vm_machdep.c revision 113364
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: head/sys/amd64/amd64/vm_machdep.c 113364 2003-04-11 14:47:34Z davidxu $
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
90static void	cpu_reset_real(void);
91#ifdef SMP
92static void	cpu_reset_proxy(void);
93static u_int	cpu_reset_proxyid;
94static volatile u_int	cpu_reset_proxy_active;
95#endif
96extern int	_ucodesel, _udatasel;
97
98/*
99 * Finish a fork operation, with process p2 nearly set up.
100 * Copy and update the pcb, set up the stack so that the child
101 * ready to run and return to user mode.
102 */
103void
104cpu_fork(td1, p2, td2, flags)
105	register struct thread *td1;
106	register struct proc *p2;
107	struct thread *td2;
108	int flags;
109{
110	register struct proc *p1;
111	struct pcb *pcb2;
112	struct mdproc *mdp2;
113#ifdef DEV_NPX
114	register_t savecrit;
115#endif
116
117	p1 = td1->td_proc;
118	if ((flags & RFPROC) == 0) {
119		if ((flags & RFMEM) == 0) {
120			/* unshare user LDT */
121			struct mdproc *mdp1 = &p1->p_md;
122			struct proc_ldt *pldt = mdp1->md_ldt;
123			if (pldt && pldt->ldt_refcnt > 1) {
124				pldt = user_ldt_alloc(mdp1, pldt->ldt_len);
125				if (pldt == NULL)
126					panic("could not copy LDT");
127				mdp1->md_ldt = pldt;
128				set_user_ldt(mdp1);
129				user_ldt_free(td1);
130			}
131		}
132		return;
133	}
134
135	/* Ensure that p1's pcb is up to date. */
136#ifdef DEV_NPX
137	if (td1 == curthread)
138		td1->td_pcb->pcb_gs = rgs();
139	savecrit = intr_disable();
140	if (PCPU_GET(fpcurthread) == td1)
141		npxsave(&td1->td_pcb->pcb_save);
142	intr_restore(savecrit);
143#endif
144
145	/* Point the pcb to the top of the stack */
146	pcb2 = (struct pcb *)(td2->td_kstack + KSTACK_PAGES * PAGE_SIZE) - 1;
147	td2->td_pcb = pcb2;
148
149	/* Copy p1's pcb */
150	bcopy(td1->td_pcb, pcb2, sizeof(*pcb2));
151
152	/* Point mdproc and then copy over td1's contents */
153	mdp2 = &p2->p_md;
154	bcopy(&p1->p_md, mdp2, sizeof(*mdp2));
155
156	/*
157	 * Create a new fresh stack for the new process.
158	 * Copy the trap frame for the return to user mode as if from a
159	 * syscall.  This copies most of the user mode register values.
160	 * The -16 is so we can expand the trapframe if we go to vm86.
161	 */
162	td2->td_frame = (struct trapframe *)((caddr_t)td2->td_pcb - 16) - 1;
163	bcopy(td1->td_frame, td2->td_frame, sizeof(struct trapframe));
164
165	td2->td_frame->tf_eax = 0;		/* Child returns zero */
166	td2->td_frame->tf_eflags &= ~PSL_C;	/* success */
167	td2->td_frame->tf_edx = 1;
168
169	/*
170	 * Set registers for trampoline to user mode.  Leave space for the
171	 * return address on stack.  These are the kernel mode register values.
172	 */
173#ifdef PAE
174	pcb2->pcb_cr3 = vtophys(vmspace_pmap(p2->p_vmspace)->pm_pdpt);
175#else
176	pcb2->pcb_cr3 = vtophys(vmspace_pmap(p2->p_vmspace)->pm_pdir);
177#endif
178	pcb2->pcb_edi = 0;
179	pcb2->pcb_esi = (int)fork_return;	/* fork_trampoline argument */
180	pcb2->pcb_ebp = 0;
181	pcb2->pcb_esp = (int)td2->td_frame - sizeof(void *);
182	pcb2->pcb_ebx = (int)td2;		/* fork_trampoline argument */
183	pcb2->pcb_eip = (int)fork_trampoline;
184	pcb2->pcb_psl = td2->td_frame->tf_eflags & ~PSL_I; /* ints disabled */
185	pcb2->pcb_gs = rgs();
186	/*-
187	 * pcb2->pcb_dr*:	cloned above.
