufinit(msgbufp, MSGBUF_SIZE);
 1253         fpuinit();
 1254 
 1255         /* transfer to user mode */
 1256 
 1257         _ucodesel = GSEL(GUCODE_SEL, SEL_UPL);
 1258         _udatasel = GSEL(GUDATA_SEL, SEL_UPL);
 1259         _ucode32sel = GSEL(GUCODE32_SEL, SEL_UPL);
 1260 
 1261         /* setup proc 0's pcb */
 1262         thread0.td_pcb->pcb_flags = 0; /* XXXKSE */
 1263         thread0.td_pcb->pcb_cr3 = KPML4phys;
 1264         thread0.td_frame = &proc0_tf;
 1265 
 1266         env = getenv("kernelname");
 1267         if (env != NULL)
 1268                 strlcpy(kernelname, env, sizeof(kernelname));
 1269 
 1270         /* Location of kernel stack for locore */
 1271         return ((u_int64_t)thread0.td_pcb);
 1272 }
 1273 
 1274 void
 1275 cpu_pcpu_init(struct pcpu *pcpu, int cpuid, size_t size)
 1276 {
 1277 
 1278         pcpu->pc_acpi_id = 0xffffffff;
 1279 }
 1280 
 1281 /*
 1282  * Construct a PCB from a trapframe. This is called from kdb_trap() where
 1283  * we want to start a backtrace from the function that caused us to enter
 1284  * the debugger. We have the context in the trapframe, but base the trace
 1285  * on the PCB. The PCB doesn't have to be perfect, as long as it contains
 1286  * enough for a backtrace.
 1287  */
 1288 void
 1289 makectx(struct trapframe *tf, struct pcb *pcb)
 1290 {
 1291 
 1292         pcb->pcb_r12 = tf->tf_r12;
 1293         pcb->pcb_r13 = tf->tf_r13;
 1294         pcb->pcb_r14 = tf->tf_r14;
 1295         pcb->pcb_r15 = tf->tf_r15;
 1296         pcb->pcb_rbp = tf->tf_rbp;
 1297         pcb->pcb_rbx = tf->tf_rbx;
 1298         pcb->pcb_rip = tf->tf_rip;
 1299         pcb->pcb_rsp = (ISPL(tf->tf_cs)) ? tf->tf_rsp : (long)(tf + 1) - 8;
 1300 }
 1301 
 1302 int
 1303 ptrace_set_pc(struct thread *td, unsigned long addr)
 1304 {
 1305         td->td_frame->tf_rip = addr;
 1306         return (0);
 1307 }
 1308 
 1309 int
 1310 ptrace_single_step(struct thread *td)
 1311 {
 1312         td->td_frame->tf_rflags |= PSL_T;
 1313         return (0);
 1314 }
 1315 
 1316 int
 1317 ptrace_clear_single_step(struct thread *td)
 1318 {
 1319         td->td_frame->tf_rflags &= ~PSL_T;
 1320         return (0);
 1321 }
 1322 
 1323 int
 1324 fill_regs(struct thread *td, struct reg *regs)
 1325 {
 1326         struct pcb *pcb;
 1327         struct trapframe *tp;
 1328 
 1329         tp = td->td_frame;
 1330         regs->r_r15 = tp->tf_r15;
 1331         regs->r_r14 = tp->tf_r14;
 1332         regs->r_r13 = tp->tf_r13;
 1333         regs->r_r12 = tp->tf_r12;
 1334         regs->r_r11 = tp->tf_r11;
 1335         regs->r_r10 = tp->tf_r10;
 1336         regs->r_r9  = tp->tf_r9;
 1337         regs->r_r8  = tp->tf_r8;
 1338         regs->r_rdi = tp->tf_rdi;
 1339         regs->r_rsi = tp->tf_rsi;
 1340         regs->r_rbp = tp->tf_rbp;
 1341         regs->r_rbx = tp->tf_rbx;
 1342         regs->r_rdx = tp->tf_rdx;
 1343         regs->r_rcx = tp->tf_rcx;
 1344         regs->r_rax = tp->tf_rax;
