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


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

FreeBSD/Linux Kernel Cross Reference
sys/i386/i386/vm_machdep.c

Version: -  FREEBSD  -  FREEBSD-12-STABLE  -  FREEBSD-12-0  -  FREEBSD-11-STABLE  -  FREEBSD-11-2  -  FREEBSD-11-1  -  FREEBSD-11-0  -  FREEBSD-10-STABLE  -  FREEBSD-10-4  -  FREEBSD-10-3  -  FREEBSD-10-2  -  FREEBSD-10-1  -  FREEBSD-10-0  -  FREEBSD-9-STABLE  -  FREEBSD-9-3  -  FREEBSD-9-2  -  FREEBSD-9-1  -  FREEBSD-9-0  -  FREEBSD-8-STABLE  -  FREEBSD-8-4  -  FREEBSD-8-3  -  FREEBSD-8-2  -  FREEBSD-8-1  -  FREEBSD-8-0  -  FREEBSD-7-STABLE  -  FREEBSD-7-4  -  FREEBSD-7-3  -  FREEBSD-7-2  -  FREEBSD-7-1  -  FREEBSD-7-0  -  FREEBSD-6-STABLE  -  FREEBSD-6-4  -  FREEBSD-6-3  -  FREEBSD-6-2  -  FREEBSD-6-1  -  FREEBSD-6-0  -  FREEBSD-5-STABLE  -  FREEBSD-5-5  -  FREEBSD-5-4  -  FREEBSD-5-3  -  FREEBSD-5-2  -  FREEBSD-5-1  -  FREEBSD-5-0  -  FREEBSD-4-STABLE  -  FREEBSD-3-STABLE  -  FREEBSD22  -  linux-2.6  -  linux-2.4.22  -  MK83  -  MK84  -  PLAN9  -  DFBSD  -  NETBSD  -  NETBSD5  -  NETBSD4  -  NETBSD3  -  NETBSD20  -  OPENBSD  -  xnu-517  -  xnu-792  -  xnu-792.6.70  -  xnu-1228  -  xnu-1456.1.26  -  xnu-1699.24.8  -  xnu-2050.18.24  -  OPENSOLARIS  -  minix-3-1-1 
SearchContext: -  none  -  3  -  10 

    1 /*-
    2  * Copyright (c) 1982, 1986 The Regents of the University of California.
    3  * Copyright (c) 1989, 1990 William Jolitz
    4  * Copyright (c) 1994 John Dyson
    5  * All rights reserved.
    6  *
    7  * This code is derived from software contributed to Berkeley by
    8  * the Systems Programming Group of the University of Utah Computer
    9  * Science Department, and William Jolitz.
   10  *
   11  * Redistribution and use in source and binary forms, with or without
   12  * modification, are permitted provided that the following conditions
   13  * are met:
   14  * 1. Redistributions of source code must retain the above copyright
   15  *    notice, this list of conditions and the following disclaimer.
   16  * 2. Redistributions in binary form must reproduce the above copyright
   17  *    notice, this list of conditions and the following disclaimer in the
   18  *    documentation and/or other materials provided with the distribution.
   19  * 3. All advertising materials mentioning features or use of this software
   20  *    must display the following acknowledgement:
   21  *      This product includes software developed by the University of
   22  *      California, Berkeley and its contributors.
   23  * 4. Neither the name of the University nor the names of its contributors
   24  *    may be used to endorse or promote products derived from this software
   25  *    without specific prior written permission.
   26  *
   27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   37  * SUCH DAMAGE.
