Move ast() and userret() to sys/kern/subr_trap.c now that they are MI.

1 files changed, 17 insertions, 1162 deletions

diff --git a/sys/kern/subr_trap.c b/sys/kern/subr_trap.c
index f6a9e0c..7ffc5ec 100644
--- a/sys/kern/subr_trap.c
+++ b/sys/kern/subr_trap.c
@@ -38,131 +38,27 @@
  * $FreeBSD$
  */
 
-/*
- * 386 Trap and System call handling
- */
-
-#include "opt_clock.h"
-#include "opt_cpu.h"
-#include "opt_ddb.h"
-#include "opt_isa.h"
-#include "opt_ktrace.h"
+#ifdef __i386__
 #include "opt_npx.h"
-#include "opt_trap.h"
+#endif
 
 #include <sys/param.h>
 #include <sys/bus.h>
-#include <sys/systm.h>
-#include <sys/proc.h>
-#include <sys/pioctl.h>
 #include <sys/kernel.h>
-#include <sys/ktr.h>
+#include <sys/lock.h>
 #include <sys/mutex.h>
+#include <sys/proc.h>
 #include <sys/resourcevar.h>
 #include <sys/signalvar.h>
-#include <sys/syscall.h>
-#include <sys/sysctl.h>
-#include <sys/sysent.h>
-#include <sys/uio.h>
+#include <sys/systm.h>
 #include <sys/vmmeter.h>
-#ifdef KTRACE
-#include <sys/ktrace.h>
-#endif
-
-#include <vm/vm.h>
-#include <vm/vm_param.h>
-#include <sys/lock.h>
-#include <vm/pmap.h>
-#include <vm/vm_kern.h>
-#include <vm/vm_map.h>
-#include <vm/vm_page.h>
-#include <vm/vm_extern.h>
-
 #include <machine/cpu.h>
-#include <machine/md_var.h>
 #include <machine/pcb.h>
-#ifdef SMP
-#include <machine/smp.h>
-#endif
-#include <machine/tss.h>
-
-#include <i386/isa/icu.h>
-#include <i386/isa/intr_machdep.h>
-
-#ifdef POWERFAIL_NMI
-#include <sys/syslog.h>
-#include <machine/clock.h>
-#endif
-
-#include <machine/vm86.h>
-
-#include <ddb/ddb.h>
-
-#include <sys/sysctl.h>
-
-int (*pmath_emulate) __P((struct trapframe *));
-
-extern void trap __P((struct trapframe frame));
-extern int trapwrite __P((unsigned addr));
-extern void syscall __P((struct trapframe frame));
-extern void ast __P((struct trapframe *framep));
-
-static int trap_pfault __P((struct trapframe *, int, vm_offset_t));
-static void trap_fatal __P((struct trapframe *, vm_offset_t));
-void dblfault_handler __P((void));
-
-extern inthand_t IDTVEC(lcall_syscall);
-
-#define MAX_TRAP_MSG		28
-static char *trap_msg[] = {
-	"",					/*  0 unused */
-	"privileged instruction fault",		/*  1 T_PRIVINFLT */
-	"",					/*  2 unused */
-	"breakpoint instruction fault",		/*  3 T_BPTFLT */
-	"",					/*  4 unused */
-	"",					/*  5 unused */
-	"arithmetic trap",			/*  6 T_ARITHTRAP */
-	"",					/*  7 unused */
-	"",					/*  8 unused */
-	"general protection fault",		/*  9 T_PROTFLT */
-	"trace trap",				/* 10 T_TRCTRAP */
-	"",					/* 11 unused */
-	"page fault",				/* 12 T_PAGEFLT */
-	"",					/* 13 unused */
-	"alignment fault",			/* 14 T_ALIGNFLT */
-	"",					/* 15 unused */
-	"",					/* 16 unused */
-	"",					/* 17 unused */
-	"integer divide fault",			/* 18 T_DIVIDE */
-	"non-maskable interrupt trap",		/* 19 T_NMI */
-	"overflow trap",			/* 20 T_OFLOW */
-	"FPU bounds check fault",		/* 21 T_BOUND */
-	"FPU device not available",		/* 22 T_DNA */
-	"double fault",				/* 23 T_DOUBLEFLT */
-	"FPU operand fetch fault",		/* 24 T_FPOPFLT */
-	"invalid TSS fault",			/* 25 T_TSSFLT */
-	"segment not present fault",		/* 26 T_SEGNPFLT */
-	"stack fault",				/* 27 T_STKFLT */
-	"machine check trap",			/* 28 T_MCHK */
-};
-
-#if defined(I586_CPU) && !defined(NO_F00F_HACK)
-extern int has_f00f_bug;
-#endif
-
-#ifdef DDB
-static int ddb_on_nmi = 1;
-SYSCTL_INT(_machdep, OID_AUTO, ddb_on_nmi, CTLFLAG_RW,
-	&ddb_on_nmi, 0, "Go to DDB on NMI");
-#endif
-static int panic_on_nmi = 1;
-SYSCTL_INT(_machdep, OID_AUTO, panic_on_nmi, CTLFLAG_RW,
-	&panic_on_nmi, 0, "Panic on NMI");
-
-#ifdef WITNESS
-extern char *syscallnames[];
-#endif
 
+/*
+ * Define the code needed before returning to user mode, for
+ * trap and syscall.