 1345         regs->r_rip = tp->tf_rip;
 1346         regs->r_cs = tp->tf_cs;
 1347         regs->r_rflags = tp->tf_rflags;
 1348         regs->r_rsp = tp->tf_rsp;
 1349         regs->r_ss = tp->tf_ss;
 1350         pcb = td->td_pcb;
 1351         return (0);
 1352 }
 1353 
 1354 int
 1355 set_regs(struct thread *td, struct reg *regs)
 1356 {
 1357         struct pcb *pcb;
 1358         struct trapframe *tp;
 1359         register_t rflags;
 1360 
 1361         tp = td->td_frame;
 1362         rflags = regs->r_rflags & 0xffffffff;
 1363         if (!EFL_SECURE(rflags, tp->tf_rflags) || !CS_SECURE(regs->r_cs))
 1364                 return (EINVAL);
 1365         tp->tf_r15 = regs->r_r15;
 1366         tp->tf_r14 = regs->r_r14;
 1367         tp->tf_r13 = regs->r_r13;
 1368         tp->tf_r12 = regs->r_r12;
 1369         tp->tf_r11 = regs->r_r11;
 1370         tp->tf_r10 = regs->r_r10;
 1371         tp->tf_r9  = regs->r_r9;
 1372         tp->tf_r8  = regs->r_r8;
 1373         tp->tf_rdi = regs->r_rdi;
 1374         tp->tf_rsi = regs->r_rsi;
 1375         tp->tf_rbp = regs->r_rbp;
 1376         tp->tf_rbx = regs->r_rbx;
 1377         tp->tf_rdx = regs->r_rdx;
 1378         tp->tf_rcx = regs->r_rcx;
 1379         tp->tf_rax = regs->r_rax;
 1380         tp->tf_rip = regs->r_rip;
 1381         tp->tf_cs = regs->r_cs;
 1382         tp->tf_rflags = rflags;
 1383         tp->tf_rsp = regs->r_rsp;
 1384         tp->tf_ss = regs->r_ss;
 1385         pcb = td->td_pcb;
 1386         return (0);
 1387 }
 1388 
 1389 /* XXX check all this stuff! */
 1390 /* externalize from sv_xmm */
 1391 static void
 1392 fill_fpregs_xmm(struct savefpu *sv_xmm, struct fpreg *fpregs)
 1393 {
 1394         struct envxmm *penv_fpreg = (struct envxmm *)&fpregs->fpr_env;
 1395         struct envxmm *penv_xmm = &sv_xmm->sv_env;
 1396         int i;
 1397 
 1398         /* pcb -> fpregs */
 1399         bzero(fpregs, sizeof(*fpregs));
 1400 
 1401         /* FPU control/status */
 1402         penv_fpreg->en_cw = penv_xmm->en_cw;
 1403         penv_fpreg->en_sw = penv_xmm->en_sw;
 1404         penv_fpreg->en_tw = penv_xmm->en_tw;
 1405         penv_fpreg->en_opcode = penv_xmm->en_opcode;
 1406         penv_fpreg->en_rip = penv_xmm->en_rip;
 1407         penv_fpreg->en_rdp = penv_xmm->en_rdp;
 1408         penv_fpreg->en_mxcsr = penv_xmm->en_mxcsr;
 1409         penv_fpreg->en_mxcsr_mask = penv_xmm->en_mxcsr_mask;
 1410 
 1411         /* FPU registers */
 1412         for (i = 0; i < 8; ++i)
 1413                 bcopy(sv_xmm->sv_fp[i].fp_acc.fp_bytes, fpregs->fpr_acc[i], 10);
 1414 
 1415         /* SSE registers */
 1416         for (i = 0; i < 16; ++i)
 1417                 bcopy(sv_xmm->sv_xmm[i].xmm_bytes, fpregs->fpr_xacc[i], 16);
 1418 }
 1419 
 1420 /* internalize from fpregs into sv_xmm */
 1421 static void
 1422 set_fpregs_xmm(struct fpreg *fpregs, struct savefpu *sv_xmm)
 1423 {
 1424         struct envxmm *penv_xmm = &sv_xmm->sv_env;
