C++ Debugger函数代码示例

int
prom_cngetc(dev_t dev)
{
	unsigned char ch = '\0';
	int l;
#ifdef DDB
	static int nplus = 0;
#endif
	
	while ((l = OF_read(stdin, &ch, 1)) != 1)
		/* void */;
#ifdef DDB
	if (ch == '+') {
		if (nplus++ > 3)
			Debugger();
	} else
		nplus = 0;
#endif
	if (ch == '\r')
		ch = '\n';
	if (ch == '\b')
		ch = '\177';
	return ch;
}

/*
 * Report critical errors.  ip may be NULL.
 */
void
hammer_critical_error(hammer_mount_t hmp, hammer_inode_t ip,
		      int error, const char *msg)
{
	hmp->flags |= HAMMER_MOUNT_CRITICAL_ERROR;

	krateprintf(&hmp->krate,
		    "HAMMER(%s): Critical error inode=%jd error=%d %s\n",
		    hmp->mp->mnt_stat.f_mntfromname,
		    (intmax_t)(ip ? ip->obj_id : -1),
		    error, msg);

	if (hmp->ronly == 0) {
		hmp->ronly = 2;		/* special errored read-only mode */
		hmp->mp->mnt_flag |= MNT_RDONLY;
		RB_SCAN(hammer_vol_rb_tree, &hmp->rb_vols_root, NULL,
			hammer_adjust_volume_mode, NULL);
		kprintf("HAMMER(%s): Forcing read-only mode\n",
			hmp->mp->mnt_stat.f_mntfromname);
	}
	hmp->error = error;
	if (hammer_debug_critical)
		Debugger("Entering debugger");
}

/*
 * Obtain a shared lock
 *
 * We do not give pending exclusive locks priority over shared locks as
 * doing so could lead to a deadlock.
 */
void
hammer_lock_sh(struct hammer_lock *lock)
{
	thread_t td = curthread;
	u_int lv;
	u_int nlv;
	const char *ident = "hmrlck";

	KKASSERT(lock->refs);
	for (;;) {
		lv = lock->lockval;

		if ((lv & HAMMER_LOCKF_EXCLUSIVE) == 0) {
			nlv = (lv + 1);
			if (atomic_cmpset_int(&lock->lockval, lv, nlv))
				break;
		} else if (lock->lowner == td) {
			/*
			 * Disallowed case, drop into kernel debugger for
			 * now.  A cont continues w/ an exclusive lock.
			 */
			nlv = (lv + 1);
			if (atomic_cmpset_int(&lock->lockval, lv, nlv)) {
				if (hammer_debug_critical)
					Debugger("hammer_lock_sh: holding ex");
				break;
			}
		} else {
			nlv = lv | HAMMER_LOCKF_WANTED;
			++hammer_contention_count;
			tsleep_interlock(&lock->lockval, 0);
			if (atomic_cmpset_int(&lock->lockval, lv, nlv))
				tsleep(&lock->lockval, PINTERLOCKED, ident, 0);
		}
	}
}

void
cpu_boot_secondary(struct cpu_info *ci)
{
	struct pcb *pcb;
	int i;
	struct pmap *kpm = pmap_kernel();
	extern u_int32_t mp_pdirpa;

	if (mp_verbose)
		printf("%s: starting", ci->ci_dev.dv_xname);

	/* XXX move elsewhere, not per CPU. */
	mp_pdirpa = kpm->pm_pdirpa;

	pcb = ci->ci_idle_pcb;

	if (mp_verbose)
		printf(", init idle stack ptr is 0x%x\n", pcb->pcb_esp);

	CPU_STARTUP(ci);

	/*
	 * wait for it to become ready
	 */
	for (i = 100000; (!(ci->ci_flags & CPUF_RUNNING)) && i > 0; i--) {
		delay(10);
	}
	if (!(ci->ci_flags & CPUF_RUNNING)) {
		printf("%s failed to become ready\n", ci->ci_dev.dv_xname);
#ifdef DDB
		Debugger();
#endif
	}

	CPU_START_CLEANUP(ci);
}

boolean_t
lck_rw_lock_shared_to_exclusive(
	lck_rw_t	*lck)
{
	int	    i;
	boolean_t	    do_wakeup = FALSE;
	wait_result_t      res;
#if	MACH_LDEBUG
	int		   decrementer;
#endif	/* MACH_LDEBUG */
	boolean_t	istate;
#if	CONFIG_DTRACE
	uint64_t wait_interval = 0;
	int slept = 0;
	int readers_at_sleep = 0;
#endif

	istate = lck_interlock_lock(lck);

	lck->lck_rw_shared_count--;	

	if (lck->lck_rw_want_upgrade) {
		KERNEL_DEBUG(MACHDBG_CODE(DBG_MACH_LOCKS, LCK_RW_LCK_SH_TO_EX_CODE) | DBG_FUNC_START,
			     (int)lck, lck->lck_rw_shared_count, lck->lck_rw_want_upgrade, 0, 0);