+ */
 void
 userret(p, frame, oticks)
 	struct proc *p;
@@ -180,12 +76,12 @@ userret(p, frame, oticks)
 	p->p_pri.pri_level = p->p_pri.pri_user;
 	if (resched_wanted(p)) {
 		/*
-		 * Since we are curproc, clock will normally just change
-		 * our priority without moving us from one queue to another
-		 * (since the running process is not on a queue.)
-		 * If that happened after we setrunqueue ourselves but before we
-		 * mi_switch()'ed, we might not be on the queue indicated by
-		 * our priority.
+		 * Since we are curproc, a clock interrupt could
+		 * change our priority without changing run queues
+		 * (the running process is not kept on a run queue).
+		 * If this happened after we setrunqueue ourselves but
+		 * before we switch()'ed, we might not be on the queue
+		 * indicated by our priority.
 		 */
 		DROP_GIANT_NOSWITCH();
 		setrunqueue(p);
@@ -212,1050 +108,9 @@ userret(p, frame, oticks)
 }
 
 /*
- * Exception, fault, and trap interface to the FreeBSD kernel.
- * This common code is called from assembly language IDT gate entry
- * routines that prepare a suitable stack frame, and restore this
- * frame after the exception has been processed.
- */
-
-void
-trap(frame)
-	struct trapframe frame;
-{
-	struct proc *p = curproc;
-	u_quad_t sticks = 0;
-	int i = 0, ucode = 0, type, code;
-	vm_offset_t eva;
-#ifdef POWERFAIL_NMI
-	static int lastalert = 0;
-#endif
-
-	atomic_add_int(&cnt.v_trap, 1);
-
-	if ((frame.tf_eflags & PSL_I) == 0) {
-		/*
-		 * Buggy application or kernel code has disabled
-		 * interrupts and then trapped.  Enabling interrupts
-		 * now is wrong, but it is better than running with
-		 * interrupts disabled until they are accidentally
-		 * enabled later.  XXX This is really bad if we trap
-		 * while holding a spin lock.
-		 */
-		type = frame.tf_trapno;
-		if (ISPL(frame.tf_cs) == SEL_UPL || (frame.tf_eflags & PSL_VM))
-			printf(
-			    "pid %ld (%s): trap %d with interrupts disabled\n",
-			    (long)curproc->p_pid, curproc->p_comm, type);
-		else if (type != T_BPTFLT && type != T_TRCTRAP) {
-			/*
-			 * XXX not quite right, since this may be for a
-			 * multiple fault in user mode.
-			 */
-			printf("kernel trap %d with interrupts disabled\n",
-			    type);
-			/*
-			 * We should walk p_heldmtx here and see if any are
-			 * spin mutexes, and not do this if so.
-			 */
-			enable_intr();
-		}
-	}
-
-	eva = 0;
-
-#if defined(I586_CPU) && !defined(NO_F00F_HACK)
-restart:
-#endif
-
-	type = frame.tf_trapno;
-	code = frame.tf_err;
-
-        if ((ISPL(frame.tf_cs) == SEL_UPL) ||
-	    ((frame.tf_eflags & PSL_VM) && !in_vm86call)) {
-		/* user trap */
-
-		mtx_lock_spin(&sched_lock);
-		sticks = p->p_sticks;
-		mtx_unlock_spin(&sched_lock);
-		p->p_frame = &frame;
-
-		switch (type) {
-		case T_PRIVINFLT:	/* privileged instruction fault */
-			ucode = type;
-			i = SIGILL;
-			break;
-
-		case T_BPTFLT:		/* bpt instruction fault */
-		case T_TRCTRAP:		/* trace trap */
-			frame.tf_eflags &= ~PSL_T;
-			i = SIGTRAP;
-			break;
-
-		case T_ARITHTRAP:	/* arithmetic trap */
-#ifdef DEV_NPX
-			ucode = npxtrap();
-			if (ucode == -1)
-				return;
-#else
-			ucode = code;
-#endif
-			i = SIGFPE;
-			break;
-
-			/*
-			 * The following two traps can happen in
-			 * vm86 mode, and, if so, we want to handle
-			 * them specially.
-			 */
-		case T_PROTFLT:		/* general protection fault */
-		case T_STKFLT:		/* stack fault */
-			if (frame.tf_eflags & PSL_VM) {
-				mtx_lock(&Giant);
-				i = vm86_emulate((struct vm86frame *)&frame);
-				mtx_unlock(&Giant);
-				if (i == 0)
-					goto user;
-				break;
-			}
-			/* FALL THROUGH */
-
-		case T_SEGNPFLT:	/* segment not present fault */
-		case T_TSSFLT:		/* invalid TSS fault */
-		case T_DOUBLEFLT:	/* double fault */
-		default:
-			ucode = code + BUS_SEGM_FAULT ;
-			i = SIGBUS;
-			break;
-
-		case T_PAGEFLT:		/* page fault */
-			/*
-			 * For some Cyrix CPUs, %cr2 is clobbered by
-			 * interrupts.  This problem is worked around by using
-			 * an interrupt gate for the pagefault handler.  We
-			 * are finally ready to read %cr2 and then must
-			 * reenable interrupts.