 1425         struct envxmm *penv_fpreg = (struct envxmm *)&fpregs->fpr_env;
 1426         int i;
 1427 
 1428         /* fpregs -> pcb */
 1429         /* FPU control/status */
 1430         penv_xmm->en_cw = penv_fpreg->en_cw;
 1431         penv_xmm->en_sw = penv_fpreg->en_sw;
 1432         penv_xmm->en_tw = penv_fpreg->en_tw;
 1433         penv_xmm->en_opcode = penv_fpreg->en_opcode;
 1434         penv_xmm->en_rip = penv_fpreg->en_rip;
 1435         penv_xmm->en_rdp = penv_fpreg->en_rdp;
 1436         penv_xmm->en_mxcsr = penv_fpreg->en_mxcsr;
 1437         penv_xmm->en_mxcsr_mask = penv_fpreg->en_mxcsr_mask;
 1438 
 1439         /* FPU registers */
 1440         for (i = 0; i < 8; ++i)
 1441                 bcopy(fpregs->fpr_acc[i], sv_xmm->sv_fp[i].fp_acc.fp_bytes, 10);
 1442 
 1443         /* SSE registers */
 1444         for (i = 0; i < 16; ++i)
 1445                 bcopy(fpregs->fpr_xacc[i], sv_xmm->sv_xmm[i].xmm_bytes, 16);
 1446 }
 1447 
 1448 /* externalize from td->pcb */
 1449 int
 1450 fill_fpregs(struct thread *td, struct fpreg *fpregs)
 1451 {
 1452 
 1453         fill_fpregs_xmm(&td->td_pcb->pcb_save, fpregs);
 1454         return (0);
 1455 }
 1456 
 1457 /* internalize to td->pcb */
 1458 int
 1459 set_fpregs(struct thread *td, struct fpreg *fpregs)
 1460 {
 1461 
 1462         set_fpregs_xmm(fpregs, &td->td_pcb->pcb_save);
 1463         return (0);
 1464 }
 1465 
 1466 /*
 1467  * Get machine context.
 1468  */
 1469 int
 1470 get_mcontext(struct thread *td, mcontext_t *mcp, int flags)
 1471 {
 1472         struct trapframe *tp;
 1473 
 1474         tp = td->td_frame;
 1475         PROC_LOCK(curthread->td_proc);
 1476         mcp->mc_onstack = sigonstack(tp->tf_rsp);
 1477         PROC_UNLOCK(curthread->td_proc);
 1478         mcp->mc_r15 = tp->tf_r15;
 1479         mcp->mc_r14 = tp->tf_r14;
 1480         mcp->mc_r13 = tp->tf_r13;
 1481         mcp->mc_r12 = tp->tf_r12;
 1482         mcp->mc_r11 = tp->tf_r11;
 1483         mcp->mc_r10 = tp->tf_r10;
 1484         mcp->mc_r9  = tp->tf_r9;
 1485         mcp->mc_r8  = tp->tf_r8;
 1486         mcp->mc_rdi = tp->tf_rdi;
 1487         mcp->mc_rsi = tp->tf_rsi;
 1488         mcp->mc_rbp = tp->tf_rbp;
 1489         mcp->mc_rbx = tp->tf_rbx;
 1490         mcp->mc_rcx = tp->tf_rcx;
 1491         if (flags & GET_MC_CLEAR_RET) {
 1492                 mcp->mc_rax = 0;
 1493                 mcp->mc_rdx = 0;
 1494         } else {
 1495                 mcp->mc_rax = tp->tf_rax;
 1496                 mcp->mc_rdx = tp->tf_rdx;
 1497         }
 1498         mcp->mc_rip = tp->tf_rip;
 1499         mcp->mc_cs = tp->tf_cs;
 1500         mcp->mc_rflags = tp->tf_rflags;
 1501         mcp->mc_rsp = tp->tf_rsp;
 1502         mcp->mc_ss = tp->tf_ss;
 1503         mcp->mc_len = sizeof(*mcp);
 1504         get_fpcontext(td, mcp);
 1505         return (0);
 1506 }
 1507 
 1508 /*
 1509  * Set machine context.
 1510  *
 1511  * However, we don't set any but the user modifiable flags, and we won't
 1512  * touch the cs selector.
