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 * $FreeBSD: releng/5.0/sys/i386/i386/vm_machdep.c 107719 2002-12-10 02:33:45Z julian $
42 */
43
44 #include "opt_npx.h"
45 #ifdef PC98
46 #include "opt_pc98.h"
47 #endif
48 #include "opt_reset.h"
49 #include "opt_isa.h"
50 #include "opt_kstack_pages.h"
51
52 #include <sys/param.h>
53 #include <sys/systm.h>
54 #include <sys/malloc.h>
55 #include <sys/proc.h>
56 #include <sys/kse.h>
57 #include <sys/bio.h>
58 #include <sys/buf.h>
59 #include <sys/vnode.h>
60 #include <sys/vmmeter.h>
61 #include <sys/kernel.h>
62 #include <sys/ktr.h>
63 #include <sys/mutex.h>
64 #include <sys/smp.h>
65 #include <sys/sysctl.h>
66 #include <sys/unistd.h>
67
68 #include <machine/cpu.h>
69 #include <machine/md_var.h>
70 #include <machine/pcb.h>
71 #include <machine/pcb_ext.h>
72 #include <machine/vm86.h>
73
74 #include <vm/vm.h>
75 #include <vm/vm_param.h>
76 #include <sys/lock.h>
77 #include <vm/vm_kern.h>
78 #include <vm/vm_page.h>
79 #include <vm/vm_map.h>
80 #include <vm/vm_extern.h>
81
82 #include <sys/user.h>
83
84 #ifdef PC98
85 #include <pc98/pc98/pc98.h>
86 #else
87 #include <i386/isa/isa.h>
88 #endif
89
90 static void cpu_reset_real(void);
91 #ifdef SMP
92 static void cpu_reset_proxy(void);
93 static u_int cpu_reset_proxyid;
94 static volatile u_int cpu_reset_proxy_active;
95 #endif
96 extern int _ucodesel, _udatasel;
97
98 /*
99 * quick version of vm_fault
100 */
101 int
102 vm_fault_quick(v, prot)
103 caddr_t v;
104 int prot;
105 {
106 int r;
107
108 if (prot & VM_PROT_WRITE)
109 r = subyte(v, fubyte(v));
110 else
111 r = fubyte(v);
112 return(r);
113 }
114
115 /*
116 * Finish a fork operation, with process p2 nearly set up.
117 * Copy and update the pcb, set up the stack so that the child
118 * ready to run and return to user mode.
119 */
120 void
121 cpu_fork(td1, p2, td2, flags)
122 register struct thread *td1;
123 register struct proc *p2;
124 struct thread *td2;
125 int flags;
126 {
127 register struct proc *p1;
128 struct pcb *pcb2;
129 struct mdproc *mdp2;
130 #ifdef DEV_NPX
131 register_t savecrit;
132 #endif
133
134 p1 = td1->td_proc;
135 if ((flags & RFPROC) == 0) {
136 if ((flags & RFMEM) == 0) {
137 /* unshare user LDT */
138 struct mdproc *mdp1 = &p1->p_md;
139 struct proc_ldt *pldt = mdp1->md_ldt;
140 if (pldt && pldt->ldt_refcnt > 1) {
141 pldt = user_ldt_alloc(mdp1, pldt->ldt_len);
142 if (pldt == NULL)
143 panic("could not copy LDT");
144 mdp1->md_ldt = pldt;
145 set_user_ldt(mdp1);
146 user_ldt_free(td1);
147 }
148 }
149 return;
150 }
151
152 /* Ensure that p1's pcb is up to date. */
153 #ifdef DEV_NPX
154 if (td1 == curthread)
155 td1->td_pcb->pcb_gs = rgs();
156 savecrit = intr_disable();
157 if (PCPU_GET(fpcurthread) == td1)
158 npxsave(&td1->td_pcb->pcb_save);
159 intr_restore(savecrit);
160 #endif
161
162 /* Point the pcb to the top of the stack */
163 pcb2 = (struct pcb *)(td2->td_kstack + KSTACK_PAGES * PAGE_SIZE) - 1;
164 td2->td_pcb = pcb2;
165
166 /* Copy p1's pcb */
167 bcopy(td1->td_pcb, pcb2, sizeof(*pcb2));
168
169 /* Point mdproc and then copy over td1's contents */
170 mdp2 = &p2->p_md;
171 bcopy(&p1->p_md, mdp2, sizeof(*mdp2));
172
173 /*
174 * Create a new fresh stack for the new process.