   38  *
   39  *      from: @(#)vm_machdep.c  7.3 (Berkeley) 5/13/91
   40  *      Utah $Hdr: vm_machdep.c 1.16.1.1 89/06/23$
   41  */
   42 
   43 #include <sys/cdefs.h>
   44 __FBSDID("$FreeBSD: releng/6.2/sys/i386/i386/vm_machdep.c 161534 2006-08-22 16:52:42Z rink $");
   45 
   46 #include "opt_isa.h"
   47 #include "opt_npx.h"
   48 #include "opt_reset.h"
   49 #include "opt_cpu.h"
   50 #include "opt_xbox.h"
   51 
   52 #include <sys/param.h>
   53 #include <sys/systm.h>
   54 #include <sys/bio.h>
   55 #include <sys/buf.h>
   56 #include <sys/kse.h>
   57 #include <sys/kernel.h>
   58 #include <sys/ktr.h>
   59 #include <sys/lock.h>
   60 #include <sys/malloc.h>
   61 #include <sys/mbuf.h>
   62 #include <sys/mutex.h>
   63 #include <sys/pioctl.h>
   64 #include <sys/proc.h>
   65 #include <sys/sf_buf.h>
   66 #include <sys/smp.h>
   67 #include <sys/sched.h>
   68 #include <sys/sysctl.h>
   69 #include <sys/unistd.h>
   70 #include <sys/vnode.h>
   71 #include <sys/vmmeter.h>
   72 
   73 #include <machine/cpu.h>
   74 #include <machine/cputypes.h>
   75 #include <machine/md_var.h>
   76 #include <machine/pcb.h>
   77 #include <machine/pcb_ext.h>
   78 #include <machine/smp.h>
   79 #include <machine/vm86.h>
   80 
   81 #ifdef CPU_ELAN
   82 #include <machine/elan_mmcr.h>
   83 #endif
   84 
   85 #include <vm/vm.h>
   86 #include <vm/vm_extern.h>
   87 #include <vm/vm_kern.h>
   88 #include <vm/vm_page.h>
   89 #include <vm/vm_map.h>
   90 #include <vm/vm_param.h>
   91 
   92 #ifdef PC98
   93 #include <pc98/cbus/cbus.h>
   94 #else
   95 #include <i386/isa/isa.h>
   96 #endif
   97 
   98 #ifdef XBOX
   99 #include <machine/xbox.h>
  100 #endif
  101 
  102 #ifndef NSFBUFS
  103 #define NSFBUFS         (512 + maxusers * 16)
  104 #endif
  105 
  106 static void     cpu_reset_real(void);
  107 #ifdef SMP
  108 static void     cpu_reset_proxy(void);
  109 static u_int    cpu_reset_proxyid;
  110 static volatile u_int   cpu_reset_proxy_active;
  111 #endif
  112 static void     sf_buf_init(void *arg);
  113 SYSINIT(sock_sf, SI_SUB_MBUF, SI_ORDER_ANY, sf_buf_init, NULL)
  114 
  115 LIST_HEAD(sf_head, sf_buf);
  116 
  117 /*
  118  * A hash table of active sendfile(2) buffers
  119  */
  120 static struct sf_head *sf_buf_active;
  121 static u_long sf_buf_hashmask;
  122 
  123 #define SF_BUF_HASH(m)  (((m) - vm_page_array) & sf_buf_hashmask)
  124 
  125 static TAILQ_HEAD(, sf_buf) sf_buf_freelist;
  126 static u_int    sf_buf_alloc_want;
  127 
  128 /*
  129  * A lock used to synchronize access to the hash table and free list
  130  */
  131 static struct mtx sf_buf_lock;
  132 
  133 extern int      _ucodesel, _udatasel;
  134 
  135 /*
  136  * Finish a fork operation, with process p2 nearly set up.
  137  * Copy and update the pcb, set up the stack so that the child
  138  * ready to run and return to user mode.
  139  */
  140 void
  141 cpu_fork(td1, p2, td2, flags)
  142         register struct thread *td1;
  143         register struct proc *p2;
  144         struct thread *td2;
  145         int flags;
  146 {
  147         register struct proc *p1;
  148         struct pcb *pcb2;
  149         struct mdproc *mdp2;
  150 #ifdef DEV_NPX
  151         register_t savecrit;
  152 #endif
  153 
  154         p1 = td1->td_proc;
  155         if ((flags & RFPROC) == 0) {
  156                 if ((flags & RFMEM) == 0) {
  157                         /* unshare user LDT */
  158                         struct mdproc *mdp1 = &p1->p_md;
  159                         struct proc_ldt *pldt;
  160 
  161                         pldt = mdp1->md_ldt;
  162                         if (pldt && pldt->ldt_refcnt > 1) {
  163                                 pldt = user_ldt_alloc(mdp1, pldt->ldt_len);
  164                                 if (pldt == NULL)
  165                                         panic("could not copy LDT");
  166                                 mdp1->md_ldt = pldt;
  167                                 set_user_ldt(mdp1);
  168                                 user_ldt_free(td1);
  169                         }
  170                 }
  171                 return;
  172         }
  173 
  174         /* Ensure that p1's pcb is up to date. */
  175 #ifdef DEV_NPX
  176         if (td1 == curthread)
  177                 td1->td_pcb->pcb_gs = rgs();
  178         savecrit = intr_disable();
  179         if (PCPU_GET(fpcurthread) == td1)
  180                 npxsave(&td1->td_pcb->pcb_save);
  181         intr_restore(savecrit);
  182 #endif
  183 
  184         /* Point the pcb to the top of the stack */
  185         pcb2 = (struct pcb *)(td2->td_kstack +
  186             td2->td_kstack_pages * PAGE_SIZE) - 1;
  187         td2->td_pcb = pcb2;
  188 
  189         /* Copy p1's pcb */
  190         bcopy(td1->td_pcb, pcb2, sizeof(*pcb2));
  191 
  192         /* Point mdproc and then copy over td1's contents */
  193         mdp2 = &p2->p_md;
  194         bcopy(&p1->p_md, mdp2, sizeof(*mdp2));
  195 
  196         /*
  197          * Create a new fresh stack for the new process.