		/*
		 *	Someone else has requested upgrade.
		 *	Since we've released a read lock, wake
		 *	him up.
		 */
		if (lck->lck_w_waiting && (lck->lck_rw_shared_count == 0)) {
			lck->lck_w_waiting = FALSE;
			do_wakeup = TRUE;
		}

		lck_interlock_unlock(lck, istate);

		if (do_wakeup) 
			thread_wakeup(RW_LOCK_WRITER_EVENT(lck));

		KERNEL_DEBUG(MACHDBG_CODE(DBG_MACH_LOCKS, LCK_RW_LCK_SH_TO_EX_CODE) | DBG_FUNC_END,
			     (int)lck, lck->lck_rw_shared_count, lck->lck_rw_want_upgrade, 0, 0);

		return (FALSE);
	}

	lck->lck_rw_want_upgrade = TRUE;

#if	MACH_LDEBUG
	decrementer = DECREMENTER_TIMEOUT;
#endif	/* MACH_LDEBUG */
	while (lck->lck_rw_shared_count != 0) {
#if	CONFIG_DTRACE
		if (lockstat_probemap[LS_LCK_RW_LOCK_SHARED_TO_EXCL_SPIN] && wait_interval == 0) {
			wait_interval = mach_absolute_time();
			readers_at_sleep = lck->lck_rw_shared_count;
		} else {
			wait_interval = -1;
		}
#endif
		i = lock_wait_time[lck->lck_rw_can_sleep ? 1 : 0];

		KERNEL_DEBUG(MACHDBG_CODE(DBG_MACH_LOCKS, LCK_RW_LCK_SH_TO_EX1_CODE) | DBG_FUNC_START,
			     (int)lck, lck->lck_rw_shared_count, i, 0, 0);

		if (i != 0) {
			lck_interlock_unlock(lck, istate);
#if	MACH_LDEBUG
			if (!--decrementer)
				Debugger("timeout - lck_rw_shared_count");
#endif	/* MACH_LDEBUG */
			while (--i != 0 && lck->lck_rw_shared_count != 0)
				lck_rw_lock_pause(istate);
			istate = lck_interlock_lock(lck);
		}

		if (lck->lck_rw_can_sleep && lck->lck_rw_shared_count != 0) {
			lck->lck_w_waiting = TRUE;
			res = assert_wait(RW_LOCK_WRITER_EVENT(lck), THREAD_UNINT);
			if (res == THREAD_WAITING) {
				lck_interlock_unlock(lck, istate);
				res = thread_block(THREAD_CONTINUE_NULL);
#if	CONFIG_DTRACE
				slept = 1;
#endif
				istate = lck_interlock_lock(lck);
			}
		}
		KERNEL_DEBUG(MACHDBG_CODE(DBG_MACH_LOCKS, LCK_RW_LCK_SH_TO_EX1_CODE) | DBG_FUNC_END,
			     (int)lck, lck->lck_rw_shared_count, 0, 0, 0);
	}

	lck_interlock_unlock(lck, istate);
#if	CONFIG_DTRACE
	/*
	 * We infer whether we took the sleep/spin path above by checking readers_at_sleep.
	 */
	if (wait_interval != 0 && wait_interval != (unsigned) -1 && readers_at_sleep) {
		if (slept == 0) {
			LOCKSTAT_RECORD2(LS_LCK_RW_LOCK_SHARED_TO_EXCL_SPIN, lck, mach_absolute_time() - wait_interval, 0);
//.........这里部分代码省略.........

void Stop()
{
  Debugging = 1;
  Debugger();
}

//.........这里部分代码省略.........
		if (xgd && xgd != gd) {
			crit_enter();
			++mycpu->gd_trap_nesting_level;
			if (mycpu->gd_trap_nesting_level < 25) {
				kprintf("SECONDARY PANIC ON CPU %d THREAD %p\n",
					mycpu->gd_cpuid, td);
			}
			td->td_release = NULL;	/* be a grinch */
			for (;;) {
				lwkt_deschedule_self(td);
				lwkt_switch();
			}
			/* NOT REACHED */
			/* --mycpu->gd_trap_nesting_level */
			/* crit_exit() */
		}

		/*
		 * Reentrant panic
		 */
		if (xgd && xgd == gd)
			break;

		/*
		 * We got it
		 */
		if (atomic_cmpset_ptr(&panic_cpu_gd, NULL, gd))
			break;
	}
#else
	panic_cpu_gd = gd;
#endif
	/*
	 * Try to get the system into a working state.  Save information
	 * we are about to destroy.
	 */
	kvcreinitspin();
	if (panicstr == NULL) {
		bcopy(td->td_toks_array, panic_tokens, sizeof(panic_tokens));
		panic_tokens_count = td->td_toks_stop - &td->td_toks_base;
	}
	lwkt_relalltokens(td);
	td->td_toks_stop = &td->td_toks_base;