188	 * pcb2->pcb_savefpu:	cloned above.
189	 * pcb2->pcb_flags:	cloned above.
190	 * pcb2->pcb_onfault:	cloned above (always NULL here?).
191	 * pcb2->pcb_gs:	cloned above.
192	 * pcb2->pcb_ext:	cleared below.
193	 */
194
195	/*
196	 * XXX don't copy the i/o pages.  this should probably be fixed.
197	 */
198	pcb2->pcb_ext = 0;
199
200        /* Copy the LDT, if necessary. */
201	mtx_lock_spin(&sched_lock);
202        if (mdp2->md_ldt != 0) {
203		if (flags & RFMEM) {
204			mdp2->md_ldt->ldt_refcnt++;
205		} else {
206			mdp2->md_ldt = user_ldt_alloc(mdp2,
207			    mdp2->md_ldt->ldt_len);
208			if (mdp2->md_ldt == NULL)
209				panic("could not copy LDT");
210		}
211        }
212	mtx_unlock_spin(&sched_lock);
213
214	/*
215	 * Now, cpu_switch() can schedule the new process.
216	 * pcb_esp is loaded pointing to the cpu_switch() stack frame
217	 * containing the return address when exiting cpu_switch.
218	 * This will normally be to fork_trampoline(), which will have
219	 * %ebx loaded with the new proc's pointer.  fork_trampoline()
220	 * will set up a stack to call fork_return(p, frame); to complete
221	 * the return to user-mode.
222	 */
223}
224
225/*
226 * Intercept the return address from a freshly forked process that has NOT
227 * been scheduled yet.
228 *
229 * This is needed to make kernel threads stay in kernel mode.
230 */
231void
232cpu_set_fork_handler(td, func, arg)
233	struct thread *td;
234	void (*func)(void *);
235	void *arg;
236{
237	/*
238	 * Note that the trap frame follows the args, so the function
239	 * is really called like this:  func(arg, frame);
240	 */
241	td->td_pcb->pcb_esi = (int) func;	/* function */
242	td->td_pcb->pcb_ebx = (int) arg;	/* first arg */
243}
244
245void
246cpu_exit(struct thread *td)
247{
248	struct mdproc *mdp;
249
250	mdp = &td->td_proc->p_md;
251	if (mdp->md_ldt)
252		user_ldt_free(td);
253	reset_dbregs();
254}
255
256void
257cpu_thread_exit(struct thread *td)
258{
259	struct pcb *pcb = td->td_pcb;
260#ifdef DEV_NPX
261	npxexit(td);
262#endif
263        if (pcb->pcb_flags & PCB_DBREGS) {
264                /*
265                 * disable all hardware breakpoints
266                 */
267                reset_dbregs();
268                pcb->pcb_flags &= ~PCB_DBREGS;
269        }
270}
271
272void
273cpu_thread_clean(struct thread *td)
274{
275	struct pcb *pcb;
276
277	pcb = td->td_pcb;
278	if (pcb->pcb_ext != 0) {
279		/* XXXKSE  XXXSMP  not SMP SAFE.. what locks do we have? */
280		/* if (pcb->pcb_ext->ext_refcount-- == 1) ?? */
281		/*
282		 * XXX do we need to move the TSS off the allocated pages
283		 * before freeing them?  (not done here)
284		 */
285		mtx_lock(&Giant);
286		kmem_free(kernel_map, (vm_offset_t)pcb->pcb_ext,
287		    ctob(IOPAGES + 1));
288		mtx_unlock(&Giant);
289		pcb->pcb_ext = 0;
290	}
291}
292
293void
294cpu_sched_exit(td)
295	register struct thread *td;
296{
297}
298
299void
300cpu_thread_setup(struct thread *td)
301{
302
303	td->td_pcb =
304	     (struct pcb *)(td->td_kstack + KSTACK_PAGES * PAGE_SIZE) - 1;
305	td->td_frame = (struct trapframe *)((caddr_t)td->td_pcb - 16) - 1;
306}
307
308/*
309 * Initialize machine state (pcb and trap frame) for a new thread about to
310 * upcall. Pu t enough state in the new thread's PCB to get it to go back
311 * userret(), where we can intercept it again to set the return (upcall)
312 * Address and stack, along with those from upcals that are from other sources
313 * such as those generated in thread_userret() itself.
