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("$FreeBSD$");
   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/proc.h>
   59 #include <sys/systm.h>
   60 #include <sys/bio.h>
   61 #include <sys/buf.h>
   62 #include <sys/bus.h>
   63 #include <sys/callout.h>
   64 #include <sys/clock.h>
   65 #include <sys/cons.h>
   66 #include <sys/cpu.h>
   67 #include <sys/eventhandler.h>
   68 #include <sys/exec.h>
   69 #include <sys/imgact.h>
   70 #include <sys/kdb.h>
   71 #include <sys/kernel.h>
   72 #include <sys/ktr.h>
   73 #include <sys/linker.h>
   74 #include <sys/lock.h>
   75 #include <sys/malloc.h>
   76 #include <sys/memrange.h>
   77 #include <sys/msgbuf.h>
   78 #include <sys/mutex.h>
   79 #include <sys/pcpu.h>
   80 #include <sys/ptrace.h>
   81 #include <sys/reboot.h>
   82 #include <sys/sched.h>
   83 #include <sys/signalvar.h>
   84 #include <sys/sysctl.h>
   85 #include <sys/sysent.h>
   86 #include <sys/sysproto.h>
   87 #include <sys/ucontext.h>
   88 #include <sys/vmmeter.h>
   89 
   90 #include <vm/vm.h>
   91 #include <vm/vm_extern.h>
   92 #include <vm/vm_kern.h>
   93 #include <vm/vm_page.h>
   94 #include <vm/vm_map.h>
   95 #include <vm/vm_object.h>
   96 #include <vm/vm_pager.h>
   97 #include <vm/vm_param.h>
   98 
   99 #ifdef DDB
  100 #ifndef KDB
  101 #error KDB must be enabled in order for DDB to work!
  102 #endif
  103 #endif
  104 #include <ddb/ddb.h>
  105 
  106 #include <net/netisr.h>
  107 
  108 #include <machine/clock.h>
  109 #include <machine/cpu.h>
  110 #include <machine/cputypes.h>
  111 #include <machine/intr_machdep.h>
  112 #include <machine/md_var.h>
  113 #include <machine/metadata.h>
  114 #include <machine/pc/bios.h>
  115 #include <machine/pcb.h>
  116 #include <machine/proc.h>
  117 #include <machine/reg.h>
  118 #include <machine/sigframe.h>
  119 #include <machine/specialreg.h>
  120 #ifdef PERFMON
  121 #include <machine/perfmon.h>
  122 #endif
  123 #include <machine/tss.h>
  124 #ifdef SMP
  125 #include <machine/smp.h>
  126 #endif
  127 
  128 #ifdef DEV_ATPIC
  129 #include <amd64/isa/icu.h>
  130 #else
  131 #include <machine/apicvar.h>
  132 #endif
  133 
  134 #include <isa/isareg.h>
  135 #include <isa/rtc.h>
  136 
  137 /* Sanity check for __curthread() */
  138 CTASSERT(offsetof(struct pcpu, pc_curthread) == 0);
  139 
  140 extern u_int64_t hammer_time(u_int64_t, u_int64_t);
  141 
  142 extern void printcpuinfo(void); /* XXX header file */
  143 extern void identify_cpu(void);
  144 extern void panicifcpuunsupported(void);
  145 
  146 #define CS_SECURE(cs)           (ISPL(cs) == SEL_UPL)
  147 #define EFL_SECURE(ef, oef)     ((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0)
  148 
  149 static void cpu_startup(void *);
  150 static void get_fpcontext(struct thread *td, mcontext_t *mcp);
  151 static int  set_fpcontext(struct thread *td, const mcontext_t *mcp);
  152 SYSINIT(cpu, SI_SUB_CPU, SI_ORDER_FIRST, cpu_startup, NULL);
  153 
  154 #ifdef DDB
  155 extern vm_offset_t ksym_start, ksym_end;
  156 #endif
  157 
  158 /* Intel ICH registers */
  159 #define ICH_PMBASE      0x400
  160 #define ICH_SMI_EN      ICH_PMBASE + 0x30
  161 
  162 int     _udatasel, _ucodesel, _ucode32sel;
  163 
  164 int cold = 1;
  165 
  166 long Maxmem = 0;
  167 long realmem = 0;
  168 
  169 /*
  170  * The number of PHYSMAP entries must be one less than the number of
  171  * PHYSSEG entries because the PHYSMAP entry that spans the largest
  172  * physical address that is accessible by ISA DMA is split into two
  173  * PHYSSEG entries.
  174  */
  175 #define PHYSMAP_SIZE    (2 * (VM_PHYSSEG_MAX - 1))
  176 
  177 vm_paddr_t phys_avail[PHYSMAP_SIZE + 2];
  178 vm_paddr_t dump_avail[PHYSMAP_SIZE + 2];
  179 
  180 /* must be 2 less so 0 0 can signal end of chunks */
  181 #define PHYS_AVAIL_ARRAY_END ((sizeof(phys_avail) / sizeof(phys_avail[0])) - 2)
  182 #define DUMP_AVAIL_ARRAY_END ((sizeof(dump_avail) / sizeof(dump_avail[0])) - 2)
  183 
  184 struct kva_md_info kmi;
  185 
  186 static struct trapframe proc0_tf;
  187 struct region_descriptor r_gdt, r_idt;
  188 
  189 struct pcpu __pcpu[MAXCPU];
  190 
  191 struct mtx icu_lock;
  192 
  193 struct mem_range_softc mem_range_softc;
  194 
  195 static void
  196 cpu_startup(dummy)
  197         void *dummy;
  198 {
  199         char *sysenv;
  200 
  201         /*
  202          * On MacBooks, we need to disallow the legacy USB circuit to
  203          * generate an SMI# because this can cause several problems,
  204          * namely: incorrect CPU frequency detection and failure to
  205          * start the APs.
  206          * We do this by disabling a bit in the SMI_EN (SMI Control and
  207          * Enable register) of the Intel ICH LPC Interface Bridge. 
  208          */
  209         sysenv = getenv("smbios.system.product");
  210         if (sysenv != NULL) {
  211                 if (strncmp(sysenv, "MacBook", 7) == 0) {
  212                         if (bootverbose)
  213                                 printf("Disabling LEGACY_USB_EN bit on "
  214                                     "Intel ICH.\n");
  215                         outl(ICH_SMI_EN, inl(ICH_SMI_EN) & ~0x8);
  216                 }
  217                 freeenv(sysenv);
  218         }
  219 
  220         /*
  221          * Good {morning,afternoon,evening,night}.
  222          */
  223         startrtclock();
  224         printcpuinfo();
  225         panicifcpuunsupported();
  226 #ifdef PERFMON
  227         perfmon_init();
  228 #endif
  229         printf("usable memory = %ju (%ju MB)\n", ptoa((uintmax_t)physmem),
  230             ptoa((uintmax_t)physmem) / 1048576);
  231         realmem = Maxmem;
  232         /*
  233          * Display any holes after the first chunk of extended memory.
  234          */
  235         if (bootverbose) {
  236                 int indx;
  237 
  238                 printf("Physical memory chunk(s):\n");
  239                 for (indx = 0; phys_avail[indx + 1] != 0; indx += 2) {
  240                         vm_paddr_t size;
  241 
  242                         size = phys_avail[indx + 1] - phys_avail[indx];
  243                         printf(
  244                             "0x%016jx - 0x%016jx, %ju bytes (%ju pages)\n",
  245                             (uintmax_t)phys_avail[indx],
  246                             (uintmax_t)phys_avail[indx + 1] - 1,
  247                             (uintmax_t)size, (uintmax_t)size / PAGE_SIZE);
  248                 }
  249         }
  250 
  251         vm_ksubmap_init(&kmi);
  252 
  253         printf("avail memory  = %ju (%ju MB)\n",
  254             ptoa((uintmax_t)cnt.v_free_count),
  255             ptoa((uintmax_t)cnt.v_free_count) / 1048576);
  256 
  257         /*
  258          * Set up buffers, so they can be used to read disk labels.
  259          */
  260         bufinit();
  261         vm_pager_bufferinit();
  262 
  263         cpu_setregs();
  264 }
  265 
  266 /*
  267  * Send an interrupt to process.
  268  *
  269  * Stack is set up to allow sigcode stored
  270  * at top to call routine, followed by kcall
  271  * to sigreturn routine below.  After sigreturn
  272  * resets the signal mask, the stack, and the
  273  * frame pointer, it returns to the user
  274  * specified pc, psl.
