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: stable/9/sys/i386/i386/vm_machdep.c 264148 2014-04-05 14:24:45Z kib $");
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/kernel.h>
57 #include <sys/ktr.h>
58 #include <sys/lock.h>
59 #include <sys/malloc.h>
60 #include <sys/mbuf.h>
61 #include <sys/mutex.h>
62 #include <sys/pioctl.h>
63 #include <sys/proc.h>
64 #include <sys/sysent.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 XEN
93 #include <xen/hypervisor.h>
94 #endif
95 #ifdef PC98
96 #include <pc98/cbus/cbus.h>
97 #else
98 #include <x86/isa/isa.h>
99 #endif
100
101 #ifdef XBOX
102 #include <machine/xbox.h>
103 #endif
104
105 #ifndef NSFBUFS
106 #define NSFBUFS (512 + maxusers * 16)
107 #endif
108
109 CTASSERT((struct thread **)OFFSETOF_CURTHREAD ==
110 &((struct pcpu *)NULL)->pc_curthread);
111 CTASSERT((struct pcb **)OFFSETOF_CURPCB == &((struct pcpu *)NULL)->pc_curpcb);
112
113 static void cpu_reset_real(void);
114 #ifdef SMP
115 static void cpu_reset_proxy(void);
116 static u_int cpu_reset_proxyid;
117 static volatile u_int cpu_reset_proxy_active;
118 #endif
119 static void sf_buf_init(void *arg);
120 SYSINIT(sock_sf, SI_SUB_MBUF, SI_ORDER_ANY, sf_buf_init, NULL);
121
122 LIST_HEAD(sf_head, sf_buf);
123
124 /*
125 * A hash table of active sendfile(2) buffers
126 */
127 static struct sf_head *sf_buf_active;
128 static u_long sf_buf_hashmask;
129
130 #define SF_BUF_HASH(m) (((m) - vm_page_array) & sf_buf_hashmask)
131
132 static TAILQ_HEAD(, sf_buf) sf_buf_freelist;
133 static u_int sf_buf_alloc_want;
134
135 /*
136 * A lock used to synchronize access to the hash table and free list
137 */
138 static struct mtx sf_buf_lock;
139
140 extern int _ucodesel, _udatasel;
141
142 /*
143 * Finish a fork operation, with process p2 nearly set up.
144 * Copy and update the pcb, set up the stack so that the child
145 * ready to run and return to user mode.
146 */
147 void
cpu_fork(td1,p2,td2,flags)148 cpu_fork(td1, p2, td2, flags)
149 register struct thread *td1;
150 register struct proc *p2;
151 struct thread *td2;
152 int flags;
153 {
154 register struct proc *p1;
155 struct pcb *pcb2;
156 struct mdproc *mdp2;
157
158 p1 = td1->td_proc;
159 if ((flags & RFPROC) == 0) {
160 if ((flags & RFMEM) == 0) {
161 /* unshare user LDT */
162 struct mdproc *mdp1 = &p1->p_md;
163 struct proc_ldt *pldt, *pldt1;
164
165 mtx_lock_spin(&dt_lock);
166 if ((pldt1 = mdp1->md_ldt) != NULL &&
167 pldt1->ldt_refcnt > 1) {
168 pldt = user_ldt_alloc(mdp1, pldt1->ldt_len);
169 if (pldt == NULL)
170 panic("could not copy LDT");
171 mdp1->md_ldt = pldt;
172 set_user_ldt(mdp1);
173 user_ldt_deref(pldt1);
174 } else
175 mtx_unlock_spin(&dt_lock);
176 }
177 return;
178 }
179
180 /* Ensure that td1's pcb is up to date. */
181 if (td1 == curthread)
182 td1->td_pcb->pcb_gs = rgs();
183 #ifdef DEV_NPX
184 critical_enter();
185 if (PCPU_GET(fpcurthread) == td1)
186 npxsave(td1->td_pcb->pcb_save);
187 critical_exit();
188 #endif
189
190 /* Point the pcb to the top of the stack */
191 pcb2 = (struct pcb *)(td2->td_kstack +
192 td2->td_kstack_pages * PAGE_SIZE) - 1;
193 td2->td_pcb = pcb2;
194
195 /* Copy td1's pcb */
196 bcopy(td1->td_pcb, pcb2, sizeof(*pcb2));
197
198 /* Properly initialize pcb_save */
199 pcb2->pcb_save = &pcb2->pcb_user_save;
200
201 /* Point mdproc and then copy over td1's contents */
202 mdp2 = &p2->p_md;
203 bcopy(&p1->p_md, mdp2, sizeof(*mdp2));
204
205 /*
206 * Create a new fresh stack for the new process.