	/*
	 * Setup
	 */
	bootopt = RB_AUTOBOOT | RB_DUMP;
	if (sync_on_panic == 0)
		bootopt |= RB_NOSYNC;
	newpanic = 0;
	if (panicstr) {
		bootopt |= RB_NOSYNC;
	} else {
		panicstr = fmt;
		newpanic = 1;
	}

	/*
	 * Format the panic string.
	 */
	__va_start(ap, fmt);
	kvsnprintf(buf, sizeof(buf), fmt, ap);
	if (panicstr == fmt)
		panicstr = buf;
	__va_end(ap);
	kprintf("panic: %s\n", buf);
#ifdef SMP
	/* two separate prints in case of an unmapped page and trap */
	kprintf("cpuid = %d\n", mycpu->gd_cpuid);
#endif

#if (NGPIO > 0) && defined(ERROR_LED_ON_PANIC)
	led_switch("error", 1);
#endif

#if defined(WDOG_DISABLE_ON_PANIC) && defined(WATCHDOG_ENABLE)
	wdog_disable();
#endif

	/*
	 * Enter the debugger or fall through & dump.  Entering the
	 * debugger will stop cpus.  If not entering the debugger stop
	 * cpus here.
	 */
#if defined(DDB)
	if (newpanic && trace_on_panic)
		print_backtrace(-1);
	if (debugger_on_panic)
		Debugger("panic");
	else
#endif
#ifdef SMP
	if (newpanic)
		stop_cpus(mycpu->gd_other_cpus);
#else
	;
#endif
	boot(bootopt);
}

/*
 * Shift *chainp up to the specified directory, change the filename
 * to "0xINODENUMBER", and adjust the key.  The chain becomes the
 * invisible hardlink target.
 *
 * The original *chainp has already been marked deleted.
 */
static
void
hammer2_hardlink_shiftup(hammer2_trans_t *trans, hammer2_chain_t **chainp,
			hammer2_inode_t *dip, hammer2_chain_t **dchainp,
			int nlinks, int *errorp)
{
	hammer2_inode_data_t *nipdata;
	hammer2_chain_t *chain;
	hammer2_chain_t *xchain;
	hammer2_key_t key_dummy;
	hammer2_key_t lhc;
	hammer2_blockref_t bref;
	int cache_index = -1;

	chain = *chainp;
	lhc = chain->data->ipdata.inum;
	KKASSERT((lhc & HAMMER2_DIRHASH_VISIBLE) == 0);

	/*
	 * Locate the inode or indirect block to create the new
	 * entry in.  lhc represents the inode number so there is
	 * no collision iteration.
	 *
	 * There should be no key collisions with invisible inode keys.
	 *
	 * WARNING! Must use inode_lock_ex() on dip to handle a stale
	 *	    dip->chain cache.
	 */
retry:
	*errorp = 0;
	xchain = hammer2_chain_lookup(dchainp, &key_dummy,
				      lhc, lhc, &cache_index, 0);
	if (xchain) {
		kprintf("X3 chain %p dip %p dchain %p dip->chain %p\n",
			xchain, dip, *dchainp, dip->chain);
		hammer2_chain_unlock(xchain);
		xchain = NULL;
		*errorp = ENOSPC;
#if 0
		Debugger("X3");
#endif
	}

	/*
	 * Create entry in common parent directory using the seek position
	 * calculated above.
	 *
	 * We must refactor chain because it might have been shifted into
	 * an indirect chain by the create.
	 */
	if (*errorp == 0) {
		KKASSERT(xchain == NULL);
#if 0
		*errorp = hammer2_chain_create(trans, dchainp, &xchain,
					       lhc, 0,
					       HAMMER2_BREF_TYPE_INODE,/* n/a */
					       HAMMER2_INODE_BYTES);   /* n/a */
#endif
		/*XXX this somehow isn't working on chain XXX*/
		/*KKASSERT(xxx)*/
	}

	/*
	 * Cleanup and handle retries.
	 */
	if (*errorp == EAGAIN) {
		kprintf("R");
		hammer2_chain_wait(*dchainp);
		hammer2_chain_drop(*dchainp);
		goto retry;
	}

	/*
	 * Handle the error case
	 */
	if (*errorp) {
		panic("error2");
		KKASSERT(xchain == NULL);
		return;
	}

	/*
	 * Use xchain as a placeholder for (lhc).  Duplicate chain to the
	 * same target bref as xchain and then delete xchain.  The duplication
	 * occurs after xchain in flush order even though xchain is deleted
	 * after the duplication. XXX
	 *
	 * WARNING! Duplications (to a different parent) can cause indirect
	 *	    blocks to be inserted, refactor xchain.
	 */
	bref = chain->bref;
	bref.key = lhc;			/* invisible dir entry key */
	bref.keybits = 0;
//.........这里部分代码省略.........

