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 * Copyright (c) 2008 The DragonFly Project.
8 * This code is derived from software contributed to Berkeley by
9 * the Systems Programming Group of the University of Utah Computer
10 * Science Department, and William Jolitz.
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. All advertising materials mentioning features or use of this software
21 * must display the following acknowledgement:
22 * This product includes software developed by the University of
23 * California, Berkeley and its contributors.
24 * 4. Neither the name of the University nor the names of its contributors
25 * may be used to endorse or promote products derived from this software
26 * without specific prior written permission.
28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
40 * from: @(#)vm_machdep.c 7.3 (Berkeley) 5/13/91
41 * Utah $Hdr: vm_machdep.c 1.16.1.1 89/06/23$
42 * $FreeBSD: src/sys/i386/i386/vm_machdep.c,v 1.132.2.9 2003/01/25 19:02:23 dillon Exp $
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/malloc.h>
50 #include <sys/interrupt.h>
51 #include <sys/vnode.h>
52 #include <sys/vmmeter.h>
53 #include <sys/kernel.h>
54 #include <sys/sysctl.h>
55 #include <sys/unistd.h>
57 #include <machine/clock.h>
58 #include <machine/cpu.h>
59 #include <machine/md_var.h>
60 #include <machine/smp.h>
61 #include <machine/pcb.h>
62 #include <machine/pcb_ext.h>
63 #include <machine/segments.h>
64 #include <machine/globaldata.h> /* npxthread */
65 #include <machine/vmm.h>
68 #include <vm/vm_param.h>
70 #include <vm/vm_kern.h>
71 #include <vm/vm_page.h>
72 #include <vm/vm_map.h>
73 #include <vm/vm_extern.h>
75 #include <sys/thread2.h>
76 #include <sys/mplock2.h>
78 #include <bus/isa/isa.h>
80 static void cpu_reset_real (void);
82 * Finish a fork operation, with lwp lp2 nearly set up.
83 * Copy and update the pcb, set up the stack so that the child
84 * ready to run and return to user mode.
87 cpu_fork(struct lwp *lp1, struct lwp *lp2, int flags)
91 if ((flags & RFPROC) == 0) {
92 if ((flags & RFMEM) == 0) {
93 /* unshare user LDT */
94 struct pcb *pcb1 = lp1->lwp_thread->td_pcb;
95 struct pcb_ldt *pcb_ldt = pcb1->pcb_ldt;
96 if (pcb_ldt && pcb_ldt->ldt_refcnt > 1) {
97 pcb_ldt = user_ldt_alloc(pcb1,pcb_ldt->ldt_len);
99 pcb1->pcb_ldt = pcb_ldt;
106 /* Ensure that lp1's pcb is up to date. */
107 if (mdcpu->gd_npxthread == lp1->lwp_thread)
108 npxsave(lp1->lwp_thread->td_savefpu);
111 * Copy lp1's PCB. This really only applies to the
112 * debug registers and FP state, but its faster to just copy the
113 * whole thing. Because we only save the PCB at switchout time,
114 * the register state may not be current.
116 pcb2 = lp2->lwp_thread->td_pcb;
117 *pcb2 = *lp1->lwp_thread->td_pcb;
120 * Create a new fresh stack for the new process.
121 * Copy the trap frame for the return to user mode as if from a
122 * syscall. This copies the user mode register values.
124 * pcb_rsp must allocate an additional call-return pointer below
125 * the trap frame which will be restored by cpu_heavy_restore from
126 * PCB_RIP, and the thread's td_sp pointer must allocate an
127 * additonal two quadwords below the pcb_rsp call-return pointer to
128 * hold the LWKT restore function pointer and rflags.
130 * The LWKT restore function pointer must be set to cpu_heavy_restore,
131 * which is our standard heavy-weight process switch-in function.
132 * YYY eventually we should shortcut fork_return and fork_trampoline
133 * to use the LWKT restore function directly so we can get rid of
134 * all the extra crap we are setting up.
136 lp2->lwp_md.md_regs = (struct trapframe *)pcb2 - 1;
137 bcopy(lp1->lwp_md.md_regs, lp2->lwp_md.md_regs, sizeof(*lp2->lwp_md.md_regs));
140 * Set registers for trampoline to user mode. Leave space for the
141 * return address on stack. These are the kernel mode register values.