207 * Copy the trap frame for the return to user mode as if from a
208 * syscall. This copies most of the user mode register values.
209 * The -16 is so we can expand the trapframe if we go to vm86.
210 */
211 td2->td_frame = (struct trapframe *)((caddr_t)td2->td_pcb - 16) - 1;
212 bcopy(td1->td_frame, td2->td_frame, sizeof(struct trapframe));
213
214 td2->td_frame->tf_eax = 0; /* Child returns zero */
215 td2->td_frame->tf_eflags &= ~PSL_C; /* success */
216 td2->td_frame->tf_edx = 1;
217
218 /*
219 * If the parent process has the trap bit set (i.e. a debugger had
220 * single stepped the process to the system call), we need to clear
221 * the trap flag from the new frame unless the debugger had set PF_FORK
222 * on the parent. Otherwise, the child will receive a (likely
223 * unexpected) SIGTRAP when it executes the first instruction after
224 * returning to userland.
225 */
226 if ((p1->p_pfsflags & PF_FORK) == 0)
227 td2->td_frame->tf_eflags &= ~PSL_T;
228
229 /*
230 * Set registers for trampoline to user mode. Leave space for the
231 * return address on stack. These are the kernel mode register values.
232 */
233 #ifdef PAE
234 pcb2->pcb_cr3 = vtophys(vmspace_pmap(p2->p_vmspace)->pm_pdpt);
235 #else
236 pcb2->pcb_cr3 = vtophys(vmspace_pmap(p2->p_vmspace)->pm_pdir);
237 #endif
238 pcb2->pcb_edi = 0;
239 pcb2->pcb_esi = (int)fork_return; /* fork_trampoline argument */
240 pcb2->pcb_ebp = 0;
241 pcb2->pcb_esp = (int)td2->td_frame - sizeof(void *);
242 pcb2->pcb_ebx = (int)td2; /* fork_trampoline argument */
243 pcb2->pcb_eip = (int)fork_trampoline;
244 pcb2->pcb_psl = PSL_KERNEL; /* ints disabled */
245 /*-
246 * pcb2->pcb_dr*: cloned above.
247 * pcb2->pcb_savefpu: cloned above.
248 * pcb2->pcb_flags: cloned above.
249 * pcb2->pcb_onfault: cloned above (always NULL here?).
250 * pcb2->pcb_gs: cloned above.
251 * pcb2->pcb_ext: cleared below.
252 */
253
254 /*
255 * XXX don't copy the i/o pages. this should probably be fixed.
256 */
257 pcb2->pcb_ext = 0;
258
259 /* Copy the LDT, if necessary. */
260 mtx_lock_spin(&dt_lock);
261 if (mdp2->md_ldt != NULL) {
262 if (flags & RFMEM) {
263 mdp2->md_ldt->ldt_refcnt++;
264 } else {
265 mdp2->md_ldt = user_ldt_alloc(mdp2,
266 mdp2->md_ldt->ldt_len);
267 if (mdp2->md_ldt == NULL)
268 panic("could not copy LDT");
269 }
270 }
271 mtx_unlock_spin(&dt_lock);
272
273 /* Setup to release spin count in fork_exit(). */
274 td2->td_md.md_spinlock_count = 1;
275 /*
276 * XXX XEN need to check on PSL_USER is handled
277 */
278 td2->td_md.md_saved_flags = PSL_KERNEL | PSL_I;
279 /*
280 * Now, cpu_switch() can schedule the new process.
281 * pcb_esp is loaded pointing to the cpu_switch() stack frame
282 * containing the return address when exiting cpu_switch.
283 * This will normally be to fork_trampoline(), which will have
284 * %ebx loaded with the new proc's pointer. fork_trampoline()
285 * will set up a stack to call fork_return(p, frame); to complete
286 * the return to user-mode.