 1513  */
 1514 int
 1515 set_mcontext(struct thread *td, const mcontext_t *mcp)
 1516 {
 1517         struct trapframe *tp;
 1518         long rflags;
 1519         int ret;
 1520 
 1521         tp = td->td_frame;
 1522         if (mcp->mc_len != sizeof(*mcp))
 1523                 return (EINVAL);
 1524         rflags = (mcp->mc_rflags & PSL_USERCHANGE) |
 1525             (tp->tf_rflags & ~PSL_USERCHANGE);
 1526         ret = set_fpcontext(td, mcp);
 1527         if (ret != 0)
 1528                 return (ret);
 1529         tp->tf_r15 = mcp->mc_r15;
 1530         tp->tf_r14 = mcp->mc_r14;
 1531         tp->tf_r13 = mcp->mc_r13;
 1532         tp->tf_r12 = mcp->mc_r12;
 1533         tp->tf_r11 = mcp->mc_r11;
 1534         tp->tf_r10 = mcp->mc_r10;
 1535         tp->tf_r9  = mcp->mc_r9;
 1536         tp->tf_r8  = mcp->mc_r8;
 1537         tp->tf_rdi = mcp->mc_rdi;
 1538         tp->tf_rsi = mcp->mc_rsi;
 1539         tp->tf_rbp = mcp->mc_rbp;
 1540         tp->tf_rbx = mcp->mc_rbx;
 1541         tp->tf_rdx = mcp->mc_rdx;
 1542         tp->tf_rcx = mcp->mc_rcx;
 1543         tp->tf_rax = mcp->mc_rax;
 1544         tp->tf_rip = mcp->mc_rip;
 1545         tp->tf_rflags = rflags;
 1546         tp->tf_rsp = mcp->mc_rsp;
 1547         tp->tf_ss = mcp->mc_ss;
 1548         td->td_pcb->pcb_flags |= PCB_FULLCTX;
 1549         return (0);
 1550 }
 1551 
 1552 static void
 1553 get_fpcontext(struct thread *td, mcontext_t *mcp)
 1554 {
 1555 
 1556         mcp->mc_ownedfp = fpugetregs(td, (struct savefpu *)&mcp->mc_fpstate);
 1557         mcp->mc_fpformat = fpuformat();
 1558 }
 1559 
 1560 static int
 1561 set_fpcontext(struct thread *td, const mcontext_t *mcp)
 1562 {
 1563 
 1564         if (mcp->mc_fpformat == _MC_FPFMT_NODEV)
 1565                 return (0);
 1566         else if (mcp->mc_fpformat != _MC_FPFMT_XMM)
 1567                 return (EINVAL);
 1568         else if (mcp->mc_ownedfp == _MC_FPOWNED_NONE)
 1569                 /* We don't care what state is left in the FPU or PCB. */
 1570                 fpstate_drop(td);
 1571         else if (mcp->mc_ownedfp == _MC_FPOWNED_FPU ||
 1572             mcp->mc_ownedfp == _MC_FPOWNED_PCB) {
 1573                 /*
 1574                  * XXX we violate the dubious requirement that fpusetregs()
 1575                  * be called with interrupts disabled.
 1576                  * XXX obsolete on trap-16 systems?
 1577                  */
 1578                 fpusetregs(td, (struct savefpu *)&mcp->mc_fpstate);
 1579         } else
 1580                 return (EINVAL);
 1581         return (0);
 1582 }
 1583 
 1584 void
 1585 fpstate_drop(struct thread *td)
 1586 {
 1587         register_t s;
 1588 
 1589         s = intr_disable();
 1590         if (PCPU_GET(fpcurthread) == td)
 1591                 fpudrop();
 1592         /*
 1593          * XXX force a full drop of the fpu.  The above only drops it if we
 1594          * owned it.
 1595          *
 1596          * XXX I don't much like fpugetregs()'s semantics of doing a full
 1597          * drop.  Dropping only to the pcb matches fnsave's behaviour.
 1598          * We only need to drop to !PCB_INITDONE in sendsig().  But
 1599          * sendsig() is the only caller of fpugetregs()... perhaps we just
 1600          * have too many layers.