175 * Copy the trap frame for the return to user mode as if from a
176 * syscall. This copies most of the user mode register values.
177 * The -16 is so we can expand the trapframe if we go to vm86.
178 */
179 td2->td_frame = (struct trapframe *)((caddr_t)td2->td_pcb - 16) - 1;
180 bcopy(td1->td_frame, td2->td_frame, sizeof(struct trapframe));
181
182 td2->td_frame->tf_eax = 0; /* Child returns zero */
183 td2->td_frame->tf_eflags &= ~PSL_C; /* success */
184 td2->td_frame->tf_edx = 1;
185
186 /*
187 * Set registers for trampoline to user mode. Leave space for the
188 * return address on stack. These are the kernel mode register values.
189 */
190 pcb2->pcb_cr3 = vtophys(vmspace_pmap(p2->p_vmspace)->pm_pdir);
191 pcb2->pcb_edi = 0;
192 pcb2->pcb_esi = (int)fork_return; /* fork_trampoline argument */
193 pcb2->pcb_ebp = 0;
194 pcb2->pcb_esp = (int)td2->td_frame - sizeof(void *);
195 pcb2->pcb_ebx = (int)td2; /* fork_trampoline argument */
196 pcb2->pcb_eip = (int)fork_trampoline;
197 pcb2->pcb_psl = td2->td_frame->tf_eflags & ~PSL_I; /* ints disabled */
198 /*-
199 * pcb2->pcb_dr*: cloned above.
200 * pcb2->pcb_savefpu: cloned above.
201 * pcb2->pcb_flags: cloned above.
202 * pcb2->pcb_onfault: cloned above (always NULL here?).
203 * pcb2->pcb_gs: cloned above.
204 * pcb2->pcb_ext: cleared below.
205 */
206
207 /*
208 * XXX don't copy the i/o pages. this should probably be fixed.
209 */
210 pcb2->pcb_ext = 0;
211
212 /* Copy the LDT, if necessary. */
213 mtx_lock_spin(&sched_lock);
214 if (mdp2->md_ldt != 0) {
215 if (flags & RFMEM) {
216 mdp2->md_ldt->ldt_refcnt++;
217 } else {
218 mdp2->md_ldt = user_ldt_alloc(mdp2,
219 mdp2->md_ldt->ldt_len);
220 if (mdp2->md_ldt == NULL)
221 panic("could not copy LDT");
222 }
223 }
224 mtx_unlock_spin(&sched_lock);
225
226 /*
227 * Now, cpu_switch() can schedule the new process.
228 * pcb_esp is loaded pointing to the cpu_switch() stack frame
229 * containing the return address when exiting cpu_switch.
230 * This will normally be to fork_trampoline(), which will have
231 * %ebx loaded with the new proc's pointer. fork_trampoline()
232 * will set up a stack to call fork_return(p, frame); to complete
233 * the return to user-mode.
234 */
235 }
236
237 /*
238 * Intercept the return address from a freshly forked process that has NOT
239 * been scheduled yet.
240 *
241 * This is needed to make kernel threads stay in kernel mode.
