freebsd-nq/sys/powerpc/aim/trap.c
Mark Johnston cafe874475 Restore the trap type argument to the DTrace trap hook, removed in r268600.
It's redundant at the moment since it can be obtained from the trapframe
on the architectures where DTrace is supported, but this won't be the case
with ARM.
2014-12-23 15:38:19 +00:00

743 lines
17 KiB
C

/*-
* Copyright (C) 1995, 1996 Wolfgang Solfrank.
* Copyright (C) 1995, 1996 TooLs GmbH.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by TooLs GmbH.
* 4. The name of TooLs GmbH may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $NetBSD: trap.c,v 1.58 2002/03/04 04:07:35 dbj Exp $
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/kdb.h>
#include <sys/proc.h>
#include <sys/ktr.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/pioctl.h>
#include <sys/ptrace.h>
#include <sys/reboot.h>
#include <sys/syscall.h>
#include <sys/sysent.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/uio.h>
#include <sys/signalvar.h>
#include <sys/vmmeter.h>
#include <security/audit/audit.h>
#include <vm/vm.h>
#include <vm/pmap.h>
#include <vm/vm_extern.h>
#include <vm/vm_param.h>
#include <vm/vm_kern.h>
#include <vm/vm_map.h>
#include <vm/vm_page.h>
#include <machine/_inttypes.h>
#include <machine/altivec.h>
#include <machine/cpu.h>
#include <machine/db_machdep.h>
#include <machine/fpu.h>
#include <machine/frame.h>
#include <machine/pcb.h>
#include <machine/pmap.h>
#include <machine/psl.h>
#include <machine/trap.h>
#include <machine/spr.h>
#include <machine/sr.h>
static void trap_fatal(struct trapframe *frame);
static void printtrap(u_int vector, struct trapframe *frame, int isfatal,
int user);
static int trap_pfault(struct trapframe *frame, int user);
static int fix_unaligned(struct thread *td, struct trapframe *frame);
static int handle_onfault(struct trapframe *frame);
static void syscall(struct trapframe *frame);
#ifdef __powerpc64__
void handle_kernel_slb_spill(int, register_t, register_t);
static int handle_user_slb_spill(pmap_t pm, vm_offset_t addr);
extern int n_slbs;
#endif
struct powerpc_exception {
u_int vector;
char *name;
};
#ifdef KDTRACE_HOOKS
#include <sys/dtrace_bsd.h>
int (*dtrace_invop_jump_addr)(struct trapframe *);
#endif
static struct powerpc_exception powerpc_exceptions[] = {
{ 0x0100, "system reset" },
{ 0x0200, "machine check" },
{ 0x0300, "data storage interrupt" },
{ 0x0380, "data segment exception" },
{ 0x0400, "instruction storage interrupt" },
{ 0x0480, "instruction segment exception" },
{ 0x0500, "external interrupt" },
{ 0x0600, "alignment" },
{ 0x0700, "program" },
{ 0x0800, "floating-point unavailable" },
{ 0x0900, "decrementer" },
{ 0x0c00, "system call" },
{ 0x0d00, "trace" },
{ 0x0e00, "floating-point assist" },
{ 0x0f00, "performance monitoring" },
{ 0x0f20, "altivec unavailable" },
{ 0x1000, "instruction tlb miss" },
{ 0x1100, "data load tlb miss" },
{ 0x1200, "data store tlb miss" },
{ 0x1300, "instruction breakpoint" },
{ 0x1400, "system management" },
{ 0x1600, "altivec assist" },
{ 0x1700, "thermal management" },
{ 0x2000, "run mode/trace" },
{ 0x3000, NULL }
};
static const char *
trapname(u_int vector)
{
struct powerpc_exception *pe;
for (pe = powerpc_exceptions; pe->vector != 0x3000; pe++) {
if (pe->vector == vector)
return (pe->name);
}
return ("unknown");
}
void
trap(struct trapframe *frame)
{
struct thread *td;
struct proc *p;
#ifdef KDTRACE_HOOKS
uint32_t inst;
#endif
int sig, type, user;
u_int ucode;
ksiginfo_t ksi;
PCPU_INC(cnt.v_trap);
td = curthread;
p = td->td_proc;
type = ucode = frame->exc;
sig = 0;
user = frame->srr1 & PSL_PR;
CTR3(KTR_TRAP, "trap: %s type=%s (%s)", td->td_name,
trapname(type), user ? "user" : "kernel");
#ifdef KDTRACE_HOOKS
/*
* A trap can occur while DTrace executes a probe. Before
* executing the probe, DTrace blocks re-scheduling and sets
* a flag in its per-cpu flags to indicate that it doesn't
* want to fault. On returning from the probe, the no-fault
* flag is cleared and finally re-scheduling is enabled.