-			 */
-			eva = rcr2();
-			enable_intr();
-			mtx_lock(&Giant);
-			i = trap_pfault(&frame, TRUE, eva);
-			mtx_unlock(&Giant);
-#if defined(I586_CPU) && !defined(NO_F00F_HACK)
-			if (i == -2) {
-				/*
-				 * f00f hack workaround has triggered, treat
-				 * as illegal instruction not page fault.
-				 */
-				frame.tf_trapno = T_PRIVINFLT;
-				goto restart;
-			}
-#endif
-			if (i == -1)
-				goto out;
-			if (i == 0)
-				goto user;
-
-			ucode = T_PAGEFLT;
-			break;
-
-		case T_DIVIDE:		/* integer divide fault */
-			ucode = FPE_INTDIV;
-			i = SIGFPE;
-			break;
-
-#ifdef DEV_ISA
-		case T_NMI:
-#ifdef POWERFAIL_NMI
-#ifndef TIMER_FREQ
-#  define TIMER_FREQ 1193182
-#endif
-			mtx_lock(&Giant);
-			if (time_second - lastalert > 10) {
-				log(LOG_WARNING, "NMI: power fail\n");
-				sysbeep(TIMER_FREQ/880, hz);
-				lastalert = time_second;
-			}
-			mtx_unlock(&Giant);
-			goto out;
-#else /* !POWERFAIL_NMI */
-			/* machine/parity/power fail/"kitchen sink" faults */
-			/* XXX Giant */
-			if (isa_nmi(code) == 0) {
-#ifdef DDB
-				/*
-				 * NMI can be hooked up to a pushbutton
-				 * for debugging.
-				 */
-				if (ddb_on_nmi) {
-					printf ("NMI ... going to debugger\n");
-					kdb_trap (type, 0, &frame);
-				}
-#endif /* DDB */
-				goto out;
-			} else if (panic_on_nmi)
-				panic("NMI indicates hardware failure");
-			break;
-#endif /* POWERFAIL_NMI */
-#endif /* DEV_ISA */
-
-		case T_OFLOW:		/* integer overflow fault */
-			ucode = FPE_INTOVF;
-			i = SIGFPE;
-			break;
-
-		case T_BOUND:		/* bounds check fault */
-			ucode = FPE_FLTSUB;
-			i = SIGFPE;
-			break;
-
-		case T_DNA:
-#ifdef DEV_NPX
-			/* transparent fault (due to context switch "late") */
-			if (npxdna())
-				goto out;
-#endif
-			if (!pmath_emulate) {
-				i = SIGFPE;
-				ucode = FPE_FPU_NP_TRAP;
-				break;
-			}
-			mtx_lock(&Giant);
-			i = (*pmath_emulate)(&frame);
-			mtx_unlock(&Giant);
-			if (i == 0) {
-				if (!(frame.tf_eflags & PSL_T))
-					goto out;
-				frame.tf_eflags &= ~PSL_T;
-				i = SIGTRAP;
-			}
-			/* else ucode = emulator_only_knows() XXX */
-			break;
-
-		case T_FPOPFLT:		/* FPU operand fetch fault */
-			ucode = T_FPOPFLT;
-			i = SIGILL;
-			break;
-		}
-	} else {
-		/* kernel trap */
-
-		switch (type) {
-		case T_PAGEFLT:			/* page fault */
-			/*
-			 * For some Cyrix CPUs, %cr2 is clobbered by
-			 * interrupts.  This problem is worked around by using
-			 * an interrupt gate for the pagefault handler.  We
-			 * are finally ready to read %cr2 and then must
-			 * reenable interrupts.
-			 */
-			eva = rcr2();
-			enable_intr();
-			mtx_lock(&Giant);
-			(void) trap_pfault(&frame, FALSE, eva);
-			mtx_unlock(&Giant);
-			goto out;
-
-		case T_DNA:
-#ifdef DEV_NPX
-			/*
-			 * The kernel is apparently using npx for copying.
-			 * XXX this should be fatal unless the kernel has
-			 * registered such use.
-			 */
-			if (npxdna())
-				goto out;
-#endif
-			break;
-
-			/*
-			 * The following two traps can happen in
-			 * vm86 mode, and, if so, we want to handle
-			 * them specially.
-			 */
-		case T_PROTFLT:		/* general protection fault */
-		case T_STKFLT:		/* stack fault */
-			if (frame.tf_eflags & PSL_VM) {
-				mtx_lock(&Giant);
-				i = vm86_emulate((struct vm86frame *)&frame);
-				mtx_unlock(&Giant);
-				if (i != 0)
-					/*
-					 * returns to original process
-					 */
-					vm86_trap((struct vm86frame *)&frame);
-				goto out;
-			}
-			if (type == T_STKFLT)
-				break;
-
-			/* FALL THROUGH */
-
-		case T_SEGNPFLT:	/* segment not present fault */
-			if (in_vm86call)
-				break;
-
-			if (p->p_intr_nesting_level != 0)
-				break;
-
-			/*
-			 * Invalid %fs's and %gs's can be created using
-			 * procfs or PT_SETREGS or by invalidating the
-			 * underlying LDT entry.  This causes a fault
-			 * in kernel mode when the kernel attempts to
-			 * switch contexts.  Lose the bad context
-			 * (XXX) so that we can continue, and generate
-			 * a signal.