/* ARGSUSED */
int
compat_16_netbsd32___sigreturn14(struct lwp *l, const struct compat_16_netbsd32___sigreturn14_args *uap, register_t *retval)
{
	/* {
		syscallarg(struct sigcontext *) sigcntxp;
	} */
	struct netbsd32_sigcontext sc, *scp;
	struct trapframe64 *tf;
	struct proc *p = l->l_proc;

	/* First ensure consistent stack state (see sendsig). */
	write_user_windows();
	if (rwindow_save(l)) {
#ifdef DEBUG
		printf("netbsd32_sigreturn14: rwindow_save(%p) failed, sending SIGILL\n", p);
		Debugger();
#endif
		mutex_enter(p->p_lock);
		sigexit(l, SIGILL);
	}
#ifdef DEBUG
	if (sigdebug & SDB_FOLLOW) {
		printf("netbsd32_sigreturn14: %s[%d], sigcntxp %p\n",
		    p->p_comm, p->p_pid, SCARG(uap, sigcntxp));
		if (sigdebug & SDB_DDB) Debugger();
	}
#endif
	scp = (struct netbsd32_sigcontext *)(u_long)SCARG(uap, sigcntxp);
 	if ((vaddr_t)scp & 3 || (copyin((void *)scp, &sc, sizeof sc) != 0))
	{
#ifdef DEBUG
		printf("netbsd32_sigreturn14: copyin failed: scp=%p\n", scp);
		Debugger();
#endif
		return (EINVAL);
	}
	scp = ≻

	tf = l->l_md.md_tf;
	/*
	 * Only the icc bits in the psr are used, so it need not be
	 * verified.  pc and npc must be multiples of 4.  This is all
	 * that is required; if it holds, just do it.
	 */
	if (((sc.sc_pc | sc.sc_npc) & 3) != 0 || (sc.sc_pc == 0) || (sc.sc_npc == 0))
#ifdef DEBUG
	{
		printf("netbsd32_sigreturn14: pc %p or npc %p invalid\n", sc.sc_pc, sc.sc_npc);
		Debugger();
		return (EINVAL);
	}
#else
		return (EINVAL);
#endif
	/* take only psr ICC field */
	tf->tf_tstate = (int64_t)(tf->tf_tstate & ~TSTATE_CCR) | PSRCC_TO_TSTATE(sc.sc_psr);
	tf->tf_pc = (int64_t)sc.sc_pc;
	tf->tf_npc = (int64_t)sc.sc_npc;
	tf->tf_global[1] = (int64_t)sc.sc_g1;
	tf->tf_out[0] = (int64_t)sc.sc_o0;
	tf->tf_out[6] = (int64_t)sc.sc_sp;
#ifdef DEBUG
	if (sigdebug & SDB_FOLLOW) {
		printf("netbsd32_sigreturn14: return trapframe pc=%p sp=%p tstate=%llx\n",
		       (vaddr_t)tf->tf_pc, (vaddr_t)tf->tf_out[6], tf->tf_tstate);
		if (sigdebug & SDB_DDB) Debugger();
	}
#endif

	/* Restore signal stack. */
	mutex_enter(p->p_lock);
	if (sc.sc_onstack & SS_ONSTACK)
		l->l_sigstk.ss_flags |= SS_ONSTACK;
	else
		l->l_sigstk.ss_flags &= ~SS_ONSTACK;
	/* Restore signal mask. */
	(void) sigprocmask1(l, SIG_SETMASK, &sc.sc_mask, 0);
	mutex_exit(p->p_lock);

	return (EJUSTRETURN);
}

//.........这里部分代码省略.........

	/*
	 * Last chance to call the BIOS. Wiping the TLB means the BIOS' data
	 * areas are demapped on most systems.
	 */
	delay(20*1000);		/* Let any UART FIFO drain... */

	sys_config.cpu[0].tlbwired = UPAGES / 2;
	tlb_set_wired(0);
	tlb_flush(sys_config.cpu[0].tlbsize);
	tlb_set_wired(sys_config.cpu[0].tlbwired);

	/*
	 * Get a console, very early but after initial mapping setup.
	 */
	consinit();
	printf("Initial setup done, switching console.\n");

	/*
	 * Init message buffer.
	 */
	msgbufbase = (caddr_t)pmap_steal_memory(MSGBUFSIZE, NULL,NULL);
	initmsgbuf(msgbufbase, MSGBUFSIZE);