  275  */
  276 void
  277 sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask)
  278 {
  279         struct sigframe sf, *sfp;
  280         struct proc *p;
  281         struct thread *td;
  282         struct sigacts *psp;
  283         char *sp;
  284         struct trapframe *regs;
  285         int sig;
  286         int oonstack;
  287 
  288         td = curthread;
  289         p = td->td_proc;
  290         PROC_LOCK_ASSERT(p, MA_OWNED);
  291         sig = ksi->ksi_signo;
  292         psp = p->p_sigacts;
  293         mtx_assert(&psp->ps_mtx, MA_OWNED);
  294         regs = td->td_frame;
  295         oonstack = sigonstack(regs->tf_rsp);
  296 
  297         /* Save user context. */
  298         bzero(&sf, sizeof(sf));
  299         sf.sf_uc.uc_sigmask = *mask;
  300         sf.sf_uc.uc_stack = td->td_sigstk;
  301         sf.sf_uc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK)
  302             ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
  303         sf.sf_uc.uc_mcontext.mc_onstack = (oonstack) ? 1 : 0;
  304         bcopy(regs, &sf.sf_uc.uc_mcontext.mc_rdi, sizeof(*regs));
  305         sf.sf_uc.uc_mcontext.mc_len = sizeof(sf.sf_uc.uc_mcontext); /* magic */
  306         get_fpcontext(td, &sf.sf_uc.uc_mcontext);
  307         fpstate_drop(td);
  308 
  309         /* Allocate space for the signal handler context. */
  310         if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack &&
  311             SIGISMEMBER(psp->ps_sigonstack, sig)) {
  312                 sp = td->td_sigstk.ss_sp +
  313                     td->td_sigstk.ss_size - sizeof(struct sigframe);
  314 #if defined(COMPAT_43)
  315                 td->td_sigstk.ss_flags |= SS_ONSTACK;
  316 #endif
  317         } else
  318                 sp = (char *)regs->tf_rsp - sizeof(struct sigframe) - 128;
  319         /* Align to 16 bytes. */
  320         sfp = (struct sigframe *)((unsigned long)sp & ~0xFul);
  321 
  322         /* Translate the signal if appropriate. */
  323         if (p->p_sysent->sv_sigtbl && sig <= p->p_sysent->sv_sigsize)
  324                 sig = p->p_sysent->sv_sigtbl[_SIG_IDX(sig)];
  325 
  326         /* Build the argument list for the signal handler. */
  327         regs->tf_rdi = sig;                     /* arg 1 in %rdi */
  328         regs->tf_rdx = (register_t)&sfp->sf_uc; /* arg 3 in %rdx */
  329         if (SIGISMEMBER(psp->ps_siginfo, sig)) {
  330                 /* Signal handler installed with SA_SIGINFO. */
  331                 regs->tf_rsi = (register_t)&sfp->sf_si; /* arg 2 in %rsi */
  332                 sf.sf_ahu.sf_action = (__siginfohandler_t *)catcher;
  333 
  334                 /* Fill in POSIX parts */
  335                 sf.sf_si = ksi->ksi_info;
  336                 sf.sf_si.si_signo = sig; /* maybe a translated signal */
  337                 regs->tf_rcx = (register_t)ksi->ksi_addr; /* arg 4 in %rcx */
  338         } else {
  339                 /* Old FreeBSD-style arguments. */
  340                 regs->tf_rsi = ksi->ksi_code;   /* arg 2 in %rsi */
  341                 regs->tf_rcx = (register_t)ksi->ksi_addr; /* arg 4 in %rcx */
  342                 sf.sf_ahu.sf_handler = catcher;
  343         }
  344         mtx_unlock(&psp->ps_mtx);
  345         PROC_UNLOCK(p);
  346 
  347         /*
  348          * Copy the sigframe out to the user's stack.
  349          */
  350         if (copyout(&sf, sfp, sizeof(*sfp)) != 0) {
  351 #ifdef DEBUG
  352                 printf("process %ld has trashed its stack\n", (long)p->p_pid);
  353 #endif
  354                 PROC_LOCK(p);
  355                 sigexit(td, SIGILL);
  356         }
  357 
  358         regs->tf_rsp = (long)sfp;
  359         regs->tf_rip = PS_STRINGS - *(p->p_sysent->sv_szsigcode);
  360         regs->tf_rflags &= ~(PSL_T | PSL_D);
  361         regs->tf_cs = _ucodesel;
  362         PROC_LOCK(p);
  363         mtx_lock(&psp->ps_mtx);
  364 }
  365 
  366 /*
  367  * System call to cleanup state after a signal
  368  * has been taken.  Reset signal mask and
  369  * stack state from context left by sendsig (above).
  370  * Return to previous pc and psl as specified by
  371  * context left by sendsig. Check carefully to
  372  * make sure that the user has not modified the
  373  * state to gain improper privileges.
  374  *
  375  * MPSAFE
  376  */
  377 int
  378 sigreturn(td, uap)
  379         struct thread *td;
  380         struct sigreturn_args /* {
  381                 const struct __ucontext *sigcntxp;
  382         } */ *uap;
  383 {
  384         ucontext_t uc;
  385         struct proc *p = td->td_proc;
  386         struct trapframe *regs;
  387         const ucontext_t *ucp;
  388         long rflags;
  389         int cs, error, ret;
  390         ksiginfo_t ksi;
  391 
  392         error = copyin(uap->sigcntxp, &uc, sizeof(uc));
  393         if (error != 0)
  394                 return (error);
  395         ucp = &uc;
  396         regs = td->td_frame;
  397         rflags = ucp->uc_mcontext.mc_rflags;
  398         /*
  399          * Don't allow users to change privileged or reserved flags.
  400          */
  401         /*
  402          * XXX do allow users to change the privileged flag PSL_RF.
  403          * The cpu sets PSL_RF in tf_rflags for faults.  Debuggers
  404          * should sometimes set it there too.  tf_rflags is kept in
  405          * the signal context during signal handling and there is no
  406          * other place to remember it, so the PSL_RF bit may be
  407          * corrupted by the signal handler without us knowing.
  408          * Corruption of the PSL_RF bit at worst causes one more or
  409          * one less debugger trap, so allowing it is fairly harmless.
  410          */
  411         if (!EFL_SECURE(rflags & ~PSL_RF, regs->tf_rflags & ~PSL_RF)) {
  412                 printf("sigreturn: rflags = 0x%lx\n", rflags);
  413                 return (EINVAL);
  414         }
  415 
  416         /*
  417          * Don't allow users to load a valid privileged %cs.  Let the
  418          * hardware check for invalid selectors, excess privilege in
  419          * other selectors, invalid %eip's and invalid %esp's.
  420          */
  421         cs = ucp->uc_mcontext.mc_cs;
  422         if (!CS_SECURE(cs)) {
  423                 printf("sigreturn: cs = 0x%x\n", cs);
  424                 ksiginfo_init_trap(&ksi);
  425                 ksi.ksi_signo = SIGBUS;
  426                 ksi.ksi_code = BUS_OBJERR;
  427                 ksi.ksi_trapno = T_PROTFLT;
  428                 ksi.ksi_addr = (void *)regs->tf_rip;
  429                 trapsignal(td, &ksi);
  430                 return (EINVAL);
  431         }
  432 
  433         ret = set_fpcontext(td, &ucp->uc_mcontext);
  434         if (ret != 0)
  435                 return (ret);
  436         bcopy(&ucp->uc_mcontext.mc_rdi, regs, sizeof(*regs));
  437 
  438         PROC_LOCK(p);
  439 #if defined(COMPAT_43)
  440         if (ucp->uc_mcontext.mc_onstack & 1)
  441                 td->td_sigstk.ss_flags |= SS_ONSTACK;
  442         else
  443                 td->td_sigstk.ss_flags &= ~SS_ONSTACK;
  444 #endif
  445 
  446         td->td_sigmask = ucp->uc_sigmask;
  447         SIG_CANTMASK(td->td_sigmask);
  448         signotify(td);
  449         PROC_UNLOCK(p);
  450         td->td_pcb->pcb_flags |= PCB_FULLCTX;
  451         return (EJUSTRETURN);
  452 }
  453 
  454 #ifdef COMPAT_FREEBSD4
  455 int
  456 freebsd4_sigreturn(struct thread *td, struct freebsd4_sigreturn_args *uap)
  457 {
  458  
  459         return sigreturn(td, (struct sigreturn_args *)uap);
  460 }
  461 #endif
  462 
  463 
  464 /*
  465  * Machine dependent boot() routine
  466  *
  467  * I haven't seen anything to put here yet
  468  * Possibly some stuff might be grafted back here from boot()
  469  */
  470 void
  471 cpu_boot(int howto)
  472 {
  473 }
  474 
  475 /* Get current clock frequency for the given cpu id. */
  476 int
  477 cpu_est_clockrate(int cpu_id, uint64_t *rate)
  478 {
  479         register_t reg;
  480         uint64_t tsc1, tsc2;
  481 
  482         if (pcpu_find(cpu_id) == NULL || rate == NULL)
  483                 return (EINVAL);
  484 
  485         /* If we're booting, trust the rate calibrated moments ago. */
  486         if (cold) {
  487                 *rate = tsc_freq;
  488                 return (0);
  489         }
  490 
  491 #ifdef SMP
  492         /* Schedule ourselves on the indicated cpu. */
  493         thread_lock(curthread);
  494         sched_bind(curthread, cpu_id);
  495         thread_unlock(curthread);
  496 #endif
  497 
  498         /* Calibrate by measuring a short delay. */
  499         reg = intr_disable();
  500         tsc1 = rdtsc();
  501         DELAY(1000);
  502         tsc2 = rdtsc();
  503         intr_restore(reg);
  504 
  505 #ifdef SMP
  506         thread_lock(curthread);
  507         sched_unbind(curthread);
  508         thread_unlock(curthread);
  509 #endif
  510 
  511         /*
  512          * Calculate the difference in readings, convert to Mhz, and
  513          * subtract 0.5% of the total.  Empirical testing has shown that
  514          * overhead in DELAY() works out to approximately this value.
  515          */
  516         tsc2 -= tsc1;
  517         *rate = tsc2 * 1000 - tsc2 * 5;
  518         return (0);
  519 }
  520 
  521 /*
  522  * Shutdown the CPU as much as possible
  523  */
  524 void
  525 cpu_halt(void)
  526 {
  527         for (;;)
  528                 __asm__ ("hlt");
  529 }
  530 
  531 /*
  532  * Hook to idle the CPU when possible.  In the SMP case we default to
  533  * off because a halted cpu will not currently pick up a new thread in the
  534  * run queue until the next timer tick.  If turned on this will result in
  535  * approximately a 4.2% loss in real time performance in buildworld tests
  536  * (but improves user and sys times oddly enough), and saves approximately
  537  * 5% in power consumption on an idle machine (tests w/2xCPU 1.1GHz P3).
  538  *
  539  * XXX we need to have a cpu mask of idle cpus and generate an IPI or
  540  * otherwise generate some sort of interrupt to wake up cpus sitting in HLT.
  541  * Then we can have our cake and eat it too.
  542  *
  543  * XXX I'm turning it on for SMP as well by default for now.  It seems to
  544  * help lock contention somewhat, and this is critical for HTT. -Peter
  545  */
  546 static int      cpu_idle_hlt = 1;
  547 TUNABLE_INT("machdep.cpu_idle_hlt", &cpu_idle_hlt);
  548 SYSCTL_INT(_machdep, OID_AUTO, cpu_idle_hlt, CTLFLAG_RW,
  549     &cpu_idle_hlt, 0, "Idle loop HLT enable");
  550 
  551 static void
  552 cpu_idle_default(void)
  553 {
  554         /*
  555          * we must absolutely guarentee that hlt is the
  556          * absolute next instruction after sti or we
  557          * introduce a timing window.
  558          */
  559         __asm __volatile("sti; hlt");
  560 }
  561 
  562 /*
  563  * Note that we have to be careful here to avoid a race between checking
  564  * sched_runnable() and actually halting.  If we don't do this, we may waste
  565  * the time between calling hlt and the next interrupt even though there
  566  * is a runnable process.