-			 */
-			if (frame.tf_eip == (int)cpu_switch_load_gs) {
-				PCPU_GET(curpcb)->pcb_gs = 0;
-				PROC_LOCK(p);
-				psignal(p, SIGBUS);
-				PROC_UNLOCK(p);
-				goto out;
-			}
-
-			/*
-			 * Invalid segment selectors and out of bounds
-			 * %eip's and %esp's can be set up in user mode.
-			 * This causes a fault in kernel mode when the
-			 * kernel tries to return to user mode.  We want
-			 * to get this fault so that we can fix the
-			 * problem here and not have to check all the
-			 * selectors and pointers when the user changes
-			 * them.
-			 */
-			if (frame.tf_eip == (int)doreti_iret) {
-				frame.tf_eip = (int)doreti_iret_fault;
-				goto out;
-			}
-			if (frame.tf_eip == (int)doreti_popl_ds) {
-				frame.tf_eip = (int)doreti_popl_ds_fault;
-				goto out;
-			}
-			if (frame.tf_eip == (int)doreti_popl_es) {
-				frame.tf_eip = (int)doreti_popl_es_fault;
-				goto out;
-			}
-			if (frame.tf_eip == (int)doreti_popl_fs) {
-				frame.tf_eip = (int)doreti_popl_fs_fault;
-				goto out;
-			}
-			if (PCPU_GET(curpcb) != NULL &&
-			    PCPU_GET(curpcb)->pcb_onfault != NULL) {
-				frame.tf_eip =
-				    (int)PCPU_GET(curpcb)->pcb_onfault;
-				goto out;
-			}
-			break;
-
-		case T_TSSFLT:
-			/*
-			 * PSL_NT can be set in user mode and isn't cleared
-			 * automatically when the kernel is entered.  This
-			 * causes a TSS fault when the kernel attempts to
-			 * `iret' because the TSS link is uninitialized.  We
-			 * want to get this fault so that we can fix the
-			 * problem here and not every time the kernel is
-			 * entered.
-			 */
-			if (frame.tf_eflags & PSL_NT) {
-				frame.tf_eflags &= ~PSL_NT;
-				goto out;
-			}
-			break;
-
-		case T_TRCTRAP:	 /* trace trap */
-			if (frame.tf_eip == (int)IDTVEC(lcall_syscall)) {
-				/*
-				 * We've just entered system mode via the
-				 * syscall lcall.  Continue single stepping
-				 * silently until the syscall handler has
-				 * saved the flags.
-				 */
-				goto out;
-			}
-			if (frame.tf_eip == (int)IDTVEC(lcall_syscall) + 1) {
-				/*
-				 * The syscall handler has now saved the
-				 * flags.  Stop single stepping it.
-				 */
-				frame.tf_eflags &= ~PSL_T;
-				goto out;
-			}
-			/*
-			 * Ignore debug register trace traps due to
-			 * accesses in the user's address space, which
-			 * can happen under several conditions such as
-			 * if a user sets a watchpoint on a buffer and
-			 * then passes that buffer to a system call.
-			 * We still want to get TRCTRAPS for addresses
-			 * in kernel space because that is useful when
-			 * debugging the kernel.
-			 */
-			/* XXX Giant */
-			if (user_dbreg_trap() && !in_vm86call) {
-				/*
-				 * Reset breakpoint bits because the
-				 * processor doesn't
-				 */
-				load_dr6(rdr6() & 0xfffffff0);
-				goto out;
-			}
-			/*
-			 * Fall through (TRCTRAP kernel mode, kernel address)
-			 */
-		case T_BPTFLT:
-			/*
-			 * If DDB is enabled, let it handle the debugger trap.
-			 * Otherwise, debugger traps "can't happen".
-			 */
-#ifdef DDB
-			/* XXX Giant */
-			if (kdb_trap (type, 0, &frame))
-				goto out;
-#endif
-			break;
-
-#ifdef DEV_ISA
-		case T_NMI:
-#ifdef POWERFAIL_NMI
-			mtx_lock(&Giant);
-			if (time_second - lastalert > 10) {
-				log(LOG_WARNING, "NMI: power fail\n");
-				sysbeep(TIMER_FREQ/880, hz);
-				lastalert = time_second;
-			}
-			mtx_unlock(&Giant);
-			goto out;
-#else /* !POWERFAIL_NMI */
-			/* XXX Giant */
-			/* machine/parity/power fail/"kitchen sink" faults */
-			if (isa_nmi(code) == 0) {
-#ifdef DDB
-				/*
-				 * NMI can be hooked up to a pushbutton
-				 * for debugging.