287 */
288 }
289
290 /*
291 * Intercept the return address from a freshly forked process that has NOT
292 * been scheduled yet.
293 *
294 * This is needed to make kernel threads stay in kernel mode.
295 */
296 void
cpu_set_fork_handler(td,func,arg)297 cpu_set_fork_handler(td, func, arg)
298 struct thread *td;
299 void (*func)(void *);
300 void *arg;
301 {
302 /*
303 * Note that the trap frame follows the args, so the function
304 * is really called like this: func(arg, frame);
305 */
306 td->td_pcb->pcb_esi = (int) func; /* function */
307 td->td_pcb->pcb_ebx = (int) arg; /* first arg */
308 }
309
310 void
cpu_exit(struct thread * td)311 cpu_exit(struct thread *td)
312 {
313
314 /*
315 * If this process has a custom LDT, release it. Reset pc->pcb_gs
316 * and %gs before we free it in case they refer to an LDT entry.
317 */
318 mtx_lock_spin(&dt_lock);
319 if (td->td_proc->p_md.md_ldt) {
320 td->td_pcb->pcb_gs = _udatasel;
321 load_gs(_udatasel);
322 user_ldt_free(td);
323 } else
324 mtx_unlock_spin(&dt_lock);
325 }
326
327 void
cpu_thread_exit(struct thread * td)328 cpu_thread_exit(struct thread *td)
329 {
330
331 #ifdef DEV_NPX
332 critical_enter();
333 if (td == PCPU_GET(fpcurthread))
334 npxdrop();
335 critical_exit();
336 #endif
337
338 /* Disable any hardware breakpoints. */
339 if (td->td_pcb->pcb_flags & PCB_DBREGS) {
340 reset_dbregs();
341 td->td_pcb->pcb_flags &= ~PCB_DBREGS;
342 }
343 }
344
345 void
cpu_thread_clean(struct thread * td)346 cpu_thread_clean(struct thread *td)
347 {
348 struct pcb *pcb;
349
350 pcb = td->td_pcb;
351 if (pcb->pcb_ext != NULL) {
352 /* if (pcb->pcb_ext->ext_refcount-- == 1) ?? */
353 /*
354 * XXX do we need to move the TSS off the allocated pages
355 * before freeing them? (not done here)
356 */
357 kmem_free(kernel_map, (vm_offset_t)pcb->pcb_ext,
358 ctob(IOPAGES + 1));
359 pcb->pcb_ext = NULL;
360 }
361 }
362
363 void
cpu_thread_swapin(struct thread * td)364 cpu_thread_swapin(struct thread *td)
365 {
366 }
367
368 void
cpu_thread_swapout(struct thread * td)369 cpu_thread_swapout(struct thread *td)
370 {
371 }
372
373 void
cpu_thread_alloc(struct thread * td)374 cpu_thread_alloc(struct thread *td)
375 {
376
377 td->td_pcb = (struct pcb *)(td->td_kstack +
378 td->td_kstack_pages * PAGE_SIZE) - 1;
379 td->td_frame = (struct trapframe *)((caddr_t)td->td_pcb - 16) - 1;
380 td->td_pcb->pcb_ext = NULL;
381 td->td_pcb->pcb_save = &td->td_pcb->pcb_user_save;
382 }
383
384 void
cpu_thread_free(struct thread * td)385 cpu_thread_free(struct thread *td)
386 {
387
388 cpu_thread_clean(td);
389 }
390
391 void
cpu_set_syscall_retval(struct thread * td,int error)392 cpu_set_syscall_retval(struct thread *td, int error)
393 {
394
395 switch (error) {
396 case 0:
397 td->td_frame->tf_eax = td->td_retval[0];
398 td->td_frame->tf_edx = td->td_retval[1];
399 td->td_frame->tf_eflags &= ~PSL_C;
400 break;
401
402 case ERESTART:
403 /*
404 * Reconstruct pc, assuming lcall $X,y is 7 bytes, int
405 * 0x80 is 2 bytes. We saved this in tf_err.