  567  */
  568 void
  569 cpu_idle(void)
  570 {
  571 
  572 #ifdef SMP
  573         if (mp_grab_cpu_hlt())
  574                 return;
  575 #endif
  576         if (cpu_idle_hlt) {
  577                 disable_intr();
  578                 if (sched_runnable())
  579                         enable_intr();
  580                 else
  581                         (*cpu_idle_hook)();
  582         }
  583 }
  584 
  585 /* Other subsystems (e.g., ACPI) can hook this later. */
  586 void (*cpu_idle_hook)(void) = cpu_idle_default;
  587 
  588 /*
  589  * Clear registers on exec
  590  */
  591 void
  592 exec_setregs(td, entry, stack, ps_strings)
  593         struct thread *td;
  594         u_long entry;
  595         u_long stack;
  596         u_long ps_strings;
  597 {
  598         struct trapframe *regs = td->td_frame;
  599         struct pcb *pcb = td->td_pcb;
  600         
  601         critical_enter();
  602         wrmsr(MSR_FSBASE, 0);
  603         wrmsr(MSR_KGSBASE, 0);  /* User value while we're in the kernel */
  604         pcb->pcb_fsbase = 0;
  605         pcb->pcb_gsbase = 0;
  606         critical_exit();
  607         pcb->pcb_flags &= ~(PCB_32BIT | PCB_GS32BIT);
  608         load_ds(_udatasel);
  609         load_es(_udatasel);
  610         load_fs(_udatasel);
  611         load_gs(_udatasel);
  612         pcb->pcb_ds = _udatasel;
  613         pcb->pcb_es = _udatasel;
  614         pcb->pcb_fs = _udatasel;
  615         pcb->pcb_gs = _udatasel;
  616 
  617         bzero((char *)regs, sizeof(struct trapframe));
  618         regs->tf_rip = entry;
  619         regs->tf_rsp = ((stack - 8) & ~0xFul) + 8;
  620         regs->tf_rdi = stack;           /* argv */
  621         regs->tf_rflags = PSL_USER | (regs->tf_rflags & PSL_T);
  622         regs->tf_ss = _udatasel;
  623         regs->tf_cs = _ucodesel;
  624 
  625         /*
  626          * Reset the hardware debug registers if they were in use.
  627          * They won't have any meaning for the newly exec'd process.
  628          */
  629         if (pcb->pcb_flags & PCB_DBREGS) {
  630                 pcb->pcb_dr0 = 0;
  631                 pcb->pcb_dr1 = 0;
  632                 pcb->pcb_dr2 = 0;
  633                 pcb->pcb_dr3 = 0;
  634                 pcb->pcb_dr6 = 0;
  635                 pcb->pcb_dr7 = 0;
  636                 if (pcb == PCPU_GET(curpcb)) {
  637                         /*
  638                          * Clear the debug registers on the running
  639                          * CPU, otherwise they will end up affecting
  640                          * the next process we switch to.
  641                          */
  642                         reset_dbregs();
  643                 }
  644                 pcb->pcb_flags &= ~PCB_DBREGS;
  645         }
  646 
  647         /*
  648          * Drop the FP state if we hold it, so that the process gets a
  649          * clean FP state if it uses the FPU again.
  650          */
  651         fpstate_drop(td);
  652 }
  653 
  654 void
  655 cpu_setregs(void)
  656 {
  657         register_t cr0;
  658 
  659         cr0 = rcr0();
  660         /*
  661          * CR0_MP, CR0_NE and CR0_TS are also set by npx_probe() for the
  662          * BSP.  See the comments there about why we set them.
  663          */
  664         cr0 |= CR0_MP | CR0_NE | CR0_TS | CR0_WP | CR0_AM;
  665         load_cr0(cr0);
  666 }
  667 
  668 /*
  669  * Initialize amd64 and configure to run kernel
  670  */
  671 
  672 /*
  673  * Initialize segments & interrupt table
  674  */
  675 
  676 struct user_segment_descriptor gdt[NGDT * MAXCPU];/* global descriptor tables */
  677 static struct gate_descriptor idt0[NIDT];
  678 struct gate_descriptor *idt = &idt0[0]; /* interrupt descriptor table */
  679 
  680 static char dblfault_stack[PAGE_SIZE] __aligned(16);
  681 
  682 struct amd64tss common_tss[MAXCPU];
  683 
  684 /* software prototypes -- in more palatable form */
  685 struct soft_segment_descriptor gdt_segs[] = {
  686 /* GNULL_SEL    0 Null Descriptor */
  687 {       0x0,                    /* segment base address  */
  688         0x0,                    /* length */
  689         0,                      /* segment type */
  690         0,                      /* segment descriptor priority level */
  691         0,                      /* segment descriptor present */
  692         0,                      /* long */
  693         0,                      /* default 32 vs 16 bit size */
  694         0                       /* limit granularity (byte/page units)*/ },
  695 /* GCODE_SEL    1 Code Descriptor for kernel */
  696 {       0x0,                    /* segment base address  */
  697         0xfffff,                /* length - all address space */
  698         SDT_MEMERA,             /* segment type */
  699         SEL_KPL,                /* segment descriptor priority level */
  700         1,                      /* segment descriptor present */
  701         1,                      /* long */
  702         0,                      /* default 32 vs 16 bit size */
  703         1                       /* limit granularity (byte/page units)*/ },
  704 /* GDATA_SEL    2 Data Descriptor for kernel */
  705 {       0x0,                    /* segment base address  */
  706         0xfffff,                /* length - all address space */
  707         SDT_MEMRWA,             /* segment type */
  708         SEL_KPL,                /* segment descriptor priority level */
  709         1,                      /* segment descriptor present */
  710         1,                      /* long */
  711         0,                      /* default 32 vs 16 bit size */
  712         1                       /* limit granularity (byte/page units)*/ },
  713 /* GUCODE32_SEL 3 32 bit Code Descriptor for user */
  714 {       0x0,                    /* segment base address  */
  715         0xfffff,                /* length - all address space */
  716         SDT_MEMERA,             /* segment type */
  717         SEL_UPL,                /* segment descriptor priority level */
  718         1,                      /* segment descriptor present */
  719         0,                      /* long */
  720         1,                      /* default 32 vs 16 bit size */
  721         1                       /* limit granularity (byte/page units)*/ },
  722 /* GUDATA_SEL   4 32/64 bit Data Descriptor for user */
  723 {       0x0,                    /* segment base address  */
  724         0xfffff,                /* length - all address space */
  725         SDT_MEMRWA,             /* segment type */
  726         SEL_UPL,                /* segment descriptor priority level */
  727         1,                      /* segment descriptor present */
  728         0,                      /* long */
  729         1,                      /* default 32 vs 16 bit size */
  730         1                       /* limit granularity (byte/page units)*/ },
  731 /* GUCODE_SEL   5 64 bit Code Descriptor for user */
  732 {       0x0,                    /* segment base address  */
  733         0xfffff,                /* length - all address space */
  734         SDT_MEMERA,             /* segment type */
  735         SEL_UPL,                /* segment descriptor priority level */
  736         1,                      /* segment descriptor present */
  737         1,                      /* long */
  738         0,                      /* default 32 vs 16 bit size */
  739         1                       /* limit granularity (byte/page units)*/ },
  740 /* GPROC0_SEL   6 Proc 0 Tss Descriptor */
  741 {
  742         0x0,                    /* segment base address */
  743         sizeof(struct amd64tss)-1,/* length */
  744         SDT_SYSTSS,             /* segment type */
  745         SEL_KPL,                /* segment descriptor priority level */
  746         1,                      /* segment descriptor present */
  747         0,                      /* long */
  748         0,                      /* unused - default 32 vs 16 bit size */
  749         0                       /* limit granularity (byte/page units)*/ },
  750 /* Actually, the TSS is a system descriptor which is double size */
  751 {       0x0,                    /* segment base address  */
  752         0x0,                    /* length */
  753         0,                      /* segment type */
  754         0,                      /* segment descriptor priority level */
  755         0,                      /* segment descriptor present */
  756         0,                      /* long */
  757         0,                      /* default 32 vs 16 bit size */
  758         0                       /* limit granularity (byte/page units)*/ },
  759 /* GUGS32_SEL   8 32 bit GS Descriptor for user */
  760 {       0x0,                    /* segment base address  */
  761         0xfffff,                /* length - all address space */
  762         SDT_MEMRWA,             /* segment type */
  763         SEL_UPL,                /* segment descriptor priority level */
  764         1,                      /* segment descriptor present */
  765         0,                      /* long */
  766         1,                      /* default 32 vs 16 bit size */
  767         1                       /* limit granularity (byte/page units)*/ },
  768 };
  769 
  770 void
  771 setidt(idx, func, typ, dpl, ist)
  772         int idx;
  773         inthand_t *func;
  774         int typ;
  775         int dpl;
  776         int ist;
  777 {
  778         struct gate_descriptor *ip;
  779 
  780         ip = idt + idx;
  781         ip->gd_looffset = (uintptr_t)func;
  782         ip->gd_selector = GSEL(GCODE_SEL, SEL_KPL);
  783         ip->gd_ist = ist;
  784         ip->gd_xx = 0;
  785         ip->gd_type = typ;
  786         ip->gd_dpl = dpl;
  787         ip->gd_p = 1;
  788         ip->gd_hioffset = ((uintptr_t)func)>>16 ;
  789 }
  790 
  791 extern inthand_t
  792         IDTVEC(div), IDTVEC(dbg), IDTVEC(nmi), IDTVEC(bpt), IDTVEC(ofl),
  793         IDTVEC(bnd), IDTVEC(ill), IDTVEC(dna), IDTVEC(fpusegm),
  794         IDTVEC(tss), IDTVEC(missing), IDTVEC(stk), IDTVEC(prot),
  795         IDTVEC(page), IDTVEC(mchk), IDTVEC(rsvd), IDTVEC(fpu), IDTVEC(align),
  796         IDTVEC(xmm), IDTVEC(dblfault),
  797         IDTVEC(fast_syscall), IDTVEC(fast_syscall32);
  798 
  799 void
  800 sdtossd(sd, ssd)
  801         struct user_segment_descriptor *sd;
  802         struct soft_segment_descriptor *ssd;
  803 {
  804 
  805         ssd->ssd_base  = (sd->sd_hibase << 24) | sd->sd_lobase;
  806         ssd->ssd_limit = (sd->sd_hilimit << 16) | sd->sd_lolimit;
  807         ssd->ssd_type  = sd->sd_type;
  808         ssd->ssd_dpl   = sd->sd_dpl;
  809         ssd->ssd_p     = sd->sd_p;
  810         ssd->ssd_long  = sd->sd_long;
  811         ssd->ssd_def32 = sd->sd_def32;
  812         ssd->ssd_gran  = sd->sd_gran;
  813 }
  814 
  815 void
  816 ssdtosd(ssd, sd)
  817         struct soft_segment_descriptor *ssd;
  818         struct user_segment_descriptor *sd;
  819 {
  820 
  821         sd->sd_lobase = (ssd->ssd_base) & 0xffffff;
  822         sd->sd_hibase = (ssd->ssd_base >> 24) & 0xff;
  823         sd->sd_lolimit = (ssd->ssd_limit) & 0xffff;
  824         sd->sd_hilimit = (ssd->ssd_limit >> 16) & 0xf;
  825         sd->sd_type  = ssd->ssd_type;
  826         sd->sd_dpl   = ssd->ssd_dpl;
  827         sd->sd_p     = ssd->ssd_p;
  828         sd->sd_long  = ssd->ssd_long;
  829         sd->sd_def32 = ssd->ssd_def32;
  830         sd->sd_gran  = ssd->ssd_gran;
  831 }
  832 
  833 void
  834 ssdtosyssd(ssd, sd)
  835         struct soft_segment_descriptor *ssd;
  836         struct system_segment_descriptor *sd;
  837 {
  838 
  839         sd->sd_lobase = (ssd->ssd_base) & 0xffffff;
  840         sd->sd_hibase = (ssd->ssd_base >> 24) & 0xfffffffffful;
  841         sd->sd_lolimit = (ssd->ssd_limit) & 0xffff;
  842         sd->sd_hilimit = (ssd->ssd_limit >> 16) & 0xf;
  843         sd->sd_type  = ssd->ssd_type;
  844         sd->sd_dpl   = ssd->ssd_dpl;
  845         sd->sd_p     = ssd->ssd_p;
  846         sd->sd_gran  = ssd->ssd_gran;
  847 }
  848 
  849 #if !defined(DEV_ATPIC) && defined(DEV_ISA)
  850 #include <isa/isavar.h>
  851 u_int
  852 isa_irq_pending(void)
  853 {
  854 
  855         return (0);
  856 }
  857 #endif
  858 
  859 u_int basemem;
  860 
  861 /*
  862  * Populate the (physmap) array with base/bound pairs describing the
  863  * available physical memory in the system, then test this memory and
  864  * build the phys_avail array describing the actually-available memory.