*
* If the DTrace kernel module has registered a trap handler,
* call it and if it returns non-zero, assume that it has
* handled the trap and modified the trap frame so that this
* function can return normally.
*/
if (dtrace_trap_func != NULL && (*dtrace_trap_func)(frame, type) != 0)
return;
#endif
if (user) {
td->td_pticks = 0;
td->td_frame = frame;
if (td->td_ucred != p->p_ucred)
cred_update_thread(td);
/* User Mode Traps */
switch (type) {
case EXC_RUNMODETRC:
case EXC_TRC:
frame->srr1 &= ~PSL_SE;
sig = SIGTRAP;
ucode = TRAP_TRACE;
break;
#ifdef __powerpc64__
case EXC_ISE:
case EXC_DSE:
if (handle_user_slb_spill(&p->p_vmspace->vm_pmap,
(type == EXC_ISE) ? frame->srr0 :
frame->cpu.aim.dar) != 0) {
sig = SIGSEGV;
ucode = SEGV_MAPERR;
}
break;
#endif
case EXC_DSI:
case EXC_ISI:
sig = trap_pfault(frame, 1);
if (sig == SIGSEGV)
ucode = SEGV_MAPERR;
break;
case EXC_SC:
syscall(frame);
break;
case EXC_FPU:
KASSERT((td->td_pcb->pcb_flags & PCB_FPU) != PCB_FPU,
("FPU already enabled for thread"));
enable_fpu(td);
break;
case EXC_VEC:
KASSERT((td->td_pcb->pcb_flags & PCB_VEC) != PCB_VEC,
("Altivec already enabled for thread"));
enable_vec(td);
break;
case EXC_VECAST_G4:
case EXC_VECAST_G5:
/*
* We get a VPU assist exception for IEEE mode
* vector operations on denormalized floats.
* Emulating this is a giant pain, so for now,
* just switch off IEEE mode and treat them as
* zero.
*/
save_vec(td);
td->td_pcb->pcb_vec.vscr |= ALTIVEC_VSCR_NJ;
enable_vec(td);
break;
case EXC_ALI:
if (fix_unaligned(td, frame) != 0) {
sig = SIGBUS;
ucode = BUS_ADRALN;
}
else
frame->srr0 += 4;
break;
case EXC_PGM:
/* Identify the trap reason */
if (frame->srr1 & EXC_PGM_TRAP) {
#ifdef KDTRACE_HOOKS
inst = fuword32((const void *)frame->srr0);
if (inst == 0x0FFFDDDD &&
dtrace_pid_probe_ptr != NULL) {
struct reg regs;
fill_regs(td, &regs);
(*dtrace_pid_probe_ptr)(&regs);
break;
}
#endif
sig = SIGTRAP;
ucode = TRAP_BRKPT;
} else {
sig = ppc_instr_emulate(frame, td->td_pcb);
if (sig == SIGILL) {
if (frame->srr1 & EXC_PGM_PRIV)
ucode = ILL_PRVOPC;
else if (frame->srr1 & EXC_PGM_ILLEGAL)
ucode = ILL_ILLOPC;
} else if (sig == SIGFPE)
ucode = FPE_FLTINV; /* Punt for now, invalid operation. */
}
break;
case EXC_MCHK:
/*
* Note that this may not be recoverable for the user
* process, depending on the type of machine check,
* but it at least prevents the kernel from dying.