  198          * Copy the trap frame for the return to user mode as if from a
  199          * syscall.  This copies most of the user mode register values.
  200          * The -16 is so we can expand the trapframe if we go to vm86.
  201          */
  202         td2->td_frame = (struct trapframe *)((caddr_t)td2->td_pcb - 16) - 1;
  203         bcopy(td1->td_frame, td2->td_frame, sizeof(struct trapframe));
  204 
  205         td2->td_frame->tf_eax = 0;              /* Child returns zero */
  206         td2->td_frame->tf_eflags &= ~PSL_C;     /* success */
  207         td2->td_frame->tf_edx = 1;
  208 
  209         /*
  210          * If the parent process has the trap bit set (i.e. a debugger had
  211          * single stepped the process to the system call), we need to clear
  212          * the trap flag from the new frame unless the debugger had set PF_FORK
  213          * on the parent.  Otherwise, the child will receive a (likely
  214          * unexpected) SIGTRAP when it executes the first instruction after
  215          * returning  to userland.
  216          */
  217         if ((p1->p_pfsflags & PF_FORK) == 0)
  218                 td2->td_frame->tf_eflags &= ~PSL_T;
  219 
  220         /*
  221          * Set registers for trampoline to user mode.  Leave space for the
  222          * return address on stack.  These are the kernel mode register values.
  223          */
  224 #ifdef PAE
  225         pcb2->pcb_cr3 = vtophys(vmspace_pmap(p2->p_vmspace)->pm_pdpt);
  226 #else
  227         pcb2->pcb_cr3 = vtophys(vmspace_pmap(p2->p_vmspace)->pm_pdir);
  228 #endif
  229         pcb2->pcb_edi = 0;
  230         pcb2->pcb_esi = (int)fork_return;       /* fork_trampoline argument */
  231         pcb2->pcb_ebp = 0;
  232         pcb2->pcb_esp = (int)td2->td_frame - sizeof(void *);
  233         pcb2->pcb_ebx = (int)td2;               /* fork_trampoline argument */
  234         pcb2->pcb_eip = (int)fork_trampoline;
  235         pcb2->pcb_psl = PSL_KERNEL;             /* ints disabled */
  236         pcb2->pcb_gs = rgs();
  237         /*-
  238          * pcb2->pcb_dr*:       cloned above.
  239          * pcb2->pcb_savefpu:   cloned above.
  240          * pcb2->pcb_flags:     cloned above.
  241          * pcb2->pcb_onfault:   cloned above (always NULL here?).
  242          * pcb2->pcb_gs:        cloned above.
  243          * pcb2->pcb_ext:       cleared below.
  244          */
  245 
  246         /*
  247          * XXX don't copy the i/o pages.  this should probably be fixed.
  248          */
  249         pcb2->pcb_ext = 0;
  250 
  251         /* Copy the LDT, if necessary. */
  252         mtx_lock_spin(&sched_lock);
  253         if (mdp2->md_ldt != NULL) {
  254                 if (flags & RFMEM) {
  255                         mdp2->md_ldt->ldt_refcnt++;
  256                 } else {
  257                         mdp2->md_ldt = user_ldt_alloc(mdp2,
  258                             mdp2->md_ldt->ldt_len);
  259                         if (mdp2->md_ldt == NULL)
  260                                 panic("could not copy LDT");
  261                 }
  262         }
  263         mtx_unlock_spin(&sched_lock);
  264 
  265         /* Setup to release sched_lock in fork_exit(). */
  266         td2->td_md.md_spinlock_count = 1;
  267         td2->td_md.md_saved_flags = PSL_KERNEL | PSL_I;
  268 
  269         /*
  270          * Now, cpu_switch() can schedule the new process.