  865  *
  866  * If we cannot accurately determine the physical memory map, then use
  867  * value from the 0xE801 call, and failing that, the RTC.
  868  *
  869  * Total memory size may be set by the kernel environment variable
  870  * hw.physmem or the compile-time define MAXMEM.
  871  *
  872  * XXX first should be vm_paddr_t.
  873  */
  874 static void
  875 getmemsize(caddr_t kmdp, u_int64_t first)
  876 {
  877         int i, off, physmap_idx, pa_indx, da_indx;
  878         vm_paddr_t pa, physmap[PHYSMAP_SIZE];
  879         u_long physmem_tunable;
  880         pt_entry_t *pte;
  881         struct bios_smap *smapbase, *smap, *smapend;
  882         u_int32_t smapsize;
  883         quad_t dcons_addr, dcons_size;
  884 
  885         bzero(physmap, sizeof(physmap));
  886         basemem = 0;
  887         physmap_idx = 0;
  888 
  889         /*
  890          * get memory map from INT 15:E820, kindly supplied by the loader.
  891          *
  892          * subr_module.c says:
  893          * "Consumer may safely assume that size value precedes data."
  894          * ie: an int32_t immediately precedes smap.
  895          */
  896         smapbase = (struct bios_smap *)preload_search_info(kmdp,
  897             MODINFO_METADATA | MODINFOMD_SMAP);
  898         if (smapbase == NULL)
  899                 panic("No BIOS smap info from loader!");
  900 
  901         smapsize = *((u_int32_t *)smapbase - 1);
  902         smapend = (struct bios_smap *)((uintptr_t)smapbase + smapsize);
  903 
  904         for (smap = smapbase; smap < smapend; smap++) {
  905                 if (boothowto & RB_VERBOSE)
  906                         printf("SMAP type=%02x base=%016lx len=%016lx\n",
  907                             smap->type, smap->base, smap->length);
  908 
  909                 if (smap->type != SMAP_TYPE_MEMORY)
  910                         continue;
  911 
  912                 if (smap->length == 0)
  913                         continue;
  914 
  915                 for (i = 0; i <= physmap_idx; i += 2) {
  916                         if (smap->base < physmap[i + 1]) {
  917                                 if (boothowto & RB_VERBOSE)
  918                                         printf(
  919         "Overlapping or non-monotonic memory region, ignoring second region\n");
  920                                 continue;
  921                         }
  922                 }
  923 
  924                 if (smap->base == physmap[physmap_idx + 1]) {
  925                         physmap[physmap_idx + 1] += smap->length;
  926                         continue;
  927                 }
  928 
  929                 physmap_idx += 2;
  930                 if (physmap_idx == PHYSMAP_SIZE) {
  931                         printf(
  932                 "Too many segments in the physical address map, giving up\n");
  933                         break;
  934                 }
  935                 physmap[physmap_idx] = smap->base;
  936                 physmap[physmap_idx + 1] = smap->base + smap->length;
  937         }
  938 
  939         /*
  940          * Find the 'base memory' segment for SMP
  941          */
  942         basemem = 0;
  943         for (i = 0; i <= physmap_idx; i += 2) {
  944                 if (physmap[i] == 0x00000000) {
  945                         basemem = physmap[i + 1] / 1024;
  946                         break;
  947                 }
  948         }
  949         if (basemem == 0)
  950                 panic("BIOS smap did not include a basemem segment!");
  951 
  952 #ifdef SMP
  953         /* make hole for AP bootstrap code */
  954         physmap[1] = mp_bootaddress(physmap[1] / 1024);
  955 #endif
  956 
  957         /*
  958          * Maxmem isn't the "maximum memory", it's one larger than the
  959          * highest page of the physical address space.  It should be
  960          * called something like "Maxphyspage".  We may adjust this
  961          * based on ``hw.physmem'' and the results of the memory test.
  962          */
  963         Maxmem = atop(physmap[physmap_idx + 1]);
  964 
  965 #ifdef MAXMEM
  966         Maxmem = MAXMEM / 4;
  967 #endif
  968 
  969         if (TUNABLE_ULONG_FETCH("hw.physmem", &physmem_tunable))
  970                 Maxmem = atop(physmem_tunable);
  971 
  972         /*
  973          * Don't allow MAXMEM or hw.physmem to extend the amount of memory
  974          * in the system.
  975          */
  976         if (Maxmem > atop(physmap[physmap_idx + 1]))
  977                 Maxmem = atop(physmap[physmap_idx + 1]);
  978 
  979         if (atop(physmap[physmap_idx + 1]) != Maxmem &&
  980             (boothowto & RB_VERBOSE))
  981                 printf("Physical memory use set to %ldK\n", Maxmem * 4);
  982 
  983         /* call pmap initialization to make new kernel address space */
  984         pmap_bootstrap(&first);
  985 
  986         /*
  987          * Size up each available chunk of physical memory.
  988          */
  989         physmap[0] = PAGE_SIZE;         /* mask off page 0 */
  990         pa_indx = 0;
  991         da_indx = 1;
  992         phys_avail[pa_indx++] = physmap[0];
  993         phys_avail[pa_indx] = physmap[0];
  994         dump_avail[da_indx] = physmap[0];
  995         pte = CMAP1;
  996 
  997         /*
  998          * Get dcons buffer address
  999          */
 1000         if (getenv_quad("dcons.addr", &dcons_addr) == 0 ||
 1001             getenv_quad("dcons.size", &dcons_size) == 0)
 1002                 dcons_addr = 0;
 1003 
 1004         /*
 1005          * physmap is in bytes, so when converting to page boundaries,
 1006          * round up the start address and round down the end address.
 1007          */
 1008         for (i = 0; i <= physmap_idx; i += 2) {
 1009                 vm_paddr_t end;
 1010 
 1011                 end = ptoa((vm_paddr_t)Maxmem);
 1012                 if (physmap[i + 1] < end)
 1013                         end = trunc_page(physmap[i + 1]);
 1014                 for (pa = round_page(physmap[i]); pa < end; pa += PAGE_SIZE) {
 1015                         int tmp, page_bad, full;
 1016                         int *ptr = (int *)CADDR1;
 1017 
 1018                         full = FALSE;
 1019                         /*
 1020                          * block out kernel memory as not available.
 1021                          */
 1022                         if (pa >= 0x100000 && pa < first)
 1023                                 goto do_dump_avail;
 1024 
 1025                         /*
 1026                          * block out dcons buffer
 1027                          */
 1028                         if (dcons_addr > 0
 1029                             && pa >= trunc_page(dcons_addr)
 1030                             && pa < dcons_addr + dcons_size)
 1031                                 goto do_dump_avail;
 1032 
 1033                         page_bad = FALSE;
 1034 
 1035                         /*
 1036                          * map page into kernel: valid, read/write,non-cacheable
 1037                          */
 1038                         *pte = pa | PG_V | PG_RW | PG_N;
 1039                         invltlb();
 1040 
 1041                         tmp = *(int *)ptr;
 1042                         /*
 1043                          * Test for alternating 1's and 0's
 1044                          */
 1045                         *(volatile int *)ptr = 0xaaaaaaaa;
 1046                         if (*(volatile int *)ptr != 0xaaaaaaaa)
 1047                                 page_bad = TRUE;
 1048                         /*
 1049                          * Test for alternating 0's and 1's
 1050                          */
 1051                         *(volatile int *)ptr = 0x55555555;
 1052                         if (*(volatile int *)ptr != 0x55555555)
 1053                                 page_bad = TRUE;
 1054                         /*
 1055                          * Test for all 1's
 1056                          */
 1057                         *(volatile int *)ptr = 0xffffffff;
 1058                         if (*(volatile int *)ptr != 0xffffffff)
 1059                                 page_bad = TRUE;
 1060                         /*
 1061                          * Test for all 0's
 1062                          */
 1063                         *(volatile int *)ptr = 0x0;
 1064                         if (*(volatile int *)ptr != 0x0)
 1065                                 page_bad = TRUE;
 1066                         /*
 1067                          * Restore original value.