*/
sig = SIGBUS;
ucode = BUS_OBJERR;
break;
default:
trap_fatal(frame);
}
} else {
/* Kernel Mode Traps */
KASSERT(cold || td->td_ucred != NULL,
("kernel trap doesn't have ucred"));
switch (type) {
#ifdef KDTRACE_HOOKS
case EXC_PGM:
if (frame->srr1 & EXC_PGM_TRAP) {
if (*(uint32_t *)frame->srr0 == EXC_DTRACE) {
if (dtrace_invop_jump_addr != NULL) {
dtrace_invop_jump_addr(frame);
return;
}
}
}
break;
#endif
#ifdef __powerpc64__
case EXC_DSE:
if ((frame->cpu.aim.dar & SEGMENT_MASK) == USER_ADDR) {
__asm __volatile ("slbmte %0, %1" ::
"r"(td->td_pcb->pcb_cpu.aim.usr_vsid),
"r"(USER_SLB_SLBE));
return;
}
break;
#endif
case EXC_DSI:
if (trap_pfault(frame, 0) == 0)
return;
break;
case EXC_MCHK:
if (handle_onfault(frame))
return;
break;
default:
break;
}
trap_fatal(frame);
}
if (sig != 0) {
if (p->p_sysent->sv_transtrap != NULL)
sig = (p->p_sysent->sv_transtrap)(sig, type);
ksiginfo_init_trap(&ksi);
ksi.ksi_signo = sig;
ksi.ksi_code = (int) ucode; /* XXX, not POSIX */
/* ksi.ksi_addr = ? */
ksi.ksi_trapno = type;
trapsignal(td, &ksi);
}
userret(td, frame);
}
static void
trap_fatal(struct trapframe *frame)
{
printtrap(frame->exc, frame, 1, (frame->srr1 & PSL_PR));
#ifdef KDB
if ((debugger_on_panic || kdb_active) &&
kdb_trap(frame->exc, 0, frame))
return;
#endif
panic("%s trap", trapname(frame->exc));
}
static void
printtrap(u_int vector, struct trapframe *frame, int isfatal, int user)
{
printf("\n");
printf("%s %s trap:\n", isfatal ? "fatal" : "handled",
user ? "user" : "kernel");
printf("\n");
printf(" exception = 0x%x (%s)\n", vector, trapname(vector));
switch (vector) {
case EXC_DSE:
case EXC_DSI:
printf(" virtual address = 0x%" PRIxPTR "\n",
frame->cpu.aim.dar);
printf(" dsisr = 0x%" PRIxPTR "\n",
frame->cpu.aim.dsisr);
break;
case EXC_ISE:
case EXC_ISI:
printf(" virtual address = 0x%" PRIxPTR "\n", frame->srr0);
break;
}
printf(" srr0 = 0x%" PRIxPTR "\n", frame->srr0);
printf(" srr1 = 0x%" PRIxPTR "\n", frame->srr1);
printf(" lr = 0x%" PRIxPTR "\n", frame->lr);
printf(" curthread = %p\n", curthread);
if (curthread != NULL)
printf(" pid = %d, comm = %s\n",
curthread->td_proc->p_pid, curthread->td_name);
printf("\n");
}
/*
* Handles a fatal fault when we have onfault state to recover. Returns
* non-zero if there was onfault recovery state available.
*/
static int
handle_onfault(struct trapframe *frame)
{
struct thread *td;
faultbuf *fb;
td = curthread;
fb = td->td_pcb->pcb_onfault;
if (fb != NULL) {
frame->srr0 = (*fb)[0];
frame->fixreg[1] = (*fb)[1];
frame->fixreg[2] = (*fb)[2];
frame->fixreg[3] = 1;
frame->cr = (*fb)[3];
bcopy(&(*fb)[4], &frame->fixreg[13],
19 * sizeof(register_t));
return (1);
}
return (0);
}
int
cpu_fetch_syscall_args(struct thread *td, struct syscall_args *sa)
{
struct proc *p;
struct trapframe *frame;
caddr_t params;
size_t argsz;
int error, n, i;
p = td->td_proc;
frame = td->td_frame;
sa->code = frame->fixreg[0];
params = (caddr_t)(frame->fixreg + FIRSTARG);
n = NARGREG;
if (sa->code == SYS_syscall) {
/*
* code is first argument,
* followed by actual args.