406 */
407 td->td_frame->tf_eip -= td->td_frame->tf_err;
408 break;
409
410 case EJUSTRETURN:
411 break;
412
413 default:
414 if (td->td_proc->p_sysent->sv_errsize) {
415 if (error >= td->td_proc->p_sysent->sv_errsize)
416 error = -1; /* XXX */
417 else
418 error = td->td_proc->p_sysent->sv_errtbl[error];
419 }
420 td->td_frame->tf_eax = error;
421 td->td_frame->tf_eflags |= PSL_C;
422 break;
423 }
424 }
425
426 /*
427 * Initialize machine state (pcb and trap frame) for a new thread about to
428 * upcall. Put enough state in the new thread's PCB to get it to go back
429 * userret(), where we can intercept it again to set the return (upcall)
430 * Address and stack, along with those from upcals that are from other sources
431 * such as those generated in thread_userret() itself.
432 */
433 void
cpu_set_upcall(struct thread * td,struct thread * td0)434 cpu_set_upcall(struct thread *td, struct thread *td0)
435 {
436 struct pcb *pcb2;
437
438 /* Point the pcb to the top of the stack. */
439 pcb2 = td->td_pcb;
440
441 /*
442 * Copy the upcall pcb. This loads kernel regs.
443 * Those not loaded individually below get their default
444 * values here.
445 */
446 bcopy(td0->td_pcb, pcb2, sizeof(*pcb2));
447 pcb2->pcb_flags &= ~(PCB_NPXINITDONE | PCB_NPXUSERINITDONE |
448 PCB_KERNNPX);
449 pcb2->pcb_save = &pcb2->pcb_user_save;
450
451 /*
452 * Create a new fresh stack for the new thread.
453 */
454 bcopy(td0->td_frame, td->td_frame, sizeof(struct trapframe));
455
456 /* If the current thread has the trap bit set (i.e. a debugger had
457 * single stepped the process to the system call), we need to clear
458 * the trap flag from the new frame. Otherwise, the new thread will
459 * receive a (likely unexpected) SIGTRAP when it executes the first
460 * instruction after returning to userland.
461 */
462 td->td_frame->tf_eflags &= ~PSL_T;
463
464 /*
465 * Set registers for trampoline to user mode. Leave space for the
466 * return address on stack. These are the kernel mode register values.
467 */
468 pcb2->pcb_edi = 0;
469 pcb2->pcb_esi = (int)fork_return; /* trampoline arg */
470 pcb2->pcb_ebp = 0;
471 pcb2->pcb_esp = (int)td->td_frame - sizeof(void *); /* trampoline arg */
472 pcb2->pcb_ebx = (int)td; /* trampoline arg */
473 pcb2->pcb_eip = (int)fork_trampoline;
474 pcb2->pcb_psl &= ~(PSL_I); /* interrupts must be disabled */
475 pcb2->pcb_gs = rgs();
476 /*
477 * If we didn't copy the pcb, we'd need to do the following registers:
478 * pcb2->pcb_cr3: cloned above.
479 * pcb2->pcb_dr*: cloned above.
480 * pcb2->pcb_savefpu: cloned above.
481 * pcb2->pcb_flags: cloned above.
482 * pcb2->pcb_onfault: cloned above (always NULL here?).
483 * pcb2->pcb_gs: cloned above.
484 * pcb2->pcb_ext: cleared below.
485 */
486 pcb2->pcb_ext = NULL;
487
488 /* Setup to release spin count in fork_exit(). */
489 td->td_md.md_spinlock_count = 1;
490 td->td_md.md_saved_flags = PSL_KERNEL | PSL_I;
491 }
492
493 /*
494 * Set that machine state for performing an upcall that has to
495 * be done in thread_userret() so that those upcalls generated
496 * in thread_userret() itself can be done as well.
497 */
498 void
cpu_set_upcall_kse(struct thread * td,void (* entry)(void *),void * arg,stack_t * stack)499 cpu_set_upcall_kse(struct thread *td, void (*entry)(void *), void *arg,
500 stack_t *stack)
501 {
502
503 /*
504 * Do any extra cleaning that needs to be done.
505 * The thread may have optional components
506 * that are not present in a fresh thread.
507 * This may be a recycled thread so make it look
508 * as though it's newly allocated.
509 */
510 cpu_thread_clean(td);
511
512 /*
513 * Set the trap frame to point at the beginning of the uts
514 * function.