 1068                          */
 1069                         *(int *)ptr = tmp;
 1070 
 1071                         /*
 1072                          * Adjust array of valid/good pages.
 1073                          */
 1074                         if (page_bad == TRUE)
 1075                                 continue;
 1076                         /*
 1077                          * If this good page is a continuation of the
 1078                          * previous set of good pages, then just increase
 1079                          * the end pointer. Otherwise start a new chunk.
 1080                          * Note that "end" points one higher than end,
 1081                          * making the range >= start and < end.
 1082                          * If we're also doing a speculative memory
 1083                          * test and we at or past the end, bump up Maxmem
 1084                          * so that we keep going. The first bad page
 1085                          * will terminate the loop.
 1086                          */
 1087                         if (phys_avail[pa_indx] == pa) {
 1088                                 phys_avail[pa_indx] += PAGE_SIZE;
 1089                         } else {
 1090                                 pa_indx++;
 1091                                 if (pa_indx == PHYS_AVAIL_ARRAY_END) {
 1092                                         printf(
 1093                 "Too many holes in the physical address space, giving up\n");
 1094                                         pa_indx--;
 1095                                         full = TRUE;
 1096                                         goto do_dump_avail;
 1097                                 }
 1098                                 phys_avail[pa_indx++] = pa;     /* start */
 1099                                 phys_avail[pa_indx] = pa + PAGE_SIZE; /* end */
 1100                         }
 1101                         physmem++;
 1102 do_dump_avail:
 1103                         if (dump_avail[da_indx] == pa) {
 1104                                 dump_avail[da_indx] += PAGE_SIZE;
 1105                         } else {
 1106                                 da_indx++;
 1107                                 if (da_indx == DUMP_AVAIL_ARRAY_END) {
 1108                                         da_indx--;
 1109                                         goto do_next;
 1110                                 }
 1111                                 dump_avail[da_indx++] = pa; /* start */
 1112                                 dump_avail[da_indx] = pa + PAGE_SIZE; /* end */
 1113                         }
 1114 do_next:
 1115                         if (full)
 1116                                 break;
 1117                 }
 1118         }
 1119         *pte = 0;
 1120         invltlb();
 1121 
 1122         /*
 1123          * XXX
 1124          * The last chunk must contain at least one page plus the message
 1125          * buffer to avoid complicating other code (message buffer address
 1126          * calculation, etc.).
 1127          */
 1128         while (phys_avail[pa_indx - 1] + PAGE_SIZE +
 1129             round_page(MSGBUF_SIZE) >= phys_avail[pa_indx]) {
 1130                 physmem -= atop(phys_avail[pa_indx] - phys_avail[pa_indx - 1]);
 1131                 phys_avail[pa_indx--] = 0;
 1132                 phys_avail[pa_indx--] = 0;
 1133         }
 1134 
 1135         Maxmem = atop(phys_avail[pa_indx]);
 1136 
 1137         /* Trim off space for the message buffer. */
 1138         phys_avail[pa_indx] -= round_page(MSGBUF_SIZE);
 1139 
 1140         /* Map the message buffer. */
 1141         for (off = 0; off < round_page(MSGBUF_SIZE); off += PAGE_SIZE)
 1142                 pmap_kenter((vm_offset_t)msgbufp + off, phys_avail[pa_indx] +
 1143                     off);
 1144 }
 1145 
 1146 u_int64_t
 1147 hammer_time(u_int64_t modulep, u_int64_t physfree)
 1148 {
 1149         caddr_t kmdp;
 1150         int gsel_tss, x;
 1151         struct pcpu *pc;
 1152         u_int64_t msr;
 1153         char *env;
 1154 
 1155         thread0.td_kstack = physfree + KERNBASE;
 1156         bzero((void *)thread0.td_kstack, KSTACK_PAGES * PAGE_SIZE);
 1157         physfree += KSTACK_PAGES * PAGE_SIZE;
 1158         thread0.td_pcb = (struct pcb *)
 1159            (thread0.td_kstack + KSTACK_PAGES * PAGE_SIZE) - 1;
 1160 
 1161         /*
 1162          * This may be done better later if it gets more high level
 1163          * components in it. If so just link td->td_proc here.
 1164          */
 1165         proc_linkup0(&proc0, &thread0);
 1166 
 1167         preload_metadata = (caddr_t)(uintptr_t)(modulep + KERNBASE);
 1168         preload_bootstrap_relocate(KERNBASE);
 1169         kmdp = preload_search_by_type("elf kernel");
 1170         if (kmdp == NULL)
 1171                 kmdp = preload_search_by_type("elf64 kernel");
 1172         boothowto = MD_FETCH(kmdp, MODINFOMD_HOWTO, int);
 1173         kern_envp = MD_FETCH(kmdp, MODINFOMD_ENVP, char *) + KERNBASE;
 1174 #ifdef DDB
 1175         ksym_start = MD_FETCH(kmdp, MODINFOMD_SSYM, uintptr_t);
 1176         ksym_end = MD_FETCH(kmdp, MODINFOMD_ESYM, uintptr_t);
 1177 #endif
 1178 
 1179         /* Init basic tunables, hz etc */
 1180         init_param1();
 1181 
 1182         /*
 1183          * make gdt memory segments
 1184          */
 1185         gdt_segs[GPROC0_SEL].ssd_base = (uintptr_t)&common_tss[0];
 1186 
 1187         for (x = 0; x < NGDT; x++) {
 1188                 if (x != GPROC0_SEL && x != (GPROC0_SEL + 1))
 1189                         ssdtosd(&gdt_segs[x], &gdt[x]);
 1190         }
 1191         ssdtosyssd(&gdt_segs[GPROC0_SEL],
 1192             (struct system_segment_descriptor *)&gdt[GPROC0_SEL]);
 1193 
 1194         r_gdt.rd_limit = NGDT * sizeof(gdt[0]) - 1;
 1195         r_gdt.rd_base =  (long) gdt;
 1196         lgdt(&r_gdt);
 1197         pc = &__pcpu[0];
 1198 
 1199         wrmsr(MSR_FSBASE, 0);           /* User value */
 1200         wrmsr(MSR_GSBASE, (u_int64_t)pc);
 1201         wrmsr(MSR_KGSBASE, 0);          /* User value while in the kernel */
 1202 
 1203         pcpu_init(pc, 0, sizeof(struct pcpu));
 1204         PCPU_SET(prvspace, pc);
 1205         PCPU_SET(curthread, &thread0);
 1206         PCPU_SET(curpcb, thread0.td_pcb);
 1207         PCPU_SET(tssp, &common_tss[0]);
 1208         PCPU_SET(gs32p, &gdt[GUGS32_SEL]);
 1209 
 1210         /*
 1211          * Initialize mutexes.
 1212          *
 1213          * icu_lock: in order to allow an interrupt to occur in a critical
 1214          *           section, to set pcpu->ipending (etc...) properly, we
 1215          *           must be able to get the icu lock, so it can't be
 1216          *           under witness.
 1217          */
 1218         mutex_init();
 1219         mtx_init(&icu_lock, "icu", NULL, MTX_SPIN | MTX_NOWITNESS);
 1220 
 1221         /* exceptions */
 1222         for (x = 0; x < NIDT; x++)
 1223                 setidt(x, &IDTVEC(rsvd), SDT_SYSIGT, SEL_KPL, 0);
 1224         setidt(IDT_DE, &IDTVEC(div),  SDT_SYSIGT, SEL_KPL, 0);
 1225         setidt(IDT_DB, &IDTVEC(dbg),  SDT_SYSIGT, SEL_KPL, 0);
 1226         setidt(IDT_NMI, &IDTVEC(nmi),  SDT_SYSIGT, SEL_KPL, 1);
 1227         setidt(IDT_BP, &IDTVEC(bpt),  SDT_SYSIGT, SEL_UPL, 0);
 1228         setidt(IDT_OF, &IDTVEC(ofl),  SDT_SYSIGT, SEL_KPL, 0);
 1229         setidt(IDT_BR, &IDTVEC(bnd),  SDT_SYSIGT, SEL_KPL, 0);
 1230         setidt(IDT_UD, &IDTVEC(ill),  SDT_SYSIGT, SEL_KPL, 0);
 1231         setidt(IDT_NM, &IDTVEC(dna),  SDT_SYSIGT, SEL_KPL, 0);
 1232         setidt(IDT_DF, &IDTVEC(dblfault), SDT_SYSIGT, SEL_KPL, 1);
 1233         setidt(IDT_FPUGP, &IDTVEC(fpusegm),  SDT_SYSIGT, SEL_KPL, 0);
 1234         setidt(IDT_TS, &IDTVEC(tss),  SDT_SYSIGT, SEL_KPL, 0);
 1235         setidt(IDT_NP, &IDTVEC(missing),  SDT_SYSIGT, SEL_KPL, 0);
 1236         setidt(IDT_SS, &IDTVEC(stk),  SDT_SYSIGT, SEL_KPL, 0);
 1237         setidt(IDT_GP, &IDTVEC(prot),  SDT_SYSIGT, SEL_KPL, 0);
 1238         setidt(IDT_PF, &IDTVEC(page),  SDT_SYSIGT, SEL_KPL, 0);
 1239         setidt(IDT_MF, &IDTVEC(fpu),  SDT_SYSIGT, SEL_KPL, 0);
 1240         setidt(IDT_AC, &IDTVEC(align), SDT_SYSIGT, SEL_KPL, 0);
 1241         setidt(IDT_MC, &IDTVEC(mchk),  SDT_SYSIGT, SEL_KPL, 0);
 1242         setidt(IDT_XF, &IDTVEC(xmm), SDT_SYSIGT, SEL_KPL, 0);
 1243 
 1244         r_idt.rd_limit = sizeof(idt0) - 1;
 1245         r_idt.rd_base = (long) idt;
 1246         lidt(&r_idt);
 1247 
 1248         /*
 1249          * Initialize the i8254 before the console so that console
 1250          * initialization can use DELAY().