-				 */
-				if (ddb_on_nmi) {
-					printf ("NMI ... going to debugger\n");
-					kdb_trap (type, 0, &frame);
-				}
-#endif /* DDB */
-				goto out;
-			} else if (panic_on_nmi == 0)
-				goto out;
-			/* FALL THROUGH */
-#endif /* POWERFAIL_NMI */
-#endif /* DEV_ISA */
-		}
-
-		trap_fatal(&frame, eva);
-		goto out;
-	}
-
-	mtx_lock(&Giant);
-	/* Translate fault for emulators (e.g. Linux) */
-	if (*p->p_sysent->sv_transtrap)
-		i = (*p->p_sysent->sv_transtrap)(i, type);
-
-	trapsignal(p, i, ucode);
-
-#ifdef DEBUG
-	if (type <= MAX_TRAP_MSG) {
-		uprintf("fatal process exception: %s",
-			trap_msg[type]);
-		if ((type == T_PAGEFLT) || (type == T_PROTFLT))
-			uprintf(", fault VA = 0x%lx", (u_long)eva);
-		uprintf("\n");
-	}
-#endif
-	mtx_unlock(&Giant);
-
-user:
-	userret(p, &frame, sticks);
-	if (mtx_owned(&Giant))
-		mtx_unlock(&Giant);
-out:
-	return;
-}
-
-#ifdef notyet
-/*
- * This version doesn't allow a page fault to user space while
- * in the kernel. The rest of the kernel needs to be made "safe"
- * before this can be used. I think the only things remaining
- * to be made safe are the iBCS2 code and the process tracing/
- * debugging code.
+ * Process an asynchronous software trap.
+ * This is relatively easy.
  */
-static int
-trap_pfault(frame, usermode, eva)
-	struct trapframe *frame;
-	int usermode;
-	vm_offset_t eva;
-{
-	vm_offset_t va;
-	struct vmspace *vm = NULL;
-	vm_map_t map = 0;
-	int rv = 0;
-	vm_prot_t ftype;
-	struct proc *p = curproc;
-
-	if (frame->tf_err & PGEX_W)
-		ftype = VM_PROT_WRITE;
-	else
-		ftype = VM_PROT_READ;
-
-	va = trunc_page(eva);
-	if (va < VM_MIN_KERNEL_ADDRESS) {
-		vm_offset_t v;
-		vm_page_t mpte;
-
-		if (p == NULL ||
-		    (!usermode && va < VM_MAXUSER_ADDRESS &&
-		     (p->p_intr_nesting_level != 0 ||
-		      PCPU_GET(curpcb) == NULL ||
-		      PCPU_GET(curpcb)->pcb_onfault == NULL))) {
-			trap_fatal(frame, eva);
-			return (-1);
-		}
-
-		/*
-		 * This is a fault on non-kernel virtual memory.
-		 * vm is initialized above to NULL. If curproc is NULL
-		 * or curproc->p_vmspace is NULL the fault is fatal.
-		 */
-		vm = p->p_vmspace;
-		if (vm == NULL)
-			goto nogo;
-
-		map = &vm->vm_map;
-
-		/*
-		 * Keep swapout from messing with us during this
-		 *	critical time.
-		 */
-		PROC_LOCK(p);
-		++p->p_lock;
-		PROC_UNLOCK(p);
-
-		/*
-		 * Grow the stack if necessary
-		 */
-		/* grow_stack returns false only if va falls into
-		 * a growable stack region and the stack growth
-		 * fails.  It returns true if va was not within
-		 * a growable stack region, or if the stack 
-		 * growth succeeded.
-		 */
-		if (!grow_stack (p, va))
-			rv = KERN_FAILURE;
-		else
-			/* Fault in the user page: */
-			rv = vm_fault(map, va, ftype,
-			      (ftype & VM_PROT_WRITE) ? VM_FAULT_DIRTY
-						      : VM_FAULT_NORMAL);
-
-		PROC_LOCK(p);
-		--p->p_lock;
-		PROC_UNLOCK(p);
-	} else {
-		/*
-		 * Don't allow user-mode faults in kernel address space.
-		 */
-		if (usermode)
-			goto nogo;
-
-		/*
-		 * Since we know that kernel virtual address addresses
-		 * always have pte pages mapped, we just have to fault
-		 * the page.
-		 */
-		rv = vm_fault(kernel_map, va, ftype, VM_FAULT_NORMAL);
-	}
-
-	if (rv == KERN_SUCCESS)
-		return (0);
-nogo:
-	if (!usermode) {
-		if (p->p_intr_nesting_level == 0 &&
-		    PCPU_GET(curpcb) != NULL &&
-		    PCPU_GET(curpcb)->pcb_onfault != NULL) {
-			frame->tf_eip = (int)PCPU_GET(curpcb)->pcb_onfault;
-			return (0);
-		}
-		trap_fatal(frame, eva);
-		return (-1);
-	}
-
-	/* kludge to pass faulting virtual address to sendsig */
-	frame->tf_err = eva;
-
-	return((rv == KERN_PROTECTION_FAILURE) ? SIGBUS : SIGSEGV);
-}
-#endif
-
-int
-trap_pfault(frame, usermode, eva)
-	struct trapframe *frame;
-	int usermode;
-	vm_offset_t eva;
-{
-	vm_offset_t va;
-	struct vmspace *vm = NULL;
-	vm_map_t map = 0;
-	int rv = 0;
-	vm_prot_t ftype;
-	struct proc *p = curproc;
-
-	va = trunc_page(eva);
-	if (va >= KERNBASE) {
-		/*
-		 * Don't allow user-mode faults in kernel address space.