  271          * pcb_esp is loaded pointing to the cpu_switch() stack frame
  272          * containing the return address when exiting cpu_switch.
  273          * This will normally be to fork_trampoline(), which will have
  274          * %ebx loaded with the new proc's pointer.  fork_trampoline()
  275          * will set up a stack to call fork_return(p, frame); to complete
  276          * the return to user-mode.
  277          */
  278 }
  279 
  280 /*
  281  * Intercept the return address from a freshly forked process that has NOT
  282  * been scheduled yet.
  283  *
  284  * This is needed to make kernel threads stay in kernel mode.
  285  */
  286 void
  287 cpu_set_fork_handler(td, func, arg)
  288         struct thread *td;
  289         void (*func)(void *);
  290         void *arg;
  291 {
  292         /*
  293          * Note that the trap frame follows the args, so the function
  294          * is really called like this:  func(arg, frame);
  295          */
  296         td->td_pcb->pcb_esi = (int) func;       /* function */
  297         td->td_pcb->pcb_ebx = (int) arg;        /* first arg */
  298 }
  299 
  300 void
  301 cpu_exit(struct thread *td)
  302 {
  303 
  304         /*
  305          * If this process has a custom LDT, release it.  Reset pc->pcb_gs
  306          * and %gs before we free it in case they refer to an LDT entry.
  307          */
  308         if (td->td_proc->p_md.md_ldt) {
  309                 td->td_pcb->pcb_gs = _udatasel;
  310                 load_gs(_udatasel);
  311                 user_ldt_free(td);
  312         }
  313 }
  314 
  315 void
  316 cpu_thread_exit(struct thread *td)
  317 {
  318 
  319 #ifdef DEV_NPX
  320         if (td == PCPU_GET(fpcurthread))
  321                 npxdrop();
  322 #endif
  323 
  324         /* Disable any hardware breakpoints. */
  325         if (td->td_pcb->pcb_flags & PCB_DBREGS) {
  326                 reset_dbregs();
  327                 td->td_pcb->pcb_flags &= ~PCB_DBREGS;
  328         }
  329 }
  330 
  331 void
  332 cpu_thread_clean(struct thread *td)
  333 {
  334         struct pcb *pcb;
  335 
  336         pcb = td->td_pcb; 
  337         if (pcb->pcb_ext != NULL) {
  338                 /* XXXKSE  XXXSMP  not SMP SAFE.. what locks do we have? */
  339                 /* if (pcb->pcb_ext->ext_refcount-- == 1) ?? */
  340                 /*
  341                  * XXX do we need to move the TSS off the allocated pages
  342                  * before freeing them?  (not done here)
  343                  */
  344                 kmem_free(kernel_map, (vm_offset_t)pcb->pcb_ext,
  345                     ctob(IOPAGES + 1));
  346                 pcb->pcb_ext = NULL;
  347         }
  348 }
  349 
  350 void
  351 cpu_thread_swapin(struct thread *td)
  352 {
  353 }
  354 
  355 void
  356 cpu_thread_swapout(struct thread *td)
  357 {
  358 }
  359 
  360 void
  361 cpu_thread_setup(struct thread *td)
  362 {
  363 
  364         td->td_pcb = (struct pcb *)(td->td_kstack +
  365             td->td_kstack_pages * PAGE_SIZE) - 1;
  366         td->td_frame = (struct trapframe *)((caddr_t)td->td_pcb - 16) - 1;
  367         td->td_pcb->pcb_ext = NULL; 
  368 }
  369 
  370 /*
  371  * Initialize machine state (pcb and trap frame) for a new thread about to
  372  * upcall. Put enough state in the new thread's PCB to get it to go back 
  373  * userret(), where we can intercept it again to set the return (upcall)
  374  * Address and stack, along with those from upcals that are from other sources
  375  * such as those generated in thread_userret() itself.
  376  */
  377 void
  378 cpu_set_upcall(struct thread *td, struct thread *td0)
  379 {
  380         struct pcb *pcb2;
  381 
  382         /* Point the pcb to the top of the stack. */
  383         pcb2 = td->td_pcb;
  384 
  385         /*
  386          * Copy the upcall pcb.  This loads kernel regs.
  387          * Those not loaded individually below get their default
  388          * values here.
  389          *
  390          * XXXKSE It might be a good idea to simply skip this as
  391          * the values of the other registers may be unimportant.