	/*
	 * Allocate U page(s) for proc[0], pm_tlbpid 1.
	 */
	proc0.p_addr = proc0paddr = curprocpaddr =
	    (struct user *)pmap_steal_memory(USPACE, NULL, NULL);
	proc0.p_md.md_regs = (struct trap_frame *)&proc0paddr->u_pcb.pcb_regs;
	tlb_set_pid(1);

	/*
	 * Allocate system data structures.
	 */
	i = (vsize_t)allocsys(NULL);
	sd = (caddr_t)pmap_steal_memory(i, NULL, NULL);
	allocsys(sd);

	/*
	 * Bootstrap VM system.
	 */
	pmap_bootstrap();

	/*
	 * Copy down exception vector code.
	 */
	bcopy(exception, (char *)CACHE_ERR_EXC_VEC, e_exception - exception);
	bcopy(exception, (char *)GEN_EXC_VEC, e_exception - exception);

	/*
	 * Build proper TLB refill handler trampolines.
	 */
	switch (cputype) {
	case MIPS_R5000:
		/*
		 * R5000 processors need a specific chip bug workaround
		 * in their tlb handlers.  Theoretically only revision 1
		 * of the processor need it, but there is evidence
		 * later versions also need it.
		 *
		 * This is also necessary on RM52x0; we test on the `rounded'
		 * cputype value instead of sys_config.cpu[0].type; this
		 * causes RM7k and RM9k to be included, just to be on the
		 * safe side.
		 */
		tlb_handler = (vaddr_t)&tlb_miss_err_r5k;
		xtlb_handler = (vaddr_t)&xtlb_miss_err_r5k;
		break;
	default:
		tlb_handler = (vaddr_t)&tlb_miss;
		xtlb_handler = (vaddr_t)&xtlb_miss;
		break;
	}

	build_trampoline(TLB_MISS_EXC_VEC, tlb_handler);
	build_trampoline(XTLB_MISS_EXC_VEC, xtlb_handler);

	/*
	 * Turn off bootstrap exception vectors.
	 */
	setsr(getsr() & ~SR_BOOT_EXC_VEC);
	proc0.p_md.md_regs->sr = getsr();

	/*
	 * Clear out the I and D caches.
	 */
	Mips_SyncCache();

#ifdef DDB
	db_machine_init();
	if (boothowto & RB_KDB)
		Debugger();
#endif

	/*
	 * Return new stack pointer.
	 */
	return ((caddr_t)proc0paddr + USPACE - 64);
}

//.........这里部分代码省略.........
				    physmem += btoc(((int) len));
				    mem_clusters[mem_cluster_cnt].start =
					(long) start;
				    mem_clusters[mem_cluster_cnt].size =
					(long) len;
				    mem_cluster_cnt++;
				    added = 1;
				}
			}
			if (added)
				printf("added to map\n");
			else
				printf("not added to map\n");
			idx++;
		}

	} else {
		/*
		 * Handle the case of not being called from the firmware.
		 */
		/* XXX hardwire to 32MB; should be kernel config option */
		physmem = 32 * 1024 * 1024 / 4096;
		mem_clusters[0].start = 0;
		mem_clusters[0].size = ctob(physmem);
		mem_cluster_cnt = 1;
	}


	for (i = 0; i < sizeof(bootinfo.boot_flags); i++) {
		switch (bootinfo.boot_flags[i]) {
		case '\0':
			break;
		case ' ':
			continue;
		case '-':
			while (bootinfo.boot_flags[i] != ' ' &&
			    bootinfo.boot_flags[i] != '\0') {
				switch (bootinfo.boot_flags[i]) {
				case 'a':
					boothowto |= RB_ASKNAME;
					break;
				case 'd':
					boothowto |= RB_KDB;
					break;
				case 's':
					boothowto |= RB_SINGLE;
					break;
				}
				i++;
			}
		}
	}

	/*
	 * Load the rest of the available pages into the VM system.
	 * The first chunk is tricky because we have to avoid the
	 * kernel, but the rest are easy.
	 */
	first = round_page(MIPS_KSEG0_TO_PHYS(kernend));
	last = mem_clusters[0].start + mem_clusters[0].size;
	uvm_page_physload(atop(first), atop(last), atop(first), atop(last),
		VM_FREELIST_DEFAULT);

	for (i = 1; i < mem_cluster_cnt; i++) {
		first = round_page(mem_clusters[i].start);
		last = mem_clusters[i].start + mem_clusters[i].size;
		uvm_page_physload(atop(first), atop(last), atop(first),
		    atop(last), VM_FREELIST_DEFAULT);
	}

	/*
	 * Initialize error message buffer (at end of core).
	 */
	mips_init_msgbuf();