-		 * An exception:  if the faulting address is the invalid
-		 * instruction entry in the IDT, then the Intel Pentium
-		 * F00F bug workaround was triggered, and we need to
-		 * treat it is as an illegal instruction, and not a page
-		 * fault.
-		 */
-#if defined(I586_CPU) && !defined(NO_F00F_HACK)
-		if ((eva == (unsigned int)&idt[6]) && has_f00f_bug)
-			return -2;
-#endif
-		if (usermode)
-			goto nogo;
-
-		map = kernel_map;
-	} else {
-		/*
-		 * This is a fault on non-kernel virtual memory.
-		 * vm is initialized above to NULL. If curproc is NULL
-		 * or curproc->p_vmspace is NULL the fault is fatal.
-		 */
-		if (p != NULL)
-			vm = p->p_vmspace;
-
-		if (vm == NULL)
-			goto nogo;
-
-		map = &vm->vm_map;
-	}
-
-	if (frame->tf_err & PGEX_W)
-		ftype = VM_PROT_WRITE;
-	else
-		ftype = VM_PROT_READ;
-
-	if (map != kernel_map) {
-		/*
-		 * Keep swapout from messing with us during this
-		 *	critical time.
-		 */
-		PROC_LOCK(p);
-		++p->p_lock;
-		PROC_UNLOCK(p);
-
-		/*
-		 * Grow the stack if necessary
-		 */
-		/* grow_stack returns false only if va falls into
-		 * a growable stack region and the stack growth
-		 * fails.  It returns true if va was not within
-		 * a growable stack region, or if the stack 
-		 * growth succeeded.
-		 */
-		if (!grow_stack (p, va))
-			rv = KERN_FAILURE;
-		else
-			/* Fault in the user page: */
-			rv = vm_fault(map, va, ftype,
-			      (ftype & VM_PROT_WRITE) ? VM_FAULT_DIRTY
-						      : VM_FAULT_NORMAL);
-
-		PROC_LOCK(p);
-		--p->p_lock;
-		PROC_UNLOCK(p);
-	} else {
-		/*
-		 * Don't have to worry about process locking or stacks in the
-		 * kernel.
-		 */
-		rv = vm_fault(map, va, ftype, VM_FAULT_NORMAL);
-	}
-
-	if (rv == KERN_SUCCESS)
-		return (0);
-nogo:
-	if (!usermode) {
-		if (p->p_intr_nesting_level == 0 &&
-		    PCPU_GET(curpcb) != NULL &&
-		    PCPU_GET(curpcb)->pcb_onfault != NULL) {
-			frame->tf_eip = (int)PCPU_GET(curpcb)->pcb_onfault;
-			return (0);
-		}
-		trap_fatal(frame, eva);
-		return (-1);
-	}
-
-	/* kludge to pass faulting virtual address to sendsig */
-	frame->tf_err = eva;
-
-	return((rv == KERN_PROTECTION_FAILURE) ? SIGBUS : SIGSEGV);
-}
-
-static void
-trap_fatal(frame, eva)
-	struct trapframe *frame;
-	vm_offset_t eva;
-{
-	int code, type, ss, esp;
-	struct soft_segment_descriptor softseg;
-
-	code = frame->tf_err;
-	type = frame->tf_trapno;
-	sdtossd(&gdt[IDXSEL(frame->tf_cs & 0xffff)].sd, &softseg);
-
-	if (type <= MAX_TRAP_MSG)
-		printf("\n\nFatal trap %d: %s while in %s mode\n",
-			type, trap_msg[type],
-        		frame->tf_eflags & PSL_VM ? "vm86" :
-			ISPL(frame->tf_cs) == SEL_UPL ? "user" : "kernel");
-#ifdef SMP
-	/* two separate prints in case of a trap on an unmapped page */
-	printf("cpuid = %d; ", PCPU_GET(cpuid));
-	printf("lapic.id = %08x\n", lapic.id);
-#endif
-	if (type == T_PAGEFLT) {
-		printf("fault virtual address	= 0x%x\n", eva);
-		printf("fault code		= %s %s, %s\n",
-			code & PGEX_U ? "user" : "supervisor",
-			code & PGEX_W ? "write" : "read",
-			code & PGEX_P ? "protection violation" : "page not present");
-	}
-	printf("instruction pointer	= 0x%x:0x%x\n",
-	       frame->tf_cs & 0xffff, frame->tf_eip);
-        if ((ISPL(frame->tf_cs) == SEL_UPL) || (frame->tf_eflags & PSL_VM)) {
-		ss = frame->tf_ss & 0xffff;
-		esp = frame->tf_esp;
-	} else {
-		ss = GSEL(GDATA_SEL, SEL_KPL);
-		esp = (int)&frame->tf_esp;
-	}
-	printf("stack pointer	        = 0x%x:0x%x\n", ss, esp);
-	printf("frame pointer	        = 0x%x:0x%x\n", ss, frame->tf_ebp);
-	printf("code segment		= base 0x%x, limit 0x%x, type 0x%x\n",
-	       softseg.ssd_base, softseg.ssd_limit, softseg.ssd_type);
-	printf("			= DPL %d, pres %d, def32 %d, gran %d\n",
-	       softseg.ssd_dpl, softseg.ssd_p, softseg.ssd_def32,
-	       softseg.ssd_gran);
-	printf("processor eflags	= ");
-	if (frame->tf_eflags & PSL_T)
-		printf("trace trap, ");
-	if (frame->tf_eflags & PSL_I)
-		printf("interrupt enabled, ");
-	if (frame->tf_eflags & PSL_NT)
-		printf("nested task, ");
-	if (frame->tf_eflags & PSL_RF)
-		printf("resume, ");
-	if (frame->tf_eflags & PSL_VM)
-		printf("vm86, ");
-	printf("IOPL = %d\n", (frame->tf_eflags & PSL_IOPL) >> 12);
-	printf("current process		= ");
-	if (curproc) {
-		printf("%lu (%s)\n",
-		    (u_long)curproc->p_pid, curproc->p_comm ?