  392          * This would remove any requirement for knowing the KSE
  393          * at this time (see the matching comment below for
  394          * more analysis) (need a good safe default).
  395          */
  396         bcopy(td0->td_pcb, pcb2, sizeof(*pcb2));
  397         pcb2->pcb_flags &= ~(PCB_NPXTRAP|PCB_NPXINITDONE);
  398 
  399         /*
  400          * Create a new fresh stack for the new thread.
  401          * The -16 is so we can expand the trapframe if we go to vm86.
  402          * Don't forget to set this stack value into whatever supplies
  403          * the address for the fault handlers.
  404          * The contexts are filled in at the time we actually DO the
  405          * upcall as only then do we know which KSE we got.
  406          */
  407         bcopy(td0->td_frame, td->td_frame, sizeof(struct trapframe));
  408 
  409         /*
  410          * Set registers for trampoline to user mode.  Leave space for the
  411          * return address on stack.  These are the kernel mode register values.
  412          */
  413 #ifdef PAE
  414         pcb2->pcb_cr3 = vtophys(vmspace_pmap(td->td_proc->p_vmspace)->pm_pdpt);
  415 #else
  416         pcb2->pcb_cr3 = vtophys(vmspace_pmap(td->td_proc->p_vmspace)->pm_pdir);
  417 #endif
  418         pcb2->pcb_edi = 0;
  419         pcb2->pcb_esi = (int)fork_return;                   /* trampoline arg */
  420         pcb2->pcb_ebp = 0;
  421         pcb2->pcb_esp = (int)td->td_frame - sizeof(void *); /* trampoline arg */
  422         pcb2->pcb_ebx = (int)td;                            /* trampoline arg */
  423         pcb2->pcb_eip = (int)fork_trampoline;
  424         pcb2->pcb_psl &= ~(PSL_I);      /* interrupts must be disabled */
  425         pcb2->pcb_gs = rgs();
  426         /*
  427          * If we didn't copy the pcb, we'd need to do the following registers:
  428          * pcb2->pcb_dr*:       cloned above.
  429          * pcb2->pcb_savefpu:   cloned above.
  430          * pcb2->pcb_flags:     cloned above.
  431          * pcb2->pcb_onfault:   cloned above (always NULL here?).
  432          * pcb2->pcb_gs:        cloned above.  XXXKSE ???
  433          * pcb2->pcb_ext:       cleared below.
  434          */
  435         pcb2->pcb_ext = NULL;
  436 
  437         /* Setup to release sched_lock in fork_exit(). */
  438         td->td_md.md_spinlock_count = 1;
  439         td->td_md.md_saved_flags = PSL_KERNEL | PSL_I;
  440 }
  441 
  442 /*
  443  * Set that machine state for performing an upcall that has to
  444  * be done in thread_userret() so that those upcalls generated
  445  * in thread_userret() itself can be done as well.
  446  */
  447 void
  448 cpu_set_upcall_kse(struct thread *td, void (*entry)(void *), void *arg,
  449         stack_t *stack)
  450 {
  451 
  452         /* 
  453          * Do any extra cleaning that needs to be done.
  454          * The thread may have optional components
  455          * that are not present in a fresh thread.
  456          * This may be a recycled thread so make it look
  457          * as though it's newly allocated.
  458          */
  459         cpu_thread_clean(td);
  460 
  461         /*
  462          * Set the trap frame to point at the beginning of the uts
  463          * function.
  464          */
  465         td->td_frame->tf_ebp = 0; 
  466         td->td_frame->tf_esp =
  467             (((int)stack->ss_sp + stack->ss_size - 4) & ~0x0f) - 4;
  468         td->td_frame->tf_eip = (int)entry;
  469 
  470         /*
  471          * Pass the address of the mailbox for this kse to the uts
  472          * function as a parameter on the stack.
  473          */
  474         suword((void *)(td->td_frame->tf_esp + sizeof(void *)),
  475             (int)arg);
  476 }
  477 
  478 int
  479 cpu_set_user_tls(struct thread *td, void *tls_base)
  480 {
  481         struct segment_descriptor sd;
  482         uint32_t base;
  483 
  484         /*
  485          * Construct a descriptor and store it in the pcb for
  486          * the next context switch.  Also store it in the gdt
  487          * so that the load of tf_fs into %fs will activate it
  488          * at return to userland.