143 pcb2->pcb_cr3 = vtophys(vmspace_pmap(lp2->lwp_proc->p_vmspace)->pm_pml4);
144 pcb2->pcb_rbx = (unsigned long)fork_return; /* fork_trampoline argument */
146 pcb2->pcb_rsp = (unsigned long)lp2->lwp_md.md_regs - sizeof(void *);
147 pcb2->pcb_r12 = (unsigned long)lp2; /* fork_trampoline argument */
151 pcb2->pcb_rip = (unsigned long)fork_trampoline;
152 lp2->lwp_thread->td_sp = (char *)(pcb2->pcb_rsp - sizeof(void *));
153 *(u_int64_t *)lp2->lwp_thread->td_sp = PSL_USER;
154 lp2->lwp_thread->td_sp -= sizeof(void *);
155 *(void **)lp2->lwp_thread->td_sp = (void *)cpu_heavy_restore;
158 * pcb2->pcb_ldt: duplicated below, if necessary.
159 * pcb2->pcb_savefpu: cloned above.
160 * pcb2->pcb_flags: cloned above (always 0 here?).
161 * pcb2->pcb_onfault: cloned above (always NULL here).
162 * pcb2->pcb_onfault_sp:cloned above (dont care)
166 * XXX don't copy the i/o pages. this should probably be fixed.
168 pcb2->pcb_ext = NULL;
170 /* Copy the LDT, if necessary. */
171 if (pcb2->pcb_ldt != NULL) {
173 pcb2->pcb_ldt->ldt_refcnt++;
175 pcb2->pcb_ldt = user_ldt_alloc(pcb2,
176 pcb2->pcb_ldt->ldt_len);
179 bcopy(&lp1->lwp_thread->td_tls, &lp2->lwp_thread->td_tls,
180 sizeof(lp2->lwp_thread->td_tls));
182 * Now, cpu_switch() can schedule the new lwp.
183 * pcb_rsp is loaded pointing to the cpu_switch() stack frame
184 * containing the return address when exiting cpu_switch.
185 * This will normally be to fork_trampoline(), which will have
186 * %rbx loaded with the new lwp's pointer. fork_trampoline()
187 * will set up a stack to call fork_return(lp, frame); to complete
188 * the return to user-mode.
193 * Prepare new lwp to return to the address specified in params.
196 cpu_prepare_lwp(struct lwp *lp, struct lwp_params *params)
198 struct trapframe *regs = lp->lwp_md.md_regs;
199 void *bad_return = NULL;
202 regs->tf_rip = (long)params->lwp_func;
203 regs->tf_rsp = (long)params->lwp_stack;
204 /* Set up argument for function call */
205 regs->tf_rdi = (long)params->lwp_arg;
208 * Set up fake return address. As the lwp function may never return,
209 * we simply copy out a NULL pointer and force the lwp to receive
210 * a SIGSEGV if it returns anyways.
212 regs->tf_rsp -= sizeof(void *);
213 error = copyout(&bad_return, (void *)regs->tf_rsp, sizeof(bad_return));
217 if (lp->lwp_proc->p_vmm) {
218 lp->lwp_thread->td_pcb->pcb_cr3 = KPML4phys;
219 cpu_set_fork_handler(lp,
220 (void (*)(void *, struct trapframe *))vmm_lwp_return, lp);
222 cpu_set_fork_handler(lp,
223 (void (*)(void *, struct trapframe *))generic_lwp_return, lp);
229 * Intercept the return address from a freshly forked process that has NOT
230 * been scheduled yet.
232 * This is needed to make kernel threads stay in kernel mode.
235 cpu_set_fork_handler(struct lwp *lp, void (*func)(void *, struct trapframe *),
239 * Note that the trap frame follows the args, so the function
240 * is really called like this: func(arg, frame);
242 lp->lwp_thread->td_pcb->pcb_rbx = (long)func; /* function */
243 lp->lwp_thread->td_pcb->pcb_r12 = (long)arg; /* first arg */
247 cpu_set_thread_handler(thread_t td, void (*rfunc)(void), void *func, void *arg)
249 td->td_pcb->pcb_rbx = (long)func;
250 td->td_pcb->pcb_r12 = (long)arg;
251 td->td_switch = cpu_lwkt_switch;
252 td->td_sp -= sizeof(void *);
253 *(void **)td->td_sp = rfunc; /* exit function on return */
254 td->td_sp -= sizeof(void *);
255 *(void **)td->td_sp = cpu_kthread_restore;
261 struct thread *td = curthread;
266 /* Some i386 functionality was dropped */
267 KKASSERT(pcb->pcb_ext == NULL);
270 * disable all hardware breakpoints
272 if (pcb->pcb_flags & PCB_DBREGS) {
274 pcb->pcb_flags &= ~PCB_DBREGS;
276 td->td_gd->gd_cnt.v_swtch++;
278 crit_enter_quick(td);
279 if (td->td_flags & TDF_TSLEEPQ)
281 lwkt_deschedule_self(td);
282 lwkt_remove_tdallq(td);
287 * Terminate the current thread. The caller must have already acquired
288 * the thread's rwlock and placed it on a reap list or otherwise notified
289 * a reaper of its existance. We set a special assembly switch function which
290 * releases td_rwlock after it has cleaned up the MMU state and switched
293 * Must be caller from a critical section and with the thread descheduled.