-		    curproc->p_comm : "");
-	} else {
-		printf("Idle\n");
-	}
-
-#ifdef KDB
-	if (kdb_trap(&psl))
-		return;
-#endif
-#ifdef DDB
-	if ((debugger_on_panic || db_active) && kdb_trap(type, 0, frame))
-		return;
-#endif
-	printf("trap number		= %d\n", type);
-	if (type <= MAX_TRAP_MSG)
-		panic(trap_msg[type]);
-	else
-		panic("unknown/reserved trap");
-}
-
-/*
- * Double fault handler. Called when a fault occurs while writing
- * a frame for a trap/exception onto the stack. This usually occurs
- * when the stack overflows (such is the case with infinite recursion,
- * for example).
- *
- * XXX Note that the current PTD gets replaced by IdlePTD when the
- * task switch occurs. This means that the stack that was active at
- * the time of the double fault is not available at <kstack> unless
- * the machine was idle when the double fault occurred. The downside
- * of this is that "trace <ebp>" in ddb won't work.
- */
-void
-dblfault_handler()
-{
-	printf("\nFatal double fault:\n");
-	printf("eip = 0x%x\n", PCPU_GET(common_tss.tss_eip));
-	printf("esp = 0x%x\n", PCPU_GET(common_tss.tss_esp));
-	printf("ebp = 0x%x\n", PCPU_GET(common_tss.tss_ebp));
-#ifdef SMP
-	/* two separate prints in case of a trap on an unmapped page */
-	printf("cpuid = %d; ", PCPU_GET(cpuid));
-	printf("lapic.id = %08x\n", lapic.id);
-#endif
-	panic("double fault");
-}
-
-/*
- * Compensate for 386 brain damage (missing URKR).
- * This is a little simpler than the pagefault handler in trap() because
- * it the page tables have already been faulted in and high addresses
- * are thrown out early for other reasons.
- */
-int trapwrite(addr)
-	unsigned addr;
-{
-	struct proc *p;
-	vm_offset_t va;
-	struct vmspace *vm;
-	int rv;
-
-	va = trunc_page((vm_offset_t)addr);
-	/*
-	 * XXX - MAX is END.  Changed > to >= for temp. fix.
-	 */
-	if (va >= VM_MAXUSER_ADDRESS)
-		return (1);
-
-	p = curproc;
-	vm = p->p_vmspace;
-
-	PROC_LOCK(p);
-	++p->p_lock;
-	PROC_UNLOCK(p);
-
-	if (!grow_stack (p, va))
-		rv = KERN_FAILURE;
-	else
-		/*
-		 * fault the data page
-		 */
-		rv = vm_fault(&vm->vm_map, va, VM_PROT_WRITE, VM_FAULT_DIRTY);
-
-	PROC_LOCK(p);
-	--p->p_lock;
-	PROC_UNLOCK(p);
-
-	if (rv != KERN_SUCCESS)
-		return 1;
-
-	return (0);
-}
-
-/*
- *	syscall -	MP aware system call request C handler
- *
- *	A system call is essentially treated as a trap except that the
- *	MP lock is not held on entry or return.  We are responsible for
- *	obtaining the MP lock if necessary and for handling ASTs
- *	(e.g. a task switch) prior to return.
- *
- *	In general, only simple access and manipulation of curproc and
- *	the current stack is allowed without having to hold MP lock.
- */
-void
-syscall(frame)
-	struct trapframe frame;
-{
-	caddr_t params;
-	int i;
-	struct sysent *callp;
-	struct proc *p = curproc;
-	u_quad_t sticks;
-	int error;
-	int narg;
-	int args[8];
-	u_int code;
-
-	atomic_add_int(&cnt.v_syscall, 1);
-
-#ifdef DIAGNOSTIC
-	if (ISPL(frame.tf_cs) != SEL_UPL) {
-		mtx_lock(&Giant);
-		panic("syscall");
-		/* NOT REACHED */
-	}
-#endif
-
-	mtx_lock_spin(&sched_lock);
-	sticks = p->p_sticks;
-	mtx_unlock_spin(&sched_lock);
-
-	p->p_frame = &frame;
-	params = (caddr_t)frame.tf_esp + sizeof(int);
-	code = frame.tf_eax;
-
-	if (p->p_sysent->sv_prepsyscall) {
-		/*
-		 * The prep code is not MP aware.