515 */
516 td->td_frame->tf_ebp = 0;
517 td->td_frame->tf_esp =
518 (((int)stack->ss_sp + stack->ss_size - 4) & ~0x0f) - 4;
519 td->td_frame->tf_eip = (int)entry;
520
521 /*
522 * Pass the address of the mailbox for this kse to the uts
523 * function as a parameter on the stack.
524 */
525 suword((void *)(td->td_frame->tf_esp + sizeof(void *)),
526 (int)arg);
527 }
528
529 int
cpu_set_user_tls(struct thread * td,void * tls_base)530 cpu_set_user_tls(struct thread *td, void *tls_base)
531 {
532 struct segment_descriptor sd;
533 uint32_t base;
534
535 /*
536 * Construct a descriptor and store it in the pcb for
537 * the next context switch. Also store it in the gdt
538 * so that the load of tf_fs into %fs will activate it
539 * at return to userland.
540 */
541 base = (uint32_t)tls_base;
542 sd.sd_lobase = base & 0xffffff;
543 sd.sd_hibase = (base >> 24) & 0xff;
544 sd.sd_lolimit = 0xffff; /* 4GB limit, wraps around */
545 sd.sd_hilimit = 0xf;
546 sd.sd_type = SDT_MEMRWA;
547 sd.sd_dpl = SEL_UPL;
548 sd.sd_p = 1;
549 sd.sd_xx = 0;
550 sd.sd_def32 = 1;
551 sd.sd_gran = 1;
552 critical_enter();
553 /* set %gs */
554 td->td_pcb->pcb_gsd = sd;
555 if (td == curthread) {
556 PCPU_GET(fsgs_gdt)[1] = sd;
557 load_gs(GSEL(GUGS_SEL, SEL_UPL));
558 }
559 critical_exit();
560 return (0);
561 }
562
563 /*
564 * Convert kernel VA to physical address
565 */
566 vm_paddr_t
kvtop(void * addr)567 kvtop(void *addr)
568 {
569 vm_paddr_t pa;
570
571 pa = pmap_kextract((vm_offset_t)addr);
572 if (pa == 0)
573 panic("kvtop: zero page frame");
574 return (pa);
575 }
576
577 #ifdef SMP
578 static void
cpu_reset_proxy()579 cpu_reset_proxy()
580 {
581 cpuset_t tcrp;
582
583 cpu_reset_proxy_active = 1;
584 while (cpu_reset_proxy_active == 1)
585 ; /* Wait for other cpu to see that we've started */
586 CPU_SETOF(cpu_reset_proxyid, &tcrp);
587 stop_cpus(tcrp);
588 printf("cpu_reset_proxy: Stopped CPU %d\n", cpu_reset_proxyid);
589 DELAY(1000000);
590 cpu_reset_real();
591 }
592 #endif
593
594 void
cpu_reset()595 cpu_reset()
596 {
597 #ifdef XBOX
598 if (arch_i386_is_xbox) {
599 /* Kick the PIC16L, it can reboot the box */
600 pic16l_reboot();
601 for (;;);
602 }
603 #endif
604
605 #ifdef SMP
606 cpuset_t map;
607 u_int cnt;
608
609 if (smp_active) {
610 map = all_cpus;
611 CPU_CLR(PCPU_GET(cpuid), &map);
612 CPU_NAND(&map, &stopped_cpus);
613 if (!CPU_EMPTY(&map)) {
614 printf("cpu_reset: Stopping other CPUs\n");
615 stop_cpus(map);
616 }
617
618 if (PCPU_GET(cpuid) != 0) {
619 cpu_reset_proxyid = PCPU_GET(cpuid);
620 cpustop_restartfunc = cpu_reset_proxy;
621 cpu_reset_proxy_active = 0;
622 printf("cpu_reset: Restarting BSP\n");
623
624 /* Restart CPU #0. */
625 /* XXX: restart_cpus(1 << 0); */
626 CPU_SETOF(0, &started_cpus);
627 wmb();
628
629 cnt = 0;
630 while (cpu_reset_proxy_active == 0 && cnt < 10000000)
631 cnt++; /* Wait for BSP to announce restart */
632 if (cpu_reset_proxy_active == 0)
633 printf("cpu_reset: Failed to restart BSP\n");
634 enable_intr();
635 cpu_reset_proxy_active = 2;
636
637 while (1);
638 /* NOTREACHED */
639 }
640
641 DELAY(1000000);
642 }
643 #endif
644 cpu_reset_real();
645 /* NOTREACHED */
646 }
647
648 static void
cpu_reset_real()649 cpu_reset_real()
650 {
651 struct region_descriptor null_idt;
652 #ifndef PC98
653 int b;
654 #endif
655
656 disable_intr();
657 #ifdef XEN
658 if (smp_processor_id() == 0)
659 HYPERVISOR_shutdown(SHUTDOWN_reboot);
660 else
661 HYPERVISOR_shutdown(SHUTDOWN_poweroff);
662 #endif
663 #ifdef CPU_ELAN
664 if (elan_mmcr != NULL)
665 elan_mmcr->RESCFG = 1;
666 #endif
667
668 if (cpu == CPU_GEODE1100) {
669 /* Attempt Geode's own reset */
670 outl(0xcf8, 0x80009044ul);
671 outl(0xcfc, 0xf);
672 }
673
674 #ifdef PC98
675 /*
676 * Attempt to do a CPU reset via CPU reset port.