	/*
	 * Allocate space for proc0's USPACE
	 */
	p0 = (void *)pmap_steal_memory(USPACE, NULL, NULL);
	lwp0.l_addr = proc0paddr = (struct user *)p0;
	lwp0.l_md.md_regs = (struct frame *)((char *)p0 + USPACE) - 1;
	proc0paddr->u_pcb.pcb_context[11] =
	    MIPS_INT_MASK | MIPS_SR_INT_IE; /* SR */

	pmap_bootstrap();

	/*
	 * Initialize debuggers, and break into them, if appropriate.
	 */
#if NKSYMS || defined(DDB) || defined(LKM)
	ksyms_init(((uintptr_t)ksym_end - (uintptr_t)ksym_start),
	    ksym_start, ksym_end);
#endif

	if (boothowto & RB_KDB) {
#if defined(DDB)
		Debugger();
#endif
	}
}

//.........这里部分代码省略.........

		if (vm == NULL) {
			fault_flags = -1;
			ftype = -1;
			goto nogo;
		}

		/*
		 * Debugging, try to catch kernel faults on the user address
		 * space when not inside on onfault (e.g. copyin/copyout)
		 * routine.
		 */
		if (usermode == 0 && (td->td_pcb == NULL ||
		    td->td_pcb->pcb_onfault == NULL)) {
#ifdef DDB
			if (freeze_on_seg_fault) {
				kprintf("trap_pfault: user address fault from kernel mode "
					"%016lx\n", (long)frame->tf_addr);
				while (freeze_on_seg_fault)
					    tsleep(&freeze_on_seg_fault, 0, "frzseg", hz * 20);
			}
#endif
		}
		map = &vm->vm_map;
	}

	/*
	 * PGEX_I is defined only if the execute disable bit capability is
	 * supported and enabled.
	 */
	if (frame->tf_err & PGEX_W)
		ftype = VM_PROT_WRITE;
	else if (frame->tf_err & PGEX_I)
		ftype = VM_PROT_EXECUTE;
	else
		ftype = VM_PROT_READ;

	if (map != &kernel_map) {
		/*
		 * Keep swapout from messing with us during this
		 *	critical time.
		 */
		PHOLD(lp->lwp_proc);

		/*
		 * Issue fault
		 */
		fault_flags = 0;
		if (usermode)
			fault_flags |= VM_FAULT_BURST | VM_FAULT_USERMODE;
		if (ftype & VM_PROT_WRITE)
			fault_flags |= VM_FAULT_DIRTY;
		else
			fault_flags |= VM_FAULT_NORMAL;
		rv = vm_fault(map, va, ftype, fault_flags);

		PRELE(lp->lwp_proc);
	} else {
		/*
		 * Don't have to worry about process locking or stacks in the
		 * kernel.
		 */
		fault_flags = VM_FAULT_NORMAL;
		rv = vm_fault(map, va, ftype, VM_FAULT_NORMAL);
	}
	if (rv == KERN_SUCCESS)
		return (0);
nogo:
	if (!usermode) {
		/*
		 * NOTE: in 64-bit mode traps push rsp/ss
		 *	 even if no ring change occurs.
		 */
		if (td->td_pcb->pcb_onfault &&
		    td->td_pcb->pcb_onfault_sp == frame->tf_rsp &&
		    td->td_gd->gd_intr_nesting_level == 0) {
			frame->tf_rip = (register_t)td->td_pcb->pcb_onfault;
			return (0);
		}
		trap_fatal(frame, frame->tf_addr);
		return (-1);
	}

	/*
	 * NOTE: on x86_64 we have a tf_addr field in the trapframe, no
	 * kludge is needed to pass the fault address to signal handlers.
	 */
	p = td->td_proc;
#ifdef DDB
	if (td->td_lwp->lwp_vkernel == NULL) {
		while (freeze_on_seg_fault) {
			tsleep(p, 0, "freeze", hz * 20);
		}
		if (ddb_on_seg_fault)
			Debugger("ddb_on_seg_fault");
	}
#endif

	return((rv == KERN_PROTECTION_FAILURE) ? SIGBUS : SIGSEGV);
}

//.........这里部分代码省略.........
	if (!usermode) {
		if (td->td_gd->gd_intr_nesting_level == 0 &&
		    td->td_pcb->pcb_onfault) {
			frame->tf_rip = (register_t)td->td_pcb->pcb_onfault;
			return (0);
		}
		trap_fatal(frame, frame->tf_addr);
		return (-1);
	}