 1251          */
 1252         i8254_init();
 1253 
 1254         /*
 1255          * Initialize the console before we print anything out.
 1256          */
 1257         cninit();
 1258 
 1259 #ifdef DEV_ISA
 1260 #ifdef DEV_ATPIC
 1261         elcr_probe();
 1262         atpic_startup();
 1263 #else
 1264         /* Reset and mask the atpics and leave them shut down. */
 1265         atpic_reset();
 1266 
 1267         /*
 1268          * Point the ICU spurious interrupt vectors at the APIC spurious
 1269          * interrupt handler.
 1270          */
 1271         setidt(IDT_IO_INTS + 7, IDTVEC(spuriousint), SDT_SYSIGT, SEL_KPL, 0);
 1272         setidt(IDT_IO_INTS + 15, IDTVEC(spuriousint), SDT_SYSIGT, SEL_KPL, 0);
 1273 #endif
 1274 #else
 1275 #error "have you forgotten the isa device?";
 1276 #endif
 1277 
 1278         kdb_init();
 1279 
 1280 #ifdef KDB
 1281         if (boothowto & RB_KDB)
 1282                 kdb_enter_why(KDB_WHY_BOOTFLAGS,
 1283                     "Boot flags requested debugger");
 1284 #endif
 1285 
 1286         identify_cpu();         /* Final stage of CPU initialization */
 1287         initializecpu();        /* Initialize CPU registers */
 1288 
 1289         /* make an initial tss so cpu can get interrupt stack on syscall! */
 1290         common_tss[0].tss_rsp0 = thread0.td_kstack + \
 1291             KSTACK_PAGES * PAGE_SIZE - sizeof(struct pcb);
 1292         /* Ensure the stack is aligned to 16 bytes */
 1293         common_tss[0].tss_rsp0 &= ~0xFul;
 1294         PCPU_SET(rsp0, common_tss[0].tss_rsp0);
 1295 
 1296         /* doublefault stack space, runs on ist1 */
 1297         common_tss[0].tss_ist1 = (long)&dblfault_stack[sizeof(dblfault_stack)];
 1298 
 1299         /* Set the IO permission bitmap (empty due to tss seg limit) */
 1300         common_tss[0].tss_iobase = sizeof(struct amd64tss);
 1301 
 1302         gsel_tss = GSEL(GPROC0_SEL, SEL_KPL);
 1303         ltr(gsel_tss);
 1304 
 1305         /* Set up the fast syscall stuff */
 1306         msr = rdmsr(MSR_EFER) | EFER_SCE;
 1307         wrmsr(MSR_EFER, msr);
 1308         wrmsr(MSR_LSTAR, (u_int64_t)IDTVEC(fast_syscall));
 1309         wrmsr(MSR_CSTAR, (u_int64_t)IDTVEC(fast_syscall32));
 1310         msr = ((u_int64_t)GSEL(GCODE_SEL, SEL_KPL) << 32) |
 1311               ((u_int64_t)GSEL(GUCODE32_SEL, SEL_UPL) << 48);
 1312         wrmsr(MSR_STAR, msr);
 1313         wrmsr(MSR_SF_MASK, PSL_NT|PSL_T|PSL_I|PSL_C|PSL_D);
 1314 
 1315         getmemsize(kmdp, physfree);
 1316         init_param2(physmem);
 1317 
 1318         /* now running on new page tables, configured,and u/iom is accessible */
 1319 
 1320         msgbufinit(msgbufp, MSGBUF_SIZE);
 1321         fpuinit();
 1322 
 1323         /* transfer to user mode */
 1324 
 1325         _ucodesel = GSEL(GUCODE_SEL, SEL_UPL);
 1326         _udatasel = GSEL(GUDATA_SEL, SEL_UPL);
 1327         _ucode32sel = GSEL(GUCODE32_SEL, SEL_UPL);
 1328 
 1329         /* setup proc 0's pcb */
 1330         thread0.td_pcb->pcb_flags = 0; /* XXXKSE */
 1331         thread0.td_pcb->pcb_cr3 = KPML4phys;
 1332         thread0.td_frame = &proc0_tf;
 1333 
 1334         env = getenv("kernelname");
 1335         if (env != NULL)
 1336                 strlcpy(kernelname, env, sizeof(kernelname));
 1337 
 1338         /* Location of kernel stack for locore */
 1339         return ((u_int64_t)thread0.td_pcb);
 1340 }
 1341 
 1342 void
 1343 cpu_pcpu_init(struct pcpu *pcpu, int cpuid, size_t size)
 1344 {
 1345 
 1346         pcpu->pc_acpi_id = 0xffffffff;
 1347 }
 1348 
 1349 void
 1350 spinlock_enter(void)
 1351 {
 1352         struct thread *td;
 1353 
 1354         td = curthread;
 1355         if (td->td_md.md_spinlock_count == 0)
 1356                 td->td_md.md_saved_flags = intr_disable();
 1357         td->td_md.md_spinlock_count++;
 1358         critical_enter();
 1359 }
 1360 
 1361 void
 1362 spinlock_exit(void)
 1363 {
 1364         struct thread *td;
 1365 
 1366         td = curthread;
 1367         critical_exit();
 1368         td->td_md.md_spinlock_count--;
 1369         if (td->td_md.md_spinlock_count == 0)
 1370                 intr_restore(td->td_md.md_saved_flags);
 1371 }
 1372 
 1373 /*
 1374  * Construct a PCB from a trapframe. This is called from kdb_trap() where
 1375  * we want to start a backtrace from the function that caused us to enter
 1376  * the debugger. We have the context in the trapframe, but base the trace
 1377  * on the PCB. The PCB doesn't have to be perfect, as long as it contains
 1378  * enough for a backtrace.
 1379  */
 1380 void
 1381 makectx(struct trapframe *tf, struct pcb *pcb)
 1382 {
 1383 
 1384         pcb->pcb_r12 = tf->tf_r12;
 1385         pcb->pcb_r13 = tf->tf_r13;
 1386         pcb->pcb_r14 = tf->tf_r14;
 1387         pcb->pcb_r15 = tf->tf_r15;
 1388         pcb->pcb_rbp = tf->tf_rbp;
 1389         pcb->pcb_rbx = tf->tf_rbx;
 1390         pcb->pcb_rip = tf->tf_rip;
 1391         pcb->pcb_rsp = (ISPL(tf->tf_cs)) ? tf->tf_rsp : (long)(tf + 1) - 8;
 1392 }
 1393 
 1394 int
 1395 ptrace_set_pc(struct thread *td, unsigned long addr)
 1396 {
 1397         td->td_frame->tf_rip = addr;
 1398         return (0);
 1399 }
 1400 
 1401 int
 1402 ptrace_single_step(struct thread *td)
 1403 {
 1404         td->td_frame->tf_rflags |= PSL_T;
 1405         return (0);
 1406 }
 1407 
 1408 int
 1409 ptrace_clear_single_step(struct thread *td)
 1410 {
 1411         td->td_frame->tf_rflags &= ~PSL_T;
 1412         return (0);
 1413 }
 1414 
 1415 int
 1416 fill_regs(struct thread *td, struct reg *regs)
 1417 {
 1418         struct trapframe *tp;
 1419 
 1420         tp = td->td_frame;
 1421         regs->r_r15 = tp->tf_r15;
 1422         regs->r_r14 = tp->tf_r14;
 1423         regs->r_r13 = tp->tf_r13;
 1424         regs->r_r12 = tp->tf_r12;
 1425         regs->r_r11 = tp->tf_r11;
 1426         regs->r_r10 = tp->tf_r10;
 1427         regs->r_r9  = tp->tf_r9;
 1428         regs->r_r8  = tp->tf_r8;
 1429         regs->r_rdi = tp->tf_rdi;
 1430         regs->r_rsi = tp->tf_rsi;
 1431         regs->r_rbp = tp->tf_rbp;
 1432         regs->r_rbx = tp->tf_rbx;
 1433         regs->r_rdx = tp->tf_rdx;
 1434         regs->r_rcx = tp->tf_rcx;
 1435         regs->r_rax = tp->tf_rax;
 1436         regs->r_rip = tp->tf_rip;
 1437         regs->r_cs = tp->tf_cs;
 1438         regs->r_rflags = tp->tf_rflags;
 1439         regs->r_rsp = tp->tf_rsp;
 1440         regs->r_ss = tp->tf_ss;
 1441         return (0);
 1442 }
 1443 
 1444 int
 1445 set_regs(struct thread *td, struct reg *regs)
 1446 {
 1447         struct trapframe *tp;
 1448         register_t rflags;
 1449 
 1450         tp = td->td_frame;
 1451         rflags = regs->r_rflags & 0xffffffff;
 1452         if (!EFL_SECURE(rflags, tp->tf_rflags) || !CS_SECURE(regs->r_cs))
 1453                 return (EINVAL);
 1454         tp->tf_r15 = regs->r_r15;
 1455         tp->tf_r14 = regs->r_r14;
 1456         tp->tf_r13 = regs->r_r13;
 1457         tp->tf_r12 = regs->r_r12;
 1458         tp->tf_r11 = regs->r_r11;
 1459         tp->tf_r10 = regs->r_r10;
 1460         tp->tf_r9  = regs->r_r9;
 1461         tp->tf_r8  = regs->r_r8;
 1462         tp->tf_rdi = regs->r_rdi;
 1463         tp->tf_rsi = regs->r_rsi;
 1464         tp->tf_rbp = regs->r_rbp;
 1465         tp->tf_rbx = regs->r_rbx;
 1466         tp->tf_rdx = regs->r_rdx;
 1467         tp->tf_rcx = regs->r_rcx;
 1468         tp->tf_rax = regs->r_rax;
 1469         tp->tf_rip = regs->r_rip;
 1470         tp->tf_cs = regs->r_cs;
 1471         tp->tf_rflags = rflags;
 1472         tp->tf_rsp = regs->r_rsp;
 1473         tp->tf_ss = regs->r_ss;