677 */
678 if ((inb(0x35) & 0xa0) != 0xa0) {
679 outb(0x37, 0x0f); /* SHUT0 = 0. */
680 outb(0x37, 0x0b); /* SHUT1 = 0. */
681 }
682 outb(0xf0, 0x00); /* Reset. */
683 #else
684 #if !defined(BROKEN_KEYBOARD_RESET)
685 /*
686 * Attempt to do a CPU reset via the keyboard controller,
687 * do not turn off GateA20, as any machine that fails
688 * to do the reset here would then end up in no man's land.
689 */
690 outb(IO_KBD + 4, 0xFE);
691 DELAY(500000); /* wait 0.5 sec to see if that did it */
692 #endif
693
694 /*
695 * Attempt to force a reset via the Reset Control register at
696 * I/O port 0xcf9. Bit 2 forces a system reset when it
697 * transitions from 0 to 1. Bit 1 selects the type of reset
698 * to attempt: 0 selects a "soft" reset, and 1 selects a
699 * "hard" reset. We try a "hard" reset. The first write sets
700 * bit 1 to select a "hard" reset and clears bit 2. The
701 * second write forces a 0 -> 1 transition in bit 2 to trigger
702 * a reset.
703 */
704 outb(0xcf9, 0x2);
705 outb(0xcf9, 0x6);
706 DELAY(500000); /* wait 0.5 sec to see if that did it */
707
708 /*
709 * Attempt to force a reset via the Fast A20 and Init register
710 * at I/O port 0x92. Bit 1 serves as an alternate A20 gate.
711 * Bit 0 asserts INIT# when set to 1. We are careful to only
712 * preserve bit 1 while setting bit 0. We also must clear bit
713 * 0 before setting it if it isn't already clear.
714 */
715 b = inb(0x92);
716 if (b != 0xff) {
717 if ((b & 0x1) != 0)
718 outb(0x92, b & 0xfe);
719 outb(0x92, b | 0x1);
720 DELAY(500000); /* wait 0.5 sec to see if that did it */
721 }
722 #endif /* PC98 */
723
724 printf("No known reset method worked, attempting CPU shutdown\n");
725 DELAY(1000000); /* wait 1 sec for printf to complete */
726
727 /* Wipe the IDT. */
728 null_idt.rd_limit = 0;
729 null_idt.rd_base = 0;
730 lidt(&null_idt);
731
732 /* "good night, sweet prince .... <THUNK!>" */
733 breakpoint();
734
735 /* NOTREACHED */
736 while(1);
737 }
738
739 /*
740 * Allocate a pool of sf_bufs (sendfile(2) or "super-fast" if you prefer. :-))
741 */
742 static void
sf_buf_init(void * arg)743 sf_buf_init(void *arg)
744 {
745 struct sf_buf *sf_bufs;
746 vm_offset_t sf_base;
747 int i;
748
749 nsfbufs = NSFBUFS;
750 TUNABLE_INT_FETCH("kern.ipc.nsfbufs", &nsfbufs);
751
752 sf_buf_active = hashinit(nsfbufs, M_TEMP, &sf_buf_hashmask);
753 TAILQ_INIT(&sf_buf_freelist);
754 sf_base = kmem_alloc_nofault(kernel_map, nsfbufs * PAGE_SIZE);
755 sf_bufs = malloc(nsfbufs * sizeof(struct sf_buf), M_TEMP,
756 M_NOWAIT | M_ZERO);
757 for (i = 0; i < nsfbufs; i++) {
758 sf_bufs[i].kva = sf_base + i * PAGE_SIZE;
759 TAILQ_INSERT_TAIL(&sf_buf_freelist, &sf_bufs[i], free_entry);
760 }
761 sf_buf_alloc_want = 0;
762 mtx_init(&sf_buf_lock, "sf_buf", NULL, MTX_DEF);
763 }
764
765 /*
766 * Invalidate the cache lines that may belong to the page, if
767 * (possibly old) mapping of the page by sf buffer exists. Returns
768 * TRUE when mapping was found and cache invalidated.