 1601          */
 1602         curthread->td_pcb->pcb_flags &= ~PCB_FPUINITDONE;
 1603         intr_restore(s);
 1604 }
 1605 
 1606 int
 1607 fill_dbregs(struct thread *td, struct dbreg *dbregs)
 1608 {
 1609         struct pcb *pcb;
 1610 
 1611         if (td == NULL) {
 1612                 dbregs->dr[0] = rdr0();
 1613                 dbregs->dr[1] = rdr1();
 1614                 dbregs->dr[2] = rdr2();
 1615                 dbregs->dr[3] = rdr3();
 1616                 dbregs->dr[6] = rdr6();
 1617                 dbregs->dr[7] = rdr7();
 1618         } else {
 1619                 pcb = td->td_pcb;
 1620                 dbregs->dr[0] = pcb->pcb_dr0;
 1621                 dbregs->dr[1] = pcb->pcb_dr1;
 1622                 dbregs->dr[2] = pcb->pcb_dr2;
 1623                 dbregs->dr[3] = pcb->pcb_dr3;
 1624                 dbregs->dr[6] = pcb->pcb_dr6;
 1625                 dbregs->dr[7] = pcb->pcb_dr7;
 1626         }
 1627         dbregs->dr[4] = 0;
 1628         dbregs->dr[5] = 0;
 1629         dbregs->dr[8] = 0;
 1630         dbregs->dr[9] = 0;
 1631         dbregs->dr[10] = 0;
 1632         dbregs->dr[11] = 0;
 1633         dbregs->dr[12] = 0;
 1634         dbregs->dr[13] = 0;
 1635         dbregs->dr[14] = 0;
 1636         dbregs->dr[15] = 0;
 1637         return (0);
 1638 }
 1639 
 1640 int
 1641 set_dbregs(struct thread *td, struct dbreg *dbregs)
 1642 {
 1643         struct pcb *pcb;
 1644         int i;
 1645         u_int64_t mask1, mask2;
 1646 
 1647         if (td == NULL) {
 1648                 load_dr0(dbregs->dr[0]);
 1649                 load_dr1(dbregs->dr[1]);
 1650                 load_dr2(dbregs->dr[2]);
 1651                 load_dr3(dbregs->dr[3]);
 1652                 load_dr6(dbregs->dr[6]);
 1653                 load_dr7(dbregs->dr[7]);
 1654         } else {
 1655                 /*
 1656                  * Don't let an illegal value for dr7 get set.  Specifically,
 1657                  * check for undefined settings.  Setting these bit patterns
 1658                  * result in undefined behaviour and can lead to an unexpected
 1659                  * TRCTRAP or a general protection fault right here.
 1660                  */
 1661                 for (i = 0, mask1 = 0x3<<16, mask2 = 0x2<<16; i < 8;
 1662                      i++, mask1 <<= 2, mask2 <<= 2)
 1663                         if ((dbregs->dr[7] & mask1) == mask2)
 1664                                 return (EINVAL);
 1665 
 1666                 pcb = td->td_pcb;
 1667 
 1668                 /*
 1669                  * Don't let a process set a breakpoint that is not within the
 1670                  * process's address space.  If a process could do this, it
 1671                  * could halt the system by setting a breakpoint in the kernel
 1672                  * (if ddb was enabled).  Thus, we need to check to make sure
 1673                  * that no breakpoints are being enabled for addresses outside
 1674                  * process's address space, unless, perhaps, we were called by
 1675                  * uid 0.
 1676                  *
 1677                  * XXX - what about when the watched area of the user's
 1678                  * address space is written into from within the kernel
 1679                  * ... wouldn't that still cause a breakpoint to be generated
 1680                  * from within kernel mode?
 1681                  */
 1682 
 1683                 if (suser(td) != 0) {
 1684                         if (dbregs->dr[7] & 0x3) {
 1685                                 /* dr0 is enabled */
 1686                                 if (dbregs->dr[0] >= VM_MAXUSER_ADDRESS)
 1687                                         return (EINVAL);
 1688                         }
 1689                         if (dbregs->dr[7] & 0x3<<2) {
 1690                                 /* dr1 is enabled */
 1691                                 if (dbregs->dr[1] >= VM_MAXUSER_ADDRESS)
 1692                                         return (EINVAL);
 1693                         }
 1694                         if (dbregs->dr[7] & 0x3<<4) {
 1695                                 /* dr2 is enabled */
 1696                                 if (dbregs->dr[2] >= VM_MAXUSER_ADDRESS)
 1697                                         return (EINVAL);
 1698                         }
 1699                         if (dbregs->dr[7] & 0x3<<6) {
 1700                                 /* dr3 is enabled */
 1701                                 if (dbregs->dr[3] >= VM_MAXUSER_ADDRESS)
 1702                                         return (EINVAL);
 1703                         }
 1704                 }
 1705 
 1706                 pcb->pcb_dr0 = dbregs->dr[0];
 1707                 pcb->pcb_dr1 = dbregs->dr[1];
 1708                 pcb->pcb_dr2 = dbregs->dr[2];
 1709                 pcb->pcb_dr3 = dbregs->dr[3];
 1710                 pcb->pcb_dr6 = dbregs->dr[6];
 1711                 pcb->pcb_dr7 = dbregs->dr[7];
 1712 
 1713                 pcb->pcb_flags |= PCB_DBREGS;
 1714         }
 1715 
 1716         return (0);
 1717 }
 1718 
 1719 void
 1720 reset_dbregs(void)
 1721 {
 1722 
 1723         load_dr7(0);    /* Turn off the control bits first */
 1724         load_dr0(0);
 1725         load_dr1(0);
 1726         load_dr2(0);
 1727         load_dr3(0);
 1728         load_dr6(0);
 1729 }
 1730 
 1731 /*
 1732  * Return > 0 if a hardware breakpoint has been hit, and the
 1733  * breakpoint was in user space.  Return 0, otherwise.