  489          */
  490         base = (uint32_t)tls_base;
  491         sd.sd_lobase = base & 0xffffff;
  492         sd.sd_hibase = (base >> 24) & 0xff;
  493         sd.sd_lolimit = 0xffff; /* 4GB limit, wraps around */
  494         sd.sd_hilimit = 0xf;
  495         sd.sd_type  = SDT_MEMRWA;
  496         sd.sd_dpl   = SEL_UPL;
  497         sd.sd_p     = 1;
  498         sd.sd_xx    = 0;
  499         sd.sd_def32 = 1;
  500         sd.sd_gran  = 1;
  501         critical_enter();
  502         /* set %gs */
  503         td->td_pcb->pcb_gsd = sd;
  504         if (td == curthread) {
  505                 PCPU_GET(fsgs_gdt)[1] = sd;
  506                 load_gs(GSEL(GUGS_SEL, SEL_UPL));
  507         }
  508         critical_exit();
  509         return (0);
  510 }
  511 
  512 /*
  513  * Convert kernel VA to physical address
  514  */
  515 vm_paddr_t
  516 kvtop(void *addr)
  517 {
  518         vm_paddr_t pa;
  519 
  520         pa = pmap_kextract((vm_offset_t)addr);
  521         if (pa == 0)
  522                 panic("kvtop: zero page frame");
  523         return (pa);
  524 }
  525 
  526 #ifdef SMP
  527 static void
  528 cpu_reset_proxy()
  529 {
  530 
  531         cpu_reset_proxy_active = 1;
  532         while (cpu_reset_proxy_active == 1)
  533                 ;       /* Wait for other cpu to see that we've started */
  534         stop_cpus((1<<cpu_reset_proxyid));
  535         printf("cpu_reset_proxy: Stopped CPU %d\n", cpu_reset_proxyid);
  536         DELAY(1000000);
  537         cpu_reset_real();
  538 }
  539 #endif
  540 
  541 void
  542 cpu_reset()
  543 {
  544 #ifdef XBOX
  545         if (arch_i386_is_xbox) {
  546                 /* Kick the PIC16L, it can reboot the box */
  547                 pic16l_reboot();
  548                 for (;;);
  549         }
  550 #endif
  551 
  552 #ifdef SMP
  553         u_int cnt, map;
  554 
  555         if (smp_active) {
  556                 map = PCPU_GET(other_cpus) & ~stopped_cpus;
  557                 if (map != 0) {
  558                         printf("cpu_reset: Stopping other CPUs\n");
  559                         stop_cpus(map);
  560                 }
  561 
  562                 if (PCPU_GET(cpuid) != 0) {
  563                         cpu_reset_proxyid = PCPU_GET(cpuid);
  564                         cpustop_restartfunc = cpu_reset_proxy;
  565                         cpu_reset_proxy_active = 0;
  566                         printf("cpu_reset: Restarting BSP\n");
  567                         started_cpus = (1<<0);          /* Restart CPU #0 */
  568 
  569                         cnt = 0;
  570                         while (cpu_reset_proxy_active == 0 && cnt < 10000000)
  571                                 cnt++;  /* Wait for BSP to announce restart */
  572                         if (cpu_reset_proxy_active == 0)
  573                                 printf("cpu_reset: Failed to restart BSP\n");
  574                         enable_intr();
  575                         cpu_reset_proxy_active = 2;
  576 
  577                         while (1);
  578                         /* NOTREACHED */
  579                 }
  580 
  581                 DELAY(1000000);
  582         }
  583 #endif
  584         cpu_reset_real();
  585         /* NOTREACHED */
  586 }
  587 
  588 static void
  589 cpu_reset_real()
  590 {
  591 
  592 #ifdef CPU_ELAN
  593         if (elan_mmcr != NULL)
  594                 elan_mmcr->RESCFG = 1;
  595 #endif
  596 
  597         if (cpu == CPU_GEODE1100) {
  598                 /* Attempt Geode's own reset */
  599                 outl(0xcf8, 0x80009044ul);
  600                 outl(0xcfc, 0xf);
  601         }
  602 
  603 #ifdef PC98
  604         /*
  605          * Attempt to do a CPU reset via CPU reset port.