242 */
243 void
244 cpu_set_fork_handler(td, func, arg)
245 struct thread *td;
246 void (*func)(void *);
247 void *arg;
248 {
249 /*
250 * Note that the trap frame follows the args, so the function
251 * is really called like this: func(arg, frame);
252 */
253 td->td_pcb->pcb_esi = (int) func; /* function */
254 td->td_pcb->pcb_ebx = (int) arg; /* first arg */
255 }
256
257 void
258 cpu_exit(struct thread *td)
259 {
260 struct mdproc *mdp;
261
262 mdp = &td->td_proc->p_md;
263 if (mdp->md_ldt)
264 user_ldt_free(td);
265 reset_dbregs();
266 }
267
268 void
269 cpu_thread_exit(struct thread *td)
270 {
271 struct pcb *pcb = td->td_pcb;
272 #ifdef DEV_NPX
273 npxexit(td);
274 #endif
275 if (pcb->pcb_flags & PCB_DBREGS) {
276 /*
277 * disable all hardware breakpoints
278 */
279 reset_dbregs();
280 pcb->pcb_flags &= ~PCB_DBREGS;
281 }
282 }
283
284 void
285 cpu_thread_clean(struct thread *td)
286 {
287 struct pcb *pcb;
288
289 pcb = td->td_pcb;
290 if (pcb->pcb_ext != 0) {
291 /* XXXKSE XXXSMP not SMP SAFE.. what locks do we have? */
292 /* if (pcb->pcb_ext->ext_refcount-- == 1) ?? */
293 /*
294 * XXX do we need to move the TSS off the allocated pages
295 * before freeing them? (not done here)
296 */
297 mtx_lock(&Giant);
298 kmem_free(kernel_map, (vm_offset_t)pcb->pcb_ext,
299 ctob(IOPAGES + 1));
300 mtx_unlock(&Giant);
301 pcb->pcb_ext = 0;
302 }
303 }
304
305 void
306 cpu_sched_exit(td)
307 register struct thread *td;
308 {
309 }
310
311 void
312 cpu_thread_setup(struct thread *td)
313 {
314
315 td->td_pcb =
316 (struct pcb *)(td->td_kstack + KSTACK_PAGES * PAGE_SIZE) - 1;
317 td->td_frame = (struct trapframe *)((caddr_t)td->td_pcb - 16) - 1;
318 }
319
320 /*
321 * Initialize machine state (pcb and trap frame) for a new thread about to
322 * upcall. Pu t enough state in the new thread's PCB to get it to go back
323 * userret(), where we can intercept it again to set the return (upcall)
324 * Address and stack, along with those from upcals that are from other sources
325 * such as those generated in thread_userret() itself.
326 */
327 void
328 cpu_set_upcall(struct thread *td, void *pcb)
329 {
330 struct pcb *pcb2;
331
332 td->td_flags |= TDF_UPCALLING;
333
334 /* Point the pcb to the top of the stack. */
335 pcb2 = td->td_pcb;
336
337 /*
338 * Copy the upcall pcb. This loads kernel regs.
339 * Those not loaded individually below get their default
340 * values here.
341 *
342 * XXXKSE It might be a good idea to simply skip this as
343 * the values of the other registers may be unimportant.
344 * This would remove any requirement for knowing the KSE
345 * at this time (see the matching comment below for
346 * more analysis) (need a good safe default).
347 */
348 bcopy(pcb, pcb2, sizeof(*pcb2));
349
350 /*
351 * Create a new fresh stack for the new thread.
352 * The -16 is so we can expand the trapframe if we go to vm86.
353 * Don't forget to set this stack value into whatever supplies
354 * the address for the fault handlers.
355 * The contexts are filled in at the time we actually DO the
356 * upcall as only then do we know which KSE we got.
357 */
358 td->td_frame = (struct trapframe *)((caddr_t)pcb2 - 16) - 1;
359
360 /*
361 * Set registers for trampoline to user mode. Leave space for the
362 * return address on stack. These are the kernel mode register values.
363 */
364 pcb2->pcb_cr3 = vtophys(vmspace_pmap(td->td_proc->p_vmspace)->pm_pdir);
365 pcb2->pcb_edi = 0;
366 pcb2->pcb_esi = (int)fork_return; /* trampoline arg */
367 pcb2->pcb_ebp = 0;
368 pcb2->pcb_esp = (int)td->td_frame - sizeof(void *); /* trampoline arg */
369 pcb2->pcb_ebx = (int)td; /* trampoline arg */
370 pcb2->pcb_eip = (int)fork_trampoline;
371 pcb2->pcb_psl &= ~(PSL_I); /* interrupts must be disabled */
372 /*
373 * If we didn't copy the pcb, we'd need to do the following registers:
374 * pcb2->pcb_dr*: cloned above.
375 * pcb2->pcb_savefpu: cloned above.
376 * pcb2->pcb_flags: cloned above.
377 * pcb2->pcb_onfault: cloned above (always NULL here?).
378 * pcb2->pcb_gs: cloned above. XXXKSE ???
379 * pcb2->pcb_ext: cleared below.
380 */
381 pcb2->pcb_ext = NULL;
382 }
383
384 /*
385 * Set that machine state for performing an upcall that has to
386 * be done in thread_userret() so that those upcalls generated
387 * in thread_userret() itself can be done as well.