769 */
770 boolean_t
sf_buf_invalidate_cache(vm_page_t m)771 sf_buf_invalidate_cache(vm_page_t m)
772 {
773 struct sf_head *hash_list;
774 struct sf_buf *sf;
775 boolean_t ret;
776
777 hash_list = &sf_buf_active[SF_BUF_HASH(m)];
778 ret = FALSE;
779 mtx_lock(&sf_buf_lock);
780 LIST_FOREACH(sf, hash_list, list_entry) {
781 if (sf->m == m) {
782 /*
783 * Use pmap_qenter to update the pte for
784 * existing mapping, in particular, the PAT
785 * settings are recalculated.
786 */
787 pmap_qenter(sf->kva, &m, 1);
788 pmap_invalidate_cache_range(sf->kva, sf->kva +
789 PAGE_SIZE);
790 ret = TRUE;
791 break;
792 }
793 }
794 mtx_unlock(&sf_buf_lock);
795 return (ret);
796 }
797
798 /*
799 * Get an sf_buf from the freelist. May block if none are available.
800 */
801 struct sf_buf *
sf_buf_alloc(struct vm_page * m,int flags)802 sf_buf_alloc(struct vm_page *m, int flags)
803 {
804 pt_entry_t opte, *ptep;
805 struct sf_head *hash_list;
806 struct sf_buf *sf;
807 #ifdef SMP
808 cpuset_t other_cpus;
809 u_int cpuid;
810 #endif
811 int error;
812
813 KASSERT(curthread->td_pinned > 0 || (flags & SFB_CPUPRIVATE) == 0,
814 ("sf_buf_alloc(SFB_CPUPRIVATE): curthread not pinned"));
815 hash_list = &sf_buf_active[SF_BUF_HASH(m)];
816 mtx_lock(&sf_buf_lock);
817 LIST_FOREACH(sf, hash_list, list_entry) {
818 if (sf->m == m) {
819 sf->ref_count++;
820 if (sf->ref_count == 1) {
821 TAILQ_REMOVE(&sf_buf_freelist, sf, free_entry);
822 nsfbufsused++;
823 nsfbufspeak = imax(nsfbufspeak, nsfbufsused);
824 }
825 #ifdef SMP
826 goto shootdown;
827 #else
828 goto done;
829 #endif
830 }
831 }
832 while ((sf = TAILQ_FIRST(&sf_buf_freelist)) == NULL) {
833 if (flags & SFB_NOWAIT)
834 goto done;
835 sf_buf_alloc_want++;
836 mbstat.sf_allocwait++;
837 error = msleep(&sf_buf_freelist, &sf_buf_lock,
838 (flags & SFB_CATCH) ? PCATCH | PVM : PVM, "sfbufa", 0);
839 sf_buf_alloc_want--;
840
841 /*
842 * If we got a signal, don't risk going back to sleep.
843 */
844 if (error)
845 goto done;
846 }
847 TAILQ_REMOVE(&sf_buf_freelist, sf, free_entry);
848 if (sf->m != NULL)
849 LIST_REMOVE(sf, list_entry);
850 LIST_INSERT_HEAD(hash_list, sf, list_entry);
851 sf->ref_count = 1;
852 sf->m = m;
853 nsfbufsused++;
854 nsfbufspeak = imax(nsfbufspeak, nsfbufsused);
855
856 /*
857 * Update the sf_buf's virtual-to-physical mapping, flushing the
858 * virtual address from the TLB. Since the reference count for
859 * the sf_buf's old mapping was zero, that mapping is not
860 * currently in use. Consequently, there is no need to exchange
861 * the old and new PTEs atomically, even under PAE.