-		 */
-		mtx_lock(&Giant);
-		(*p->p_sysent->sv_prepsyscall)(&frame, args, &code, &params);
-		mtx_unlock(&Giant);
-	} else {
-		/*
-		 * Need to check if this is a 32 bit or 64 bit syscall.
-		 * fuword is MP aware.
-		 */
-		if (code == SYS_syscall) {
-			/*
-			 * Code is first argument, followed by actual args.
-			 */
-			code = fuword(params);
-			params += sizeof(int);
-		} else if (code == SYS___syscall) {
-			/*
-			 * Like syscall, but code is a quad, so as to maintain
-			 * quad alignment for the rest of the arguments.
-			 */
-			code = fuword(params);
-			params += sizeof(quad_t);
-		}
-	}
-
- 	if (p->p_sysent->sv_mask)
- 		code &= p->p_sysent->sv_mask;
-
- 	if (code >= p->p_sysent->sv_size)
- 		callp = &p->p_sysent->sv_table[0];
-  	else
- 		callp = &p->p_sysent->sv_table[code];
-
-	narg = callp->sy_narg & SYF_ARGMASK;
-
-	/*
-	 * copyin is MP aware, but the tracing code is not
-	 */
-	if (params && (i = narg * sizeof(int)) &&
-	    (error = copyin(params, (caddr_t)args, (u_int)i))) {
-		mtx_lock(&Giant);
-#ifdef KTRACE
-		if (KTRPOINT(p, KTR_SYSCALL))
-			ktrsyscall(p->p_tracep, code, narg, args);
-#endif
-		goto bad;
-	}
-
-	/*
-	 * Try to run the syscall without the MP lock if the syscall
-	 * is MP safe.
-	 */
-	if ((callp->sy_narg & SYF_MPSAFE) == 0) {
-		mtx_lock(&Giant);
-	}
-
-#ifdef KTRACE
-	/*
-	 * We have to obtain the MP lock no matter what if 
-	 * we are ktracing
-	 */
-	if (KTRPOINT(p, KTR_SYSCALL)) {
-		if (!mtx_owned(&Giant))
-			mtx_lock(&Giant);
-		ktrsyscall(p->p_tracep, code, narg, args);
-	}
-#endif
-	p->p_retval[0] = 0;
-	p->p_retval[1] = frame.tf_edx;
-
-	STOPEVENT(p, S_SCE, narg);	/* MP aware */
-
-	error = (*callp->sy_call)(p, args);
-
-	/*
-	 * MP SAFE (we may or may not have the MP lock at this point)
-	 */
-	switch (error) {
-	case 0:
-		frame.tf_eax = p->p_retval[0];
-		frame.tf_edx = p->p_retval[1];
-		frame.tf_eflags &= ~PSL_C;
-		break;
-
-	case ERESTART:
-		/*
-		 * Reconstruct pc, assuming lcall $X,y is 7 bytes,
-		 * int 0x80 is 2 bytes. We saved this in tf_err.
-		 */
-		frame.tf_eip -= frame.tf_err;
-		break;
-
-	case EJUSTRETURN:
-		break;
-
-	default:
-bad:
- 		if (p->p_sysent->sv_errsize) {
- 			if (error >= p->p_sysent->sv_errsize)
-  				error = -1;	/* XXX */
-   			else
-  				error = p->p_sysent->sv_errtbl[error];
-		}
-		frame.tf_eax = error;
-		frame.tf_eflags |= PSL_C;
-		break;
-	}
-
-	/*
-	 * Traced syscall.  trapsignal() is not MP aware.
-	 */
-	if ((frame.tf_eflags & PSL_T) && !(frame.tf_eflags & PSL_VM)) {
-		if (!mtx_owned(&Giant))
-			mtx_lock(&Giant);
-		frame.tf_eflags &= ~PSL_T;
-		trapsignal(p, SIGTRAP, 0);
-	}
-
-	/*
-	 * Handle reschedule and other end-of-syscall issues
-	 */
-	userret(p, &frame, sticks);
-
-#ifdef KTRACE
-	if (KTRPOINT(p, KTR_SYSRET)) {
-		if (!mtx_owned(&Giant))
-			mtx_lock(&Giant);
-		ktrsysret(p->p_tracep, code, error, p->p_retval[0]);
-	}
-#endif
-
-	/*
-	 * Release Giant if we had to get it
-	 */
-	if (mtx_owned(&Giant))
-		mtx_unlock(&Giant);
-
-	/*
-	 * This works because errno is findable through the
-	 * register set.  If we ever support an emulation where this
-	 * is not the case, this code will need to be revisited.
-	 */
-	STOPEVENT(p, S_SCX, code);
-
-#ifdef WITNESS
-	if (witness_list(p)) {
-		panic("system call %s returning with mutex(s) held\n",
-		    syscallnames[code]);
-	}
-#endif
-	mtx_assert(&sched_lock, MA_NOTOWNED);
-	mtx_assert(&Giant, MA_NOTOWNED);
-}
-
 void
 ast(framep)
 	struct trapframe *framep;