314 */
315void
316cpu_set_upcall(struct thread *td, void *pcb)
317{
318	struct pcb *pcb2;
319
320	/* Point the pcb to the top of the stack. */
321	pcb2 = td->td_pcb;
322
323	/*
324	 * Copy the upcall pcb.  This loads kernel regs.
325	 * Those not loaded individually below get their default
326	 * values here.
327	 *
328	 * XXXKSE It might be a good idea to simply skip this as
329	 * the values of the other registers may be unimportant.
330	 * This would remove any requirement for knowing the KSE
331	 * at this time (see the matching comment below for
332	 * more analysis) (need a good safe default).
333	 */
334	bcopy(pcb, pcb2, sizeof(*pcb2));
335
336	/*
337	 * Create a new fresh stack for the new thread.
338	 * The -16 is so we can expand the trapframe if we go to vm86.
339	 * Don't forget to set this stack value into whatever supplies
340	 * the address for the fault handlers.
341	 * The contexts are filled in at the time we actually DO the
342	 * upcall as only then do we know which KSE we got.
343	 */
344	td->td_frame = (struct trapframe *)((caddr_t)pcb2 - 16) - 1;
345
346	/*
347	 * Set registers for trampoline to user mode.  Leave space for the
348	 * return address on stack.  These are the kernel mode register values.
349	 */
350#ifdef PAE
351	pcb2->pcb_cr3 = vtophys(vmspace_pmap(td->td_proc->p_vmspace)->pm_pdpt);
352#else
353	pcb2->pcb_cr3 = vtophys(vmspace_pmap(td->td_proc->p_vmspace)->pm_pdir);
354#endif
355	pcb2->pcb_edi = 0;
356	pcb2->pcb_esi = (int)fork_return;		    /* trampoline arg */
357	pcb2->pcb_ebp = 0;
358	pcb2->pcb_esp = (int)td->td_frame - sizeof(void *); /* trampoline arg */
359	pcb2->pcb_ebx = (int)td;			    /* trampoline arg */
360	pcb2->pcb_eip = (int)fork_trampoline;
361	pcb2->pcb_psl &= ~(PSL_I);	/* interrupts must be disabled */
362	pcb2->pcb_gs = rgs();
363	/*
364	 * If we didn't copy the pcb, we'd need to do the following registers:
365	 * pcb2->pcb_dr*:	cloned above.
366	 * pcb2->pcb_savefpu:	cloned above.
367	 * pcb2->pcb_flags:	cloned above.
368	 * pcb2->pcb_onfault:	cloned above (always NULL here?).
369	 * pcb2->pcb_gs:	cloned above.  XXXKSE ???
370	 * pcb2->pcb_ext:	cleared below.
371	 */
372	 pcb2->pcb_ext = NULL;
373}
374
375/*
376 * Set that machine state for performing an upcall that has to
377 * be done in thread_userret() so that those upcalls generated
378 * in thread_userret() itself can be done as well.
379 */
380void
381cpu_set_upcall_kse(struct thread *td, struct kse_upcall *ku)
382{
383
384	/*
385	 * Do any extra cleaning that needs to be done.
386	 * The thread may have optional components
387	 * that are not present in a fresh thread.
388	 * This may be a recycled thread so make it look
389	 * as though it's newly allocated.
390	 */
391	cpu_thread_clean(td);
392
393	/*
394	 * Set the trap frame to point at the beginning of the uts
395	 * function.
396	 */
397	td->td_frame->tf_esp =
398	    (int)ku->ku_stack.ss_sp + ku->ku_stack.ss_size - 16;
399	td->td_frame->tf_eip = (int)ku->ku_func;
400
401	/*
402	 * Pass the address of the mailbox for this kse to the uts
403	 * function as a parameter on the stack.
404	 */
405	suword((void *)(td->td_frame->tf_esp + sizeof(void *)),
406	    (int)ku->ku_mailbox);
407}
408
409void
410cpu_wait(p)
411	struct proc *p;
412{
413}
414
415/*
416 * Convert kernel VA to physical address
417 */
418vm_paddr_t
419kvtop(void *addr)
420{
421	vm_paddr_t pa;
422
423	pa = pmap_kextract((vm_offset_t)addr);
424	if (pa == 0)
425		panic("kvtop: zero page frame");
426	return (pa);
427}
428
429/*
430 * Force reset the processor by invalidating the entire address space!