862 */
863 ptep = vtopte(sf->kva);
864 opte = *ptep;
865 #ifdef XEN
866 PT_SET_MA(sf->kva, xpmap_ptom(VM_PAGE_TO_PHYS(m)) | pgeflag
867 | PG_RW | PG_V | pmap_cache_bits(m->md.pat_mode, 0));
868 #else
869 *ptep = VM_PAGE_TO_PHYS(m) | pgeflag | PG_RW | PG_V |
870 pmap_cache_bits(m->md.pat_mode, 0);
871 #endif
872
873 /*
874 * Avoid unnecessary TLB invalidations: If the sf_buf's old
875 * virtual-to-physical mapping was not used, then any processor
876 * that has invalidated the sf_buf's virtual address from its TLB
877 * since the last used mapping need not invalidate again.
878 */
879 #ifdef SMP
880 if ((opte & (PG_V | PG_A)) == (PG_V | PG_A))
881 CPU_ZERO(&sf->cpumask);
882 shootdown:
883 sched_pin();
884 cpuid = PCPU_GET(cpuid);
885 if (!CPU_ISSET(cpuid, &sf->cpumask)) {
886 CPU_SET(cpuid, &sf->cpumask);
887 invlpg(sf->kva);
888 }
889 if ((flags & SFB_CPUPRIVATE) == 0) {
890 other_cpus = all_cpus;
891 CPU_CLR(cpuid, &other_cpus);
892 CPU_NAND(&other_cpus, &sf->cpumask);
893 if (!CPU_EMPTY(&other_cpus)) {
894 CPU_OR(&sf->cpumask, &other_cpus);
895 smp_masked_invlpg(other_cpus, sf->kva);
896 }
897 }
898 sched_unpin();
899 #else
900 if ((opte & (PG_V | PG_A)) == (PG_V | PG_A))
901 pmap_invalidate_page(kernel_pmap, sf->kva);
902 #endif
903 done:
904 mtx_unlock(&sf_buf_lock);
905 return (sf);
906 }
907
908 /*
909 * Remove a reference from the given sf_buf, adding it to the free
910 * list when its reference count reaches zero. A freed sf_buf still,
911 * however, retains its virtual-to-physical mapping until it is
912 * recycled or reactivated by sf_buf_alloc(9).
913 */
914 void
sf_buf_free(struct sf_buf * sf)915 sf_buf_free(struct sf_buf *sf)
916 {
917
918 mtx_lock(&sf_buf_lock);
919 sf->ref_count--;
920 if (sf->ref_count == 0) {
921 TAILQ_INSERT_TAIL(&sf_buf_freelist, sf, free_entry);
922 nsfbufsused--;
923 #ifdef XEN
924 /*
925 * Xen doesn't like having dangling R/W mappings
926 */
927 pmap_qremove(sf->kva, 1);
928 sf->m = NULL;
929 LIST_REMOVE(sf, list_entry);
930 #endif
931 if (sf_buf_alloc_want > 0)
932 wakeup(&sf_buf_freelist);
933 }
934 mtx_unlock(&sf_buf_lock);
935 }
936
937 /*
938 * Software interrupt handler for queued VM system processing.
939 */
940 void
swi_vm(void * dummy)941 swi_vm(void *dummy)
942 {
943 if (busdma_swi_pending != 0)
944 busdma_swi();
945 }
946
947 /*
948 * Tell whether this address is in some physical memory region.
949 * Currently used by the kernel coredump code in order to avoid
950 * dumping the ``ISA memory hole'' which could cause indefinite hangs,
951 * or other unpredictable behaviour.
952 */
953
954 int
is_physical_memory(vm_paddr_t addr)955 is_physical_memory(vm_paddr_t addr)
956 {
957
958 #ifdef DEV_ISA
959 /* The ISA ``memory hole''. */
960 if (addr >= 0xa0000 && addr < 0x100000)
961 return 0;
962 #endif
963
964 /*
965 * stuff other tests for known memory-mapped devices (PCI?)
966 * here
967 */
968
969 return 1;
970 }
971