388 */
389 void
390 cpu_set_upcall_kse(struct thread *td, struct kse *ke)
391 {
392
393 /*
394 * Do any extra cleaning that needs to be done.
395 * The thread may have optional components
396 * that are not present in a fresh thread.
397 * This may be a recycled thread so make it look
398 * as though it's newly allocated.
399 */
400 cpu_thread_clean(td);
401
402 /*
403 * Set the trap frame to point at the beginning of the uts
404 * function.
405 */
406 td->td_frame->tf_esp =
407 (int)ke->ke_stack.ss_sp + ke->ke_stack.ss_size - 16;
408 td->td_frame->tf_eip = (int)ke->ke_upcall;
409
410 /*
411 * Pass the address of the mailbox for this kse to the uts
412 * function as a parameter on the stack.
413 */
414 suword((void *)(td->td_frame->tf_esp + sizeof(void *)),
415 (int)ke->ke_mailbox);
416 }
417
418 void
419 cpu_wait(p)
420 struct proc *p;
421 {
422 }
423
424 /*
425 * Convert kernel VA to physical address
426 */
427 u_long
428 kvtop(void *addr)
429 {
430 vm_offset_t va;
431
432 va = pmap_kextract((vm_offset_t)addr);
433 if (va == 0)
434 panic("kvtop: zero page frame");
435 return((int)va);
436 }
437
438 /*
439 * Map an IO request into kernel virtual address space.
440 *
441 * All requests are (re)mapped into kernel VA space.
442 * Notice that we use b_bufsize for the size of the buffer
443 * to be mapped. b_bcount might be modified by the driver.
444 */
445 void
446 vmapbuf(bp)
447 register struct buf *bp;
448 {
449 register caddr_t addr, kva;
450 vm_offset_t pa;
451 int pidx;
452 struct vm_page *m;
453
454 GIANT_REQUIRED;
455
456 if ((bp->b_flags & B_PHYS) == 0)
457 panic("vmapbuf");
458
459 for (addr = (caddr_t)trunc_page((vm_offset_t)bp->b_data), pidx = 0;
460 addr < bp->b_data + bp->b_bufsize;
461 addr += PAGE_SIZE, pidx++) {
462 /*
463 * Do the vm_fault if needed; do the copy-on-write thing
464 * when reading stuff off device into memory.
465 */
466 vm_fault_quick((addr >= bp->b_data) ? addr : bp->b_data,
467 (bp->b_iocmd == BIO_READ)?(VM_PROT_READ|VM_PROT_WRITE):VM_PROT_READ);
468 pa = trunc_page(pmap_kextract((vm_offset_t) addr));
469 if (pa == 0)
470 panic("vmapbuf: page not present");
471 m = PHYS_TO_VM_PAGE(pa);
472 vm_page_hold(m);
473 bp->b_pages[pidx] = m;
474 }
475 if (pidx > btoc(MAXPHYS))
476 panic("vmapbuf: mapped more than MAXPHYS");
477 pmap_qenter((vm_offset_t)bp->b_saveaddr, bp->b_pages, pidx);
478
479 kva = bp->b_saveaddr;
480 bp->b_npages = pidx;
481 bp->b_saveaddr = bp->b_data;
482 bp->b_data = kva + (((vm_offset_t) bp->b_data) & PAGE_MASK);
483 }
484
485 /*
486 * Free the io map PTEs associated with this IO operation.
487 * We also invalidate the TLB entries and restore the original b_addr.
488 */
489 void
490 vunmapbuf(bp)
491 register struct buf *bp;
492 {
493 int pidx;
494 int npages;
495
496 GIANT_REQUIRED;
497
498 if ((bp->b_flags & B_PHYS) == 0)
499 panic("vunmapbuf");
500
501 npages = bp->b_npages;
502 pmap_qremove(trunc_page((vm_offset_t)bp->b_data),
503 npages);
504 vm_page_lock_queues();
505 for (pidx = 0; pidx < npages; pidx++)
506 vm_page_unhold(bp->b_pages[pidx]);
507 vm_page_unlock_queues();
508
509 bp->b_data = bp->b_saveaddr;
510 }
511
512 /*
513 * Force reset the processor by invalidating the entire address space!