  606          */
  607         disable_intr();
  608         if ((inb(0x35) & 0xa0) != 0xa0) {
  609                 outb(0x37, 0x0f);               /* SHUT0 = 0. */
  610                 outb(0x37, 0x0b);               /* SHUT1 = 0. */
  611         }
  612         outb(0xf0, 0x00);               /* Reset. */
  613 #else
  614 #if !defined(BROKEN_KEYBOARD_RESET)
  615         /*
  616          * Attempt to do a CPU reset via the keyboard controller,
  617          * do not turn off GateA20, as any machine that fails
  618          * to do the reset here would then end up in no man's land.
  619          */
  620         outb(IO_KBD + 4, 0xFE);
  621         DELAY(500000);  /* wait 0.5 sec to see if that did it */
  622         printf("Keyboard reset did not work, attempting CPU shutdown\n");
  623         DELAY(1000000); /* wait 1 sec for printf to complete */
  624 #endif
  625 #endif /* PC98 */
  626 
  627         /* Force a shutdown by unmapping entire address space. */
  628         bzero((caddr_t)PTD, NBPTD);
  629 
  630         /* "good night, sweet prince .... <THUNK!>" */
  631         invltlb();
  632         /* NOTREACHED */
  633         while(1);
  634 }
  635 
  636 /*
  637  * Allocate a pool of sf_bufs (sendfile(2) or "super-fast" if you prefer. :-))
  638  */
  639 static void
  640 sf_buf_init(void *arg)
  641 {
  642         struct sf_buf *sf_bufs;
  643         vm_offset_t sf_base;
  644         int i;
  645 
  646         nsfbufs = NSFBUFS;
  647         TUNABLE_INT_FETCH("kern.ipc.nsfbufs", &nsfbufs);
  648 
  649         sf_buf_active = hashinit(nsfbufs, M_TEMP, &sf_buf_hashmask);
  650         TAILQ_INIT(&sf_buf_freelist);
  651         sf_base = kmem_alloc_nofault(kernel_map, nsfbufs * PAGE_SIZE);
  652         sf_bufs = malloc(nsfbufs * sizeof(struct sf_buf), M_TEMP,
  653             M_NOWAIT | M_ZERO);
  654         for (i = 0; i < nsfbufs; i++) {
  655                 sf_bufs[i].kva = sf_base + i * PAGE_SIZE;
  656                 TAILQ_INSERT_TAIL(&sf_buf_freelist, &sf_bufs[i], free_entry);
  657         }
  658         sf_buf_alloc_want = 0;
  659         mtx_init(&sf_buf_lock, "sf_buf", NULL, MTX_DEF);
  660 }
  661 
  662 /*
  663  * Get an sf_buf from the freelist. Will block if none are available.
  664  */
  665 struct sf_buf *
  666 sf_buf_alloc(struct vm_page *m, int flags)
  667 {
  668         pt_entry_t opte, *ptep;
  669         struct sf_head *hash_list;
  670         struct sf_buf *sf;
  671 #ifdef SMP
  672         cpumask_t cpumask, other_cpus;
  673 #endif
  674         int error;
  675 
  676         KASSERT(curthread->td_pinned > 0 || (flags & SFB_CPUPRIVATE) == 0,
  677             ("sf_buf_alloc(SFB_CPUPRIVATE): curthread not pinned"));
  678         hash_list = &sf_buf_active[SF_BUF_HASH(m)];
  679         mtx_lock(&sf_buf_lock);
  680         LIST_FOREACH(sf, hash_list, list_entry) {
  681                 if (sf->m == m) {
  682                         sf->ref_count++;
  683                         if (sf->ref_count == 1) {
  684                                 TAILQ_REMOVE(&sf_buf_freelist, sf, free_entry);
  685                                 nsfbufsused++;
  686                                 nsfbufspeak = imax(nsfbufspeak, nsfbufsused);
  687                         }
  688 #ifdef SMP
  689                         goto shootdown; 
  690 #else
  691                         goto done;
  692 #endif
  693                 }
  694         }
  695         while ((sf = TAILQ_FIRST(&sf_buf_freelist)) == NULL) {
  696                 if (flags & SFB_NOWAIT)
  697                         goto done;
  698                 sf_buf_alloc_want++;
  699                 mbstat.sf_allocwait++;
  700                 error = msleep(&sf_buf_freelist, &sf_buf_lock,
  701                     (flags & SFB_CATCH) ? PCATCH | PVM : PVM, "sfbufa", 0);
  702                 sf_buf_alloc_want--;
  703 
  704                 /*
  705                  * If we got a signal, don't risk going back to sleep. 