296 cpu_thread_exit(void)
299 curthread->td_switch = cpu_exit_switch;
300 curthread->td_flags |= TDF_EXITING;
302 panic("cpu_thread_exit: lwkt_switch() unexpectedly returned");
315 * Attempt to do a CPU reset via the keyboard controller,
316 * do not turn of the GateA20, as any machine that fails
317 * to do the reset here would then end up in no man's land.
320 #if !defined(BROKEN_KEYBOARD_RESET)
321 outb(IO_KBD + 4, 0xFE);
322 DELAY(500000); /* wait 0.5 sec to see if that did it */
323 kprintf("Keyboard reset did not work, attempting CPU shutdown\n");
324 DELAY(1000000); /* wait 1 sec for kprintf to complete */
327 /* force a shutdown by unmapping entire address space ! */
328 bzero((caddr_t) PTD, PAGE_SIZE);
331 /* "good night, sweet prince .... <THUNK!>" */
338 * Convert kernel VA to physical address
345 pa = pmap_kextract((vm_offset_t)addr);
347 panic("kvtop: zero page frame");
352 swi_vm(void *arg, void *frame)
354 if (busdma_swi_pending != 0)
359 swi_vm_setup(void *arg)
361 register_swi(SWI_VM, swi_vm, NULL, "swi_vm", NULL, 0);
364 SYSINIT(vm_setup, SI_BOOT2_MACHDEP, SI_ORDER_ANY, swi_vm_setup, NULL);
367 * platform-specific vmspace initialization (nothing for x86_64)
370 cpu_vmspace_alloc(struct vmspace *vm __unused)
375 cpu_vmspace_free(struct vmspace *vm __unused)
380 kvm_access_check(vm_offset_t saddr, vm_offset_t eaddr, int prot)
384 if (saddr < KvaStart)
388 for (addr = saddr; addr < eaddr; addr += PAGE_SIZE) {
389 if (pmap_extract(&kernel_pmap, addr) == 0)
392 if (!kernacc((caddr_t)saddr, eaddr - saddr, prot))
399 void _test_frame_enter(struct trapframe *frame);
400 void _test_frame_exit(struct trapframe *frame);
403 _test_frame_enter(struct trapframe *frame)
405 thread_t td = curthread;
407 if (ISPL(frame->tf_cs) == SEL_UPL) {
408 KKASSERT(td->td_lwp);
409 KASSERT(td->td_lwp->lwp_md.md_regs == frame,
410 ("_test_frame_exit: Frame mismatch %p %p",
411 td->td_lwp->lwp_md.md_regs, frame));
412 td->td_lwp->lwp_saveusp = (void *)frame->tf_rsp;
413 td->td_lwp->lwp_saveupc = (void *)frame->tf_rip;
415 if ((char *)frame < td->td_kstack ||
416 (char *)frame > td->td_kstack + td->td_kstack_size) {
417 panic("_test_frame_exit: frame not on kstack %p kstack=%p",
418 frame, td->td_kstack);
423 _test_frame_exit(struct trapframe *frame)
425 thread_t td = curthread;
427 if (ISPL(frame->tf_cs) == SEL_UPL) {
428 KKASSERT(td->td_lwp);
429 KASSERT(td->td_lwp->lwp_md.md_regs == frame,
430 ("_test_frame_exit: Frame mismatch %p %p",
431 td->td_lwp->lwp_md.md_regs, frame));
432 if (td->td_lwp->lwp_saveusp != (void *)frame->tf_rsp) {
433 kprintf("_test_frame_exit: %s:%d usp mismatch %p/%p\n",
434 td->td_comm, td->td_proc->p_pid,
435 td->td_lwp->lwp_saveusp,
436 (void *)frame->tf_rsp);
438 if (td->td_lwp->lwp_saveupc != (void *)frame->tf_rip) {
439 kprintf("_test_frame_exit: %s:%d upc mismatch %p/%p\n",
440 td->td_comm, td->td_proc->p_pid,
441 td->td_lwp->lwp_saveupc,
442 (void *)frame->tf_rip);
446 * adulterate the fields to catch entries that
447 * don't run through test_frame_enter
449 td->td_lwp->lwp_saveusp =
450 (void *)~(intptr_t)td->td_lwp->lwp_saveusp;
451 td->td_lwp->lwp_saveupc =
452 (void *)~(intptr_t)td->td_lwp->lwp_saveupc;
454 if ((char *)frame < td->td_kstack ||
455 (char *)frame > td->td_kstack + td->td_kstack_size) {
456 panic("_test_frame_exit: frame not on kstack %p kstack=%p",
457 frame, td->td_kstack);