 1734  */
 1735 int
 1736 user_dbreg_trap(void)
 1737 {
 1738         u_int64_t dr7, dr6; /* debug registers dr6 and dr7 */
 1739         u_int64_t bp;       /* breakpoint bits extracted from dr6 */
 1740         int nbp;            /* number of breakpoints that triggered */
 1741         caddr_t addr[4];    /* breakpoint addresses */
 1742         int i;
 1743         
 1744         dr7 = rdr7();
 1745         if ((dr7 & 0x000000ff) == 0) {
 1746                 /*
 1747                  * all GE and LE bits in the dr7 register are zero,
 1748                  * thus the trap couldn't have been caused by the
 1749                  * hardware debug registers
 1750                  */
 1751                 return 0;
 1752         }
 1753 
 1754         nbp = 0;
 1755         dr6 = rdr6();
 1756         bp = dr6 & 0x0000000f;
 1757 
 1758         if (!bp) {
 1759                 /*
 1760                  * None of the breakpoint bits are set meaning this
 1761                  * trap was not caused by any of the debug registers
 1762                  */
 1763                 return 0;
 1764         }
 1765 
 1766         /*
 1767          * at least one of the breakpoints were hit, check to see
 1768          * which ones and if any of them are user space addresses
 1769          */
 1770 
 1771         if (bp & 0x01) {
 1772                 addr[nbp++] = (caddr_t)rdr0();
 1773         }
 1774         if (bp & 0x02) {
 1775                 addr[nbp++] = (caddr_t)rdr1();
 1776         }
 1777         if (bp & 0x04) {
 1778                 addr[nbp++] = (caddr_t)rdr2();
 1779         }
 1780         if (bp & 0x08) {
 1781                 addr[nbp++] = (caddr_t)rdr3();
 1782         }
 1783 
 1784         for (i=0; i<nbp; i++) {
 1785                 if (addr[i] <
 1786                     (caddr_t)VM_MAXUSER_ADDRESS) {
 1787                         /*
 1788                          * addr[i] is in user space
 1789                          */
 1790                         return nbp;
 1791                 }
 1792         }
 1793 
 1794         /*
 1795          * None of the breakpoints are in user space.
 1796          */
 1797         return 0;
 1798 }
 1799 
 1800 #ifdef KDB
 1801 
 1802 /*
 1803  * Provide inb() and outb() as functions.  They are normally only
 1804  * available as macros calling inlined functions, thus cannot be
 1805  * called from the debugger.
 1806  *
 1807  * The actual code is stolen from <machine/cpufunc.h>, and de-inlined.
 1808  */
 1809 
 1810 #undef inb
 1811 #undef outb
 1812 
 1813 /* silence compiler warnings */
 1814 u_char inb(u_int);
 1815 void outb(u_int, u_char);
 1816 
 1817 u_char
 1818 inb(u_int port)
 1819 {
 1820         u_char  data;
 1821         /*
 1822          * We use %%dx and not %1 here because i/o is done at %dx and not at
 1823          * %edx, while gcc generates inferior code (movw instead of movl)
 1824          * if we tell it to load (u_short) port.
 1825          */
 1826         __asm __volatile("inb %%dx,%0" : "=a" (data) : "d" (port));
 1827         return (data);
 1828 }
 1829 
 1830 void
 1831 outb(u_int port, u_char data)
 1832 {
 1833         u_char  al;
 1834         /*
 1835          * Use an unnecessary assignment to help gcc's register allocator.
 1836          * This make a large difference for gcc-1.40 and a tiny difference
 1837          * for gcc-2.6.0.  For gcc-1.40, al had to be ``asm("ax")'' for
 1838          * best results.  gcc-2.6.0 can't handle this.
 1839          */
 1840         al = data;
 1841         __asm __volatile("outb %0,%%dx" : : "a" (al), "d" (port));
 1842 }
 1843 
 1844 #endif /* KDB */

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