 1474         td->td_pcb->pcb_flags |= PCB_FULLCTX;
 1475         return (0);
 1476 }
 1477 
 1478 /* XXX check all this stuff! */
 1479 /* externalize from sv_xmm */
 1480 static void
 1481 fill_fpregs_xmm(struct savefpu *sv_xmm, struct fpreg *fpregs)
 1482 {
 1483         struct envxmm *penv_fpreg = (struct envxmm *)&fpregs->fpr_env;
 1484         struct envxmm *penv_xmm = &sv_xmm->sv_env;
 1485         int i;
 1486 
 1487         /* pcb -> fpregs */
 1488         bzero(fpregs, sizeof(*fpregs));
 1489 
 1490         /* FPU control/status */
 1491         penv_fpreg->en_cw = penv_xmm->en_cw;
 1492         penv_fpreg->en_sw = penv_xmm->en_sw;
 1493         penv_fpreg->en_tw = penv_xmm->en_tw;
 1494         penv_fpreg->en_opcode = penv_xmm->en_opcode;
 1495         penv_fpreg->en_rip = penv_xmm->en_rip;
 1496         penv_fpreg->en_rdp = penv_xmm->en_rdp;
 1497         penv_fpreg->en_mxcsr = penv_xmm->en_mxcsr;
 1498         penv_fpreg->en_mxcsr_mask = penv_xmm->en_mxcsr_mask;
 1499 
 1500         /* FPU registers */
 1501         for (i = 0; i < 8; ++i)
 1502                 bcopy(sv_xmm->sv_fp[i].fp_acc.fp_bytes, fpregs->fpr_acc[i], 10);
 1503 
 1504         /* SSE registers */
 1505         for (i = 0; i < 16; ++i)
 1506                 bcopy(sv_xmm->sv_xmm[i].xmm_bytes, fpregs->fpr_xacc[i], 16);
 1507 }
 1508 
 1509 /* internalize from fpregs into sv_xmm */
 1510 static void
 1511 set_fpregs_xmm(struct fpreg *fpregs, struct savefpu *sv_xmm)
 1512 {
 1513         struct envxmm *penv_xmm = &sv_xmm->sv_env;
 1514         struct envxmm *penv_fpreg = (struct envxmm *)&fpregs->fpr_env;
 1515         int i;
 1516 
 1517         /* fpregs -> pcb */
 1518         /* FPU control/status */
 1519         penv_xmm->en_cw = penv_fpreg->en_cw;
 1520         penv_xmm->en_sw = penv_fpreg->en_sw;
 1521         penv_xmm->en_tw = penv_fpreg->en_tw;
 1522         penv_xmm->en_opcode = penv_fpreg->en_opcode;
 1523         penv_xmm->en_rip = penv_fpreg->en_rip;
 1524         penv_xmm->en_rdp = penv_fpreg->en_rdp;
 1525         penv_xmm->en_mxcsr = penv_fpreg->en_mxcsr;
 1526         penv_xmm->en_mxcsr_mask = penv_fpreg->en_mxcsr_mask & cpu_mxcsr_mask;
 1527 
 1528         /* FPU registers */
 1529         for (i = 0; i < 8; ++i)
 1530                 bcopy(fpregs->fpr_acc[i], sv_xmm->sv_fp[i].fp_acc.fp_bytes, 10);
 1531 
 1532         /* SSE registers */
 1533         for (i = 0; i < 16; ++i)
 1534                 bcopy(fpregs->fpr_xacc[i], sv_xmm->sv_xmm[i].xmm_bytes, 16);
 1535 }
 1536 
 1537 /* externalize from td->pcb */
 1538 int
 1539 fill_fpregs(struct thread *td, struct fpreg *fpregs)
 1540 {
 1541 
 1542         fill_fpregs_xmm(&td->td_pcb->pcb_save, fpregs);
 1543         return (0);
 1544 }
 1545 
 1546 /* internalize to td->pcb */
 1547 int
 1548 set_fpregs(struct thread *td, struct fpreg *fpregs)
 1549 {
 1550 
 1551         set_fpregs_xmm(fpregs, &td->td_pcb->pcb_save);
 1552         return (0);
 1553 }
 1554 
 1555 /*
 1556  * Get machine context.
 1557  */
 1558 int
 1559 get_mcontext(struct thread *td, mcontext_t *mcp, int flags)
 1560 {
 1561         struct trapframe *tp;
 1562 
 1563         tp = td->td_frame;
 1564         PROC_LOCK(curthread->td_proc);
 1565         mcp->mc_onstack = sigonstack(tp->tf_rsp);
 1566         PROC_UNLOCK(curthread->td_proc);
 1567         mcp->mc_r15 = tp->tf_r15;
 1568         mcp->mc_r14 = tp->tf_r14;
 1569         mcp->mc_r13 = tp->tf_r13;
 1570         mcp->mc_r12 = tp->tf_r12;
 1571         mcp->mc_r11 = tp->tf_r11;
 1572         mcp->mc_r10 = tp->tf_r10;
 1573         mcp->mc_r9  = tp->tf_r9;
 1574         mcp->mc_r8  = tp->tf_r8;
 1575         mcp->mc_rdi = tp->tf_rdi;
 1576         mcp->mc_rsi = tp->tf_rsi;
 1577         mcp->mc_rbp = tp->tf_rbp;
 1578         mcp->mc_rbx = tp->tf_rbx;
 1579         mcp->mc_rcx = tp->tf_rcx;
 1580         mcp->mc_rflags = tp->tf_rflags;
 1581         if (flags & GET_MC_CLEAR_RET) {
 1582                 mcp->mc_rax = 0;
 1583                 mcp->mc_rdx = 0;
 1584                 mcp->mc_rflags &= ~PSL_C;
 1585         } else {
 1586                 mcp->mc_rax = tp->tf_rax;
 1587                 mcp->mc_rdx = tp->tf_rdx;
 1588         }
 1589         mcp->mc_rip = tp->tf_rip;
 1590         mcp->mc_cs = tp->tf_cs;
 1591         mcp->mc_rsp = tp->tf_rsp;
 1592         mcp->mc_ss = tp->tf_ss;
 1593         mcp->mc_len = sizeof(*mcp);
 1594         get_fpcontext(td, mcp);
 1595         return (0);
 1596 }
 1597 
 1598 /*
 1599  * Set machine context.
 1600  *
 1601  * However, we don't set any but the user modifiable flags, and we won't
 1602  * touch the cs selector.
 1603  */
 1604 int
 1605 set_mcontext(struct thread *td, const mcontext_t *mcp)
 1606 {
 1607         struct trapframe *tp;
 1608         long rflags;
 1609         int ret;
 1610 
 1611         tp = td->td_frame;
 1612         if (mcp->mc_len != sizeof(*mcp))
 1613                 return (EINVAL);
 1614         rflags = (mcp->mc_rflags & PSL_USERCHANGE) |
 1615             (tp->tf_rflags & ~PSL_USERCHANGE);
 1616         ret = set_fpcontext(td, mcp);
 1617         if (ret != 0)
 1618                 return (ret);
 1619         tp->tf_r15 = mcp->mc_r15;
 1620         tp->tf_r14 = mcp->mc_r14;
 1621         tp->tf_r13 = mcp->mc_r13;
 1622         tp->tf_r12 = mcp->mc_r12;
 1623         tp->tf_r11 = mcp->mc_r11;
 1624         tp->tf_r10 = mcp->mc_r10;
 1625         tp->tf_r9  = mcp->mc_r9;
 1626         tp->tf_r8  = mcp->mc_r8;
 1627         tp->tf_rdi = mcp->mc_rdi;
 1628         tp->tf_rsi = mcp->mc_rsi;
 1629         tp->tf_rbp = mcp->mc_rbp;
 1630         tp->tf_rbx = mcp->mc_rbx;
 1631         tp->tf_rdx = mcp->mc_rdx;
 1632         tp->tf_rcx = mcp->mc_rcx;
 1633         tp->tf_rax = mcp->mc_rax;
 1634         tp->tf_rip = mcp->mc_rip;
 1635         tp->tf_rflags = rflags;
 1636         tp->tf_rsp = mcp->mc_rsp;
 1637         tp->tf_ss = mcp->mc_ss;
 1638         td->td_pcb->pcb_flags |= PCB_FULLCTX;
 1639         return (0);
 1640 }
 1641 
 1642 static void
 1643 get_fpcontext(struct thread *td, mcontext_t *mcp)
 1644 {
 1645 
 1646         mcp->mc_ownedfp = fpugetregs(td, (struct savefpu *)&mcp->mc_fpstate);
 1647         mcp->mc_fpformat = fpuformat();
 1648 }
 1649 
 1650 static int
 1651 set_fpcontext(struct thread *td, const mcontext_t *mcp)
 1652 {
 1653         struct savefpu *fpstate;
 1654 
 1655         if (mcp->mc_fpformat == _MC_FPFMT_NODEV)
 1656                 return (0);
 1657         else if (mcp->mc_fpformat != _MC_FPFMT_XMM)
 1658                 return (EINVAL);
 1659         else if (mcp->mc_ownedfp == _MC_FPOWNED_NONE)
 1660                 /* We don't care what state is left in the FPU or PCB. */
 1661                 fpstate_drop(td);
 1662         else if (mcp->mc_ownedfp == _MC_FPOWNED_FPU ||
 1663             mcp->mc_ownedfp == _MC_FPOWNED_PCB) {
 1664                 /*
 1665                  * XXX we violate the dubious requirement that fpusetregs()
 1666                  * be called with interrupts disabled.
 1667                  * XXX obsolete on trap-16 systems?
 1668                  */
 1669                 fpstate = (struct savefpu *)&mcp->mc_fpstate;
 1670                 fpstate->sv_env.en_mxcsr &= cpu_mxcsr_mask;
 1671                 fpusetregs(td, fpstate);
 1672         } else
 1673                 return (EINVAL);
 1674         return (0);
 1675 }
 1676 
 1677 void
 1678 fpstate_drop(struct thread *td)
 1679 {
 1680         register_t s;
 1681 
 1682         s = intr_disable();
 1683         if (PCPU_GET(fpcurthread) == td)
 1684                 fpudrop();
 1685         /*
 1686          * XXX force a full drop of the fpu.  The above only drops it if we
 1687          * owned it.