	/*
	 * NOTE: on x86_64 we have a tf_addr field in the trapframe, no
	 * kludge is needed to pass the fault address to signal handlers.
	 */
	p = td->td_proc;
	if (td->td_lwp->lwp_vkernel == NULL) {
#ifdef DDB
		if (bootverbose || freeze_on_seg_fault || ddb_on_seg_fault) {
#else
		if (bootverbose) {
#endif
			kprintf("seg-fault ft=%04x ff=%04x addr=%p rip=%p "
			    "pid=%d cpu=%d p_comm=%s\n",
			    ftype, fault_flags,
			    (void *)frame->tf_addr,
			    (void *)frame->tf_rip,
			    p->p_pid, mycpu->gd_cpuid, p->p_comm);
		}
#ifdef DDB
		while (freeze_on_seg_fault) {
			tsleep(p, 0, "freeze", hz * 20);
		}
		if (ddb_on_seg_fault)
			Debugger("ddb_on_seg_fault");
#endif
	}

	return((rv == KERN_PROTECTION_FAILURE) ? SIGBUS : SIGSEGV);
}

static void
trap_fatal(struct trapframe *frame, vm_offset_t eva)
{
	int code, ss;
	u_int type;
	long rsp;
	struct soft_segment_descriptor softseg;
	char *msg;

	code = frame->tf_err;
	type = frame->tf_trapno;
	sdtossd(&gdt[IDXSEL(frame->tf_cs & 0xffff)], &softseg);

	if (type <= MAX_TRAP_MSG)
		msg = trap_msg[type];
	else
		msg = "UNKNOWN";
	kprintf("\n\nFatal trap %d: %s while in %s mode\n", type, msg,
	    ISPL(frame->tf_cs) == SEL_UPL ? "user" : "kernel");
#ifdef SMP
	/* three separate prints in case of a trap on an unmapped page */
	kprintf("cpuid = %d; ", mycpu->gd_cpuid);
	kprintf("lapic->id = %08x\n", lapic->id);
#endif
	if (type == T_PAGEFLT) {
		kprintf("fault virtual address	= 0x%lx\n", eva);

/* ioctl routine */
int
vinumioctl(dev_t dev,
    u_long cmd,
    caddr_t data,
    int flag,
    struct thread *td)
{
    unsigned int objno;
    int error = 0;
    struct sd *sd;
    struct plex *plex;
    struct volume *vol;
    unsigned int index;					    /* for transferring config info */
    unsigned int sdno;					    /* for transferring config info */
    int fe;						    /* free list element number */
    struct _ioctl_reply *ioctl_reply = (struct _ioctl_reply *) data; /* struct to return */

    /* First, decide what we're looking at */
    switch (DEVTYPE(dev)) {
    case VINUM_SUPERDEV_TYPE:				    /* ordinary super device */
	ioctl_reply = (struct _ioctl_reply *) data;	    /* save the address to reply to */
	switch (cmd) {
#ifdef VINUMDEBUG
	case VINUM_DEBUG:
	    if (((struct debuginfo *) data)->changeit)	    /* change debug settings */
		debug = (((struct debuginfo *) data)->param);
	    else {
		if (debug & DEBUG_REMOTEGDB)
		    boothowto |= RB_GDB;		    /* serial debug line */
		else
		    boothowto &= ~RB_GDB;		    /* local ddb */
		Debugger("vinum debug");
	    }
	    ioctl_reply = (struct _ioctl_reply *) data;	    /* reinstate the address to reply to */
	    ioctl_reply->error = 0;
	    return 0;
#endif

	case VINUM_CREATE:				    /* create a vinum object */
	    error = lock_config();			    /* get the config for us alone */
	    if (error)					    /* can't do it, */
		return error;				    /* give up */
	    error = setjmp(command_fail);		    /* come back here on error */
	    if (error == 0)				    /* first time, */
		ioctl_reply->error = parse_user_config((char *) data, /* update the config */
		    &keyword_set);
	    else if (ioctl_reply->error == 0) {		    /* longjmp, but no error status */
		ioctl_reply->error = EINVAL;		    /* note that something's up */
		ioctl_reply->msg[0] = '\0';		    /* no message? */
	    }
	    unlock_config();
	    return 0;					    /* must be 0 to return the real error info */

	case VINUM_GETCONFIG:				    /* get the configuration information */
	    bcopy(&vinum_conf, data, sizeof(vinum_conf));
	    return 0;

	    /* start configuring the subsystem */
	case VINUM_STARTCONFIG:
	    return start_config(*(int *) data);		    /* just lock it.  Parameter is 'force' */