  706                  */
  707                 if (error)
  708                         goto done;
  709         }
  710         TAILQ_REMOVE(&sf_buf_freelist, sf, free_entry);
  711         if (sf->m != NULL)
  712                 LIST_REMOVE(sf, list_entry);
  713         LIST_INSERT_HEAD(hash_list, sf, list_entry);
  714         sf->ref_count = 1;
  715         sf->m = m;
  716         nsfbufsused++;
  717         nsfbufspeak = imax(nsfbufspeak, nsfbufsused);
  718 
  719         /*
  720          * Update the sf_buf's virtual-to-physical mapping, flushing the
  721          * virtual address from the TLB.  Since the reference count for 
  722          * the sf_buf's old mapping was zero, that mapping is not 
  723          * currently in use.  Consequently, there is no need to exchange 
  724          * the old and new PTEs atomically, even under PAE.
  725          */
  726         ptep = vtopte(sf->kva);
  727         opte = *ptep;
  728         *ptep = VM_PAGE_TO_PHYS(m) | pgeflag | PG_RW | PG_V;
  729 
  730         /*
  731          * Avoid unnecessary TLB invalidations: If the sf_buf's old
  732          * virtual-to-physical mapping was not used, then any processor
  733          * that has invalidated the sf_buf's virtual address from its TLB
  734          * since the last used mapping need not invalidate again.
  735          */
  736 #ifdef SMP
  737         if ((opte & (PG_V | PG_A)) ==  (PG_V | PG_A))
  738                 sf->cpumask = 0;
  739 shootdown:
  740         sched_pin();
  741         cpumask = PCPU_GET(cpumask);
  742         if ((sf->cpumask & cpumask) == 0) {
  743                 sf->cpumask |= cpumask;
  744                 invlpg(sf->kva);
  745         }
  746         if ((flags & SFB_CPUPRIVATE) == 0) {
  747                 other_cpus = PCPU_GET(other_cpus) & ~sf->cpumask;
  748                 if (other_cpus != 0) {
  749                         sf->cpumask |= other_cpus;
  750                         mtx_lock_spin(&smp_ipi_mtx);
  751                         smp_masked_invlpg(other_cpus, sf->kva);
  752                         mtx_unlock_spin(&smp_ipi_mtx);
  753                 }
  754         }
  755         sched_unpin();  
  756 #else
  757         if ((opte & (PG_V | PG_A)) ==  (PG_V | PG_A))
  758                 pmap_invalidate_page(kernel_pmap, sf->kva);
  759 #endif
  760 done:
  761         mtx_unlock(&sf_buf_lock);
  762         return (sf);
  763 }
  764 
  765 /*
  766  * Remove a reference from the given sf_buf, adding it to the free
  767  * list when its reference count reaches zero.  A freed sf_buf still,
  768  * however, retains its virtual-to-physical mapping until it is
  769  * recycled or reactivated by sf_buf_alloc(9).
  770  */
  771 void
  772 sf_buf_free(struct sf_buf *sf)
  773 {
  774 
  775         mtx_lock(&sf_buf_lock);
  776         sf->ref_count--;
  777         if (sf->ref_count == 0) {
  778                 TAILQ_INSERT_TAIL(&sf_buf_freelist, sf, free_entry);
  779                 nsfbufsused--;
  780                 if (sf_buf_alloc_want > 0)
  781                         wakeup_one(&sf_buf_freelist);
  782         }
  783         mtx_unlock(&sf_buf_lock);
  784 }
  785 
  786 /*
  787  * Software interrupt handler for queued VM system processing.
  788  */   
  789 void  
  790 swi_vm(void *dummy) 
  791 {     
  792         if (busdma_swi_pending != 0)
  793                 busdma_swi();
  794 }
  795 
  796 /*
  797  * Tell whether this address is in some physical memory region.
  798  * Currently used by the kernel coredump code in order to avoid
  799  * dumping the ``ISA memory hole'' which could cause indefinite hangs,
  800  * or other unpredictable behaviour.
  801  */
  802 
  803 int
  804 is_physical_memory(vm_paddr_t addr)
  805 {
  806 
  807 #ifdef DEV_ISA
  808         /* The ISA ``memory hole''. */
  809         if (addr >= 0xa0000 && addr < 0x100000)
  810                 return 0;
  811 #endif
  812 
  813         /*
  814          * stuff other tests for known memory-mapped devices (PCI?)
  815          * here
  816          */
  817 
  818         return 1;
  819 }

Cache object: 1a67e38995a2fc96c67832cc9bca8038


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]


This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.