 1688          *
 1689          * XXX I don't much like fpugetregs()'s semantics of doing a full
 1690          * drop.  Dropping only to the pcb matches fnsave's behaviour.
 1691          * We only need to drop to !PCB_INITDONE in sendsig().  But
 1692          * sendsig() is the only caller of fpugetregs()... perhaps we just
 1693          * have too many layers.
 1694          */
 1695         curthread->td_pcb->pcb_flags &= ~PCB_FPUINITDONE;
 1696         intr_restore(s);
 1697 }
 1698 
 1699 int
 1700 fill_dbregs(struct thread *td, struct dbreg *dbregs)
 1701 {
 1702         struct pcb *pcb;
 1703 
 1704         if (td == NULL) {
 1705                 dbregs->dr[0] = rdr0();
 1706                 dbregs->dr[1] = rdr1();
 1707                 dbregs->dr[2] = rdr2();
 1708                 dbregs->dr[3] = rdr3();
 1709                 dbregs->dr[6] = rdr6();
 1710                 dbregs->dr[7] = rdr7();
 1711         } else {
 1712                 pcb = td->td_pcb;
 1713                 dbregs->dr[0] = pcb->pcb_dr0;
 1714                 dbregs->dr[1] = pcb->pcb_dr1;
 1715                 dbregs->dr[2] = pcb->pcb_dr2;
 1716                 dbregs->dr[3] = pcb->pcb_dr3;
 1717                 dbregs->dr[6] = pcb->pcb_dr6;
 1718                 dbregs->dr[7] = pcb->pcb_dr7;
 1719         }
 1720         dbregs->dr[4] = 0;
 1721         dbregs->dr[5] = 0;
 1722         dbregs->dr[8] = 0;
 1723         dbregs->dr[9] = 0;
 1724         dbregs->dr[10] = 0;
 1725         dbregs->dr[11] = 0;
 1726         dbregs->dr[12] = 0;
 1727         dbregs->dr[13] = 0;
 1728         dbregs->dr[14] = 0;
 1729         dbregs->dr[15] = 0;
 1730         return (0);
 1731 }
 1732 
 1733 int
 1734 set_dbregs(struct thread *td, struct dbreg *dbregs)
 1735 {
 1736         struct pcb *pcb;
 1737         int i;
 1738 
 1739         if (td == NULL) {
 1740                 load_dr0(dbregs->dr[0]);
 1741                 load_dr1(dbregs->dr[1]);
 1742                 load_dr2(dbregs->dr[2]);
 1743                 load_dr3(dbregs->dr[3]);
 1744                 load_dr6(dbregs->dr[6]);
 1745                 load_dr7(dbregs->dr[7]);
 1746         } else {
 1747                 /*
 1748                  * Don't let an illegal value for dr7 get set.  Specifically,
 1749                  * check for undefined settings.  Setting these bit patterns
 1750                  * result in undefined behaviour and can lead to an unexpected
 1751                  * TRCTRAP or a general protection fault right here.
 1752                  * Upper bits of dr6 and dr7 must not be set
 1753                  */
 1754                 for (i = 0; i < 4; i++) {
 1755                         if (DBREG_DR7_ACCESS(dbregs->dr[7], i) == 0x02)
 1756                                 return (EINVAL);
 1757                         if (td->td_frame->tf_cs == _ucode32sel &&
 1758                             DBREG_DR7_LEN(dbregs->dr[7], i) == DBREG_DR7_LEN_8)
 1759                                 return (EINVAL);
 1760                 }
 1761                 if ((dbregs->dr[6] & 0xffffffff00000000ul) != 0 ||
 1762                     (dbregs->dr[7] & 0xffffffff00000000ul) != 0)
 1763                         return (EINVAL);
 1764 
 1765                 pcb = td->td_pcb;
 1766 
 1767                 /*
 1768                  * Don't let a process set a breakpoint that is not within the
 1769                  * process's address space.  If a process could do this, it
 1770                  * could halt the system by setting a breakpoint in the kernel
 1771                  * (if ddb was enabled).  Thus, we need to check to make sure
 1772                  * that no breakpoints are being enabled for addresses outside
 1773                  * process's address space.
 1774                  *
 1775                  * XXX - what about when the watched area of the user's
 1776                  * address space is written into from within the kernel
 1777                  * ... wouldn't that still cause a breakpoint to be generated
 1778                  * from within kernel mode?
 1779                  */
 1780 
 1781                 if (DBREG_DR7_ENABLED(dbregs->dr[7], 0)) {
 1782                         /* dr0 is enabled */
 1783                         if (dbregs->dr[0] >= VM_MAXUSER_ADDRESS)
 1784                                 return (EINVAL);
 1785                 }
 1786                 if (DBREG_DR7_ENABLED(dbregs->dr[7], 1)) {
 1787                         /* dr1 is enabled */
 1788                         if (dbregs->dr[1] >= VM_MAXUSER_ADDRESS)
 1789                                 return (EINVAL);
 1790                 }
 1791                 if (DBREG_DR7_ENABLED(dbregs->dr[7], 2)) {
 1792                         /* dr2 is enabled */
 1793                         if (dbregs->dr[2] >= VM_MAXUSER_ADDRESS)
 1794                                 return (EINVAL);
 1795                 }
 1796                 if (DBREG_DR7_ENABLED(dbregs->dr[7], 3)) {
 1797                         /* dr3 is enabled */
 1798                         if (dbregs->dr[3] >= VM_MAXUSER_ADDRESS)
 1799                                 return (EINVAL);
 1800                 }
 1801 
 1802                 pcb->pcb_dr0 = dbregs->dr[0];
 1803                 pcb->pcb_dr1 = dbregs->dr[1];
 1804                 pcb->pcb_dr2 = dbregs->dr[2];
 1805                 pcb->pcb_dr3 = dbregs->dr[3];
 1806                 pcb->pcb_dr6 = dbregs->dr[6];
 1807                 pcb->pcb_dr7 = dbregs->dr[7];
 1808 
 1809                 pcb->pcb_flags |= PCB_DBREGS;
 1810         }
 1811 
 1812         return (0);
 1813 }
 1814 
 1815 void
 1816 reset_dbregs(void)
 1817 {
 1818 
 1819         load_dr7(0);    /* Turn off the control bits first */
 1820         load_dr0(0);
 1821         load_dr1(0);
 1822         load_dr2(0);
 1823         load_dr3(0);
 1824         load_dr6(0);
 1825 }
 1826 
 1827 /*
 1828  * Return > 0 if a hardware breakpoint has been hit, and the
 1829  * breakpoint was in user space.  Return 0, otherwise.
 1830  */
 1831 int
 1832 user_dbreg_trap(void)
 1833 {
 1834         u_int64_t dr7, dr6; /* debug registers dr6 and dr7 */
 1835         u_int64_t bp;       /* breakpoint bits extracted from dr6 */
 1836         int nbp;            /* number of breakpoints that triggered */
 1837         caddr_t addr[4];    /* breakpoint addresses */
 1838         int i;
 1839         
 1840         dr7 = rdr7();
 1841         if ((dr7 & 0x000000ff) == 0) {
 1842                 /*
 1843                  * all GE and LE bits in the dr7 register are zero,
 1844                  * thus the trap couldn't have been caused by the
 1845                  * hardware debug registers
 1846                  */
 1847                 return 0;
 1848         }
 1849 
 1850         nbp = 0;
 1851         dr6 = rdr6();
 1852         bp = dr6 & 0x0000000f;
 1853 
 1854         if (!bp) {
 1855                 /*
 1856                  * None of the breakpoint bits are set meaning this
 1857                  * trap was not caused by any of the debug registers
 1858                  */
 1859                 return 0;
 1860         }
 1861 
 1862         /*
 1863          * at least one of the breakpoints were hit, check to see
 1864          * which ones and if any of them are user space addresses
 1865          */
 1866 
 1867         if (bp & 0x01) {
 1868                 addr[nbp++] = (caddr_t)rdr0();
 1869         }
 1870         if (bp & 0x02) {
 1871                 addr[nbp++] = (caddr_t)rdr1();
 1872         }
 1873         if (bp & 0x04) {
 1874                 addr[nbp++] = (caddr_t)rdr2();
 1875         }
 1876         if (bp & 0x08) {
 1877                 addr[nbp++] = (caddr_t)rdr3();
 1878         }
 1879 
 1880         for (i = 0; i < nbp; i++) {
 1881                 if (addr[i] < (caddr_t)VM_MAXUSER_ADDRESS) {
 1882                         /*
 1883                          * addr[i] is in user space
 1884                          */
 1885                         return nbp;
 1886                 }
 1887         }
 1888 
 1889         /*
 1890          * None of the breakpoints are in user space.
 1891          */
 1892         return 0;
 1893 }
 1894 
 1895 #ifdef KDB
 1896 
 1897 /*
 1898  * Provide inb() and outb() as functions.  They are normally only
 1899  * available as macros calling inlined functions, thus cannot be
 1900  * called from the debugger.
 1901  *
 1902  * The actual code is stolen from <machine/cpufunc.h>, and de-inlined.
 1903  */
 1904 
 1905 #undef inb
 1906 #undef outb
 1907 
 1908 /* silence compiler warnings */
 1909 u_char inb(u_int);
 1910 void outb(u_int, u_char);
 1911 
 1912 u_char
 1913 inb(u_int port)
 1914 {
 1915         u_char  data;
 1916         /*
 1917          * We use %%dx and not %1 here because i/o is done at %dx and not at
 1918          * %edx, while gcc generates inferior code (movw instead of movl)
 1919          * if we tell it to load (u_short) port.
 1920          */
 1921         __asm __volatile("inb %%dx,%0" : "=a" (data) : "d" (port));
 1922         return (data);
 1923 }
 1924 
 1925 void
 1926 outb(u_int port, u_char data)
 1927 {
 1928         u_char  al;
 1929         /*
 1930          * Use an unnecessary assignment to help gcc's register allocator.
 1931          * This make a large difference for gcc-1.40 and a tiny difference
 1932          * for gcc-2.6.0.  For gcc-1.40, al had to be ``asm("ax")'' for
 1933          * best results.  gcc-2.6.0 can't handle this.
 1934          */
 1935         al = data;
 1936         __asm __volatile("outb %0,%%dx" : : "a" (al), "d" (port));
 1937 }
 1938 
 1939 #endif /* KDB */

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