431 */
432
433#ifdef SMP
434static void
435cpu_reset_proxy()
436{
437
438	cpu_reset_proxy_active = 1;
439	while (cpu_reset_proxy_active == 1)
440		;	 /* Wait for other cpu to see that we've started */
441	stop_cpus((1<<cpu_reset_proxyid));
442	printf("cpu_reset_proxy: Stopped CPU %d\n", cpu_reset_proxyid);
443	DELAY(1000000);
444	cpu_reset_real();
445}
446#endif
447
448void
449cpu_reset()
450{
451#ifdef SMP
452	if (smp_active == 0) {
453		cpu_reset_real();
454		/* NOTREACHED */
455	} else {
456
457		u_int map;
458		int cnt;
459		printf("cpu_reset called on cpu#%d\n", PCPU_GET(cpuid));
460
461		map = PCPU_GET(other_cpus) & ~ stopped_cpus;
462
463		if (map != 0) {
464			printf("cpu_reset: Stopping other CPUs\n");
465			stop_cpus(map);		/* Stop all other CPUs */
466		}
467
468		if (PCPU_GET(cpuid) == 0) {
469			DELAY(1000000);
470			cpu_reset_real();
471			/* NOTREACHED */
472		} else {
473			/* We are not BSP (CPU #0) */
474
475			cpu_reset_proxyid = PCPU_GET(cpuid);
476			cpustop_restartfunc = cpu_reset_proxy;
477			cpu_reset_proxy_active = 0;
478			printf("cpu_reset: Restarting BSP\n");
479			started_cpus = (1<<0);		/* Restart CPU #0 */
480
481			cnt = 0;
482			while (cpu_reset_proxy_active == 0 && cnt < 10000000)
483				cnt++;	/* Wait for BSP to announce restart */
484			if (cpu_reset_proxy_active == 0)
485				printf("cpu_reset: Failed to restart BSP\n");
486			enable_intr();
487			cpu_reset_proxy_active = 2;
488
489			while (1);
490			/* NOTREACHED */
491		}
492	}
493#else
494	cpu_reset_real();
495#endif
496}
497
498static void
499cpu_reset_real()
500{
501
502#ifdef PC98
503	/*
504	 * Attempt to do a CPU reset via CPU reset port.
505	 */
506	disable_intr();
507	if ((inb(0x35) & 0xa0) != 0xa0) {
508		outb(0x37, 0x0f);		/* SHUT0 = 0. */
509		outb(0x37, 0x0b);		/* SHUT1 = 0. */
510	}
511	outb(0xf0, 0x00);		/* Reset. */
512#else
513	/*
514	 * Attempt to do a CPU reset via the keyboard controller,
515	 * do not turn of the GateA20, as any machine that fails
516	 * to do the reset here would then end up in no man's land.
517	 */
518
519#if !defined(BROKEN_KEYBOARD_RESET)
520	outb(IO_KBD + 4, 0xFE);
521	DELAY(500000);	/* wait 0.5 sec to see if that did it */
522	printf("Keyboard reset did not work, attempting CPU shutdown\n");
523	DELAY(1000000);	/* wait 1 sec for printf to complete */
524#endif
525#endif /* PC98 */
526	/* force a shutdown by unmapping entire address space ! */
527	bzero((caddr_t)PTD, NBPTD);
528
529	/* "good night, sweet prince .... <THUNK!>" */
530	invltlb();
531	/* NOTREACHED */
532	while(1);
533}
534
535/*
536 * Software interrupt handler for queued VM system processing.
537 */
538void
539swi_vm(void *dummy)
540{
541	if (busdma_swi_pending != 0)
542		busdma_swi();
543}
544
545/*
546 * Tell whether this address is in some physical memory region.
547 * Currently used by the kernel coredump code in order to avoid
548 * dumping the ``ISA memory hole'' which could cause indefinite hangs,
549 * or other unpredictable behaviour.
550 */
551
552int
553is_physical_memory(addr)
554	vm_offset_t addr;
555{
556
557#ifdef DEV_ISA
558	/* The ISA ``memory hole''. */
559	if (addr >= 0xa0000 && addr < 0x100000)
560		return 0;
561#endif
562
563	/*
564	 * stuff other tests for known memory-mapped devices (PCI?)
565	 * here
566	 */
567
568	return 1;
569}
570