514 */
515
516 #ifdef SMP
517 static void
518 cpu_reset_proxy()
519 {
520
521 cpu_reset_proxy_active = 1;
522 while (cpu_reset_proxy_active == 1)
523 ; /* Wait for other cpu to see that we've started */
524 stop_cpus((1<<cpu_reset_proxyid));
525 printf("cpu_reset_proxy: Stopped CPU %d\n", cpu_reset_proxyid);
526 DELAY(1000000);
527 cpu_reset_real();
528 }
529 #endif
530
531 void
532 cpu_reset()
533 {
534 #ifdef SMP
535 if (smp_active == 0) {
536 cpu_reset_real();
537 /* NOTREACHED */
538 } else {
539
540 u_int map;
541 int cnt;
542 printf("cpu_reset called on cpu#%d\n", PCPU_GET(cpuid));
543
544 map = PCPU_GET(other_cpus) & ~ stopped_cpus;
545
546 if (map != 0) {
547 printf("cpu_reset: Stopping other CPUs\n");
548 stop_cpus(map); /* Stop all other CPUs */
549 }
550
551 if (PCPU_GET(cpuid) == 0) {
552 DELAY(1000000);
553 cpu_reset_real();
554 /* NOTREACHED */
555 } else {
556 /* We are not BSP (CPU #0) */
557
558 cpu_reset_proxyid = PCPU_GET(cpuid);
559 cpustop_restartfunc = cpu_reset_proxy;
560 cpu_reset_proxy_active = 0;
561 printf("cpu_reset: Restarting BSP\n");
562 started_cpus = (1<<0); /* Restart CPU #0 */
563
564 cnt = 0;
565 while (cpu_reset_proxy_active == 0 && cnt < 10000000)
566 cnt++; /* Wait for BSP to announce restart */
567 if (cpu_reset_proxy_active == 0)
568 printf("cpu_reset: Failed to restart BSP\n");
569 enable_intr();
570 cpu_reset_proxy_active = 2;
571
572 while (1);
573 /* NOTREACHED */
574 }
575 }
576 #else
577 cpu_reset_real();
578 #endif
579 }
580
581 static void
582 cpu_reset_real()
583 {
584
585 #ifdef PC98
586 /*
587 * Attempt to do a CPU reset via CPU reset port.
588 */
589 disable_intr();
590 if ((inb(0x35) & 0xa0) != 0xa0) {
591 outb(0x37, 0x0f); /* SHUT0 = 0. */
592 outb(0x37, 0x0b); /* SHUT1 = 0. */
593 }
594 outb(0xf0, 0x00); /* Reset. */
595 #else
596 /*
597 * Attempt to do a CPU reset via the keyboard controller,
598 * do not turn of the GateA20, as any machine that fails
599 * to do the reset here would then end up in no man's land.
600 */
601
602 #if !defined(BROKEN_KEYBOARD_RESET)
603 outb(IO_KBD + 4, 0xFE);
604 DELAY(500000); /* wait 0.5 sec to see if that did it */
605 printf("Keyboard reset did not work, attempting CPU shutdown\n");
606 DELAY(1000000); /* wait 1 sec for printf to complete */
607 #endif
608 #endif /* PC98 */
609 /* force a shutdown by unmapping entire address space ! */
610 bzero((caddr_t) PTD, PAGE_SIZE);
611
612 /* "good night, sweet prince .... <THUNK!>" */
613 invltlb();
614 /* NOTREACHED */
615 while(1);
616 }
617
618 /*
619 * Software interrupt handler for queued VM system processing.
620 */
621 void
622 swi_vm(void *dummy)
623 {
624 if (busdma_swi_pending != 0)
625 busdma_swi();
626 }
627
628 /*
629 * Tell whether this address is in some physical memory region.
630 * Currently used by the kernel coredump code in order to avoid
631 * dumping the ``ISA memory hole'' which could cause indefinite hangs,
632 * or other unpredictable behaviour.
633 */
634
635 int
636 is_physical_memory(addr)
637 vm_offset_t addr;
638 {
639
640 #ifdef DEV_ISA
641 /* The ISA ``memory hole''. */
642 if (addr >= 0xa0000 && addr < 0x100000)
643 return 0;
644 #endif
645
646 /*
647 * stuff other tests for known memory-mapped devices (PCI?)
648 * here
649 */
650
651 return 1;
652 }
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