	    /*
	     * Move the individual parts of the config to user space.
	     *
	     * Specify the index of the object in the first word of data,
	     * and return the object there
	     */
	case VINUM_DRIVECONFIG:
	    index = *(int *) data;			    /* get the index */
	    if (index >= (unsigned) vinum_conf.drives_allocated) /* can't do it */
		return ENXIO;				    /* bang */
	    bcopy(&DRIVE[index], data, sizeof(struct _drive)); /* copy the config item out */
	    return 0;

	case VINUM_SDCONFIG:
	    index = *(int *) data;			    /* get the index */
	    if (index >= (unsigned) vinum_conf.subdisks_allocated) /* can't do it */
		return ENXIO;				    /* bang */
	    bcopy(&SD[index], data, sizeof(struct _sd));    /* copy the config item out */
	    return 0;

	case VINUM_PLEXCONFIG:
	    index = *(int *) data;			    /* get the index */
	    if (index >= (unsigned) vinum_conf.plexes_allocated) /* can't do it */
		return ENXIO;				    /* bang */
	    bcopy(&PLEX[index], data, sizeof(struct _plex)); /* copy the config item out */
	    return 0;

	case VINUM_VOLCONFIG:
	    index = *(int *) data;			    /* get the index */
	    if (index >= (unsigned) vinum_conf.volumes_allocated) /* can't do it */
		return ENXIO;				    /* bang */
	    bcopy(&VOL[index], data, sizeof(struct _volume)); /* copy the config item out */
	    return 0;

	case VINUM_PLEXSDCONFIG:
	    index = *(int *) data;			    /* get the plex index */
	    sdno = ((int *) data)[1];			    /* and the sd index */
	    if ((index >= (unsigned) vinum_conf.plexes_allocated) /* plex doesn't exist */
//.........这里部分代码省略.........

//.........这里部分代码省略.........
	 * and second level page tables.  Pages of memory will be allocated
	 * and mapped for other structures that are required for system
	 * operation.  When it returns, physical_freestart and free_pages will
	 * have been updated to reflect the allocations that were made.  In
	 * addition, kernel_l1pt, kernel_pt_table[], systempage, irqstack,
	 * abtstack, undstack, kernelstack, msgbufphys will be set to point to
	 * the memory that was allocated for them.
	 */
	setup_real_page_tables();

	/*
	 * Moved from cpu_startup() as data_abort_handler() references
	 * this during uvm init.
	 */
	proc0paddr = (struct user *)kernelstack.pv_va;
	lwp0.l_addr = proc0paddr;

#ifdef VERBOSE_INIT_ARM
	printf("bootstrap done.\n");
#endif

	arm32_vector_init(ARM_VECTORS_LOW, ARM_VEC_ALL);

	/*
	 * Pages were allocated during the secondary bootstrap for the
	 * stacks for different CPU modes.
	 * We must now set the r13 registers in the different CPU modes to
	 * point to these stacks.
	 * Since the ARM stacks use STMFD etc. we must set r13 to the top end
	 * of the stack memory.
	 */
#ifdef VERBOSE_INIT_ARM
	printf("init subsystems: stacks ");
#endif

	set_stackptr(PSR_IRQ32_MODE, irqstack.pv_va + IRQ_STACK_SIZE * PAGE_SIZE);
	set_stackptr(PSR_ABT32_MODE, abtstack.pv_va + ABT_STACK_SIZE * PAGE_SIZE);
	set_stackptr(PSR_UND32_MODE, undstack.pv_va + UND_STACK_SIZE * PAGE_SIZE);

	/*
	 * Well we should set a data abort handler.
	 * Once things get going this will change as we will need a proper
	 * handler.
	 * Until then we will use a handler that just panics but tells us
	 * why.
	 * Initialisation of the vectors will just panic on a data abort.
	 * This just fills in a slightly better one.
	 */
#ifdef VERBOSE_INIT_ARM
	printf("vectors ");
#endif
	data_abort_handler_address = (u_int)data_abort_handler;
	prefetch_abort_handler_address = (u_int)prefetch_abort_handler;
	undefined_handler_address = (u_int)undefinedinstruction_bounce;

	/* Initialise the undefined instruction handlers */
#ifdef VERBOSE_INIT_ARM
	printf("undefined ");
#endif
	undefined_init();

	/* Load memory into UVM. */
#ifdef VERBOSE_INIT_ARM
	printf("page ");
#endif
	uvm_setpagesize();        /* initialize PAGE_SIZE-dependent variables */
	uvm_page_physload(atop(physical_freestart), atop(physical_freeend),
	    atop(physical_freestart), atop(physical_freeend),
	    VM_FREELIST_DEFAULT);

	/* Boot strap pmap telling it where the kernel page table is */
#ifdef VERBOSE_INIT_ARM
	printf("pmap ");
#endif
	pmap_bootstrap(KERNEL_VM_BASE, KERNEL_VM_BASE + KERNEL_VM_SIZE);

#ifdef VERBOSE_INIT_ARM
	printf("done.\n");
#endif

#ifdef KGDB
	if (boothowto & RB_KDB) {
		kgdb_debug_init = 1;
		kgdb_connect(1);
	}
#endif

#ifdef DDB
	db_machine_init();

	/* Firmware doesn't load symbols. */
	ddb_init(0, NULL, NULL);

	if (boothowto & RB_KDB)
		Debugger();
#endif

	/* We return the new stack pointer address */
	return(kernelstack.pv_va + USPACE_SVC_STACK_TOP);
}