*/
sa->code = *(register_t *) params;
params += sizeof(register_t);
n -= 1;
} else if (sa->code == SYS___syscall) {
/*
* Like syscall, but code is a quad,
* so as to maintain quad alignment
* for the rest of the args.
*/
if (SV_PROC_FLAG(p, SV_ILP32)) {
params += sizeof(register_t);
sa->code = *(register_t *) params;
params += sizeof(register_t);
n -= 2;
} else {
sa->code = *(register_t *) params;
params += sizeof(register_t);
n -= 1;
}
}
if (p->p_sysent->sv_mask)
sa->code &= p->p_sysent->sv_mask;
if (sa->code >= p->p_sysent->sv_size)
sa->callp = &p->p_sysent->sv_table[0];
else
sa->callp = &p->p_sysent->sv_table[sa->code];
sa->narg = sa->callp->sy_narg;
if (SV_PROC_FLAG(p, SV_ILP32)) {
argsz = sizeof(uint32_t);
for (i = 0; i < n; i++)
sa->args[i] = ((u_register_t *)(params))[i] &
0xffffffff;
} else {
argsz = sizeof(uint64_t);
for (i = 0; i < n; i++)
sa->args[i] = ((u_register_t *)(params))[i];
}
if (sa->narg > n)
error = copyin(MOREARGS(frame->fixreg[1]), sa->args + n,
(sa->narg - n) * argsz);
else
error = 0;
#ifdef __powerpc64__
if (SV_PROC_FLAG(p, SV_ILP32) && sa->narg > n) {
/* Expand the size of arguments copied from the stack */
for (i = sa->narg; i >= n; i--)
sa->args[i] = ((uint32_t *)(&sa->args[n]))[i-n];
}
#endif
if (error == 0) {
td->td_retval[0] = 0;
td->td_retval[1] = frame->fixreg[FIRSTARG + 1];
}
return (error);
}
#include "../../kern/subr_syscall.c"
void
syscall(struct trapframe *frame)
{
struct thread *td;
struct syscall_args sa;
int error;
td = curthread;
td->td_frame = frame;
#ifdef __powerpc64__
/*
* Speculatively restore last user SLB segment, which we know is
* invalid already, since we are likely to do copyin()/copyout().
*/
__asm __volatile ("slbmte %0, %1; isync" ::
"r"(td->td_pcb->pcb_cpu.aim.usr_vsid), "r"(USER_SLB_SLBE));
#endif
error = syscallenter(td, &sa);
syscallret(td, error, &sa);
}
#ifdef __powerpc64__
/* Handle kernel SLB faults -- runs in real mode, all seat belts off */
void
handle_kernel_slb_spill(int type, register_t dar, register_t srr0)
{
struct slb *slbcache;
uint64_t slbe, slbv;
uint64_t esid, addr;
int i;
addr = (type == EXC_ISE) ? srr0 : dar;
slbcache = PCPU_GET(slb);
esid = (uintptr_t)addr >> ADDR_SR_SHFT;
slbe = (esid << SLBE_ESID_SHIFT) | SLBE_VALID;
/* See if the hardware flushed this somehow (can happen in LPARs) */
for (i = 0; i < n_slbs; i++)
if (slbcache[i].slbe == (slbe | (uint64_t)i))
return;
/* Not in the map, needs to actually be added */
slbv = kernel_va_to_slbv(addr);
if (slbcache[USER_SLB_SLOT].slbe == 0) {
for (i = 0; i < n_slbs; i++) {
if (i == USER_SLB_SLOT)
continue;
if (!(slbcache[i].slbe & SLBE_VALID))
goto fillkernslb;
}
if (i == n_slbs)
slbcache[USER_SLB_SLOT].slbe = 1;
}
/* Sacrifice a random SLB entry that is not the user entry */
i = mftb() % n_slbs;
if (i == USER_SLB_SLOT)
i = (i+1) % n_slbs;
fillkernslb:
/* Write new entry */
slbcache[i].slbv = slbv;
slbcache[i].slbe = slbe | (uint64_t)i;
/* Trap handler will restore from cache on exit */
}
static int
handle_user_slb_spill(pmap_t pm, vm_offset_t addr)
{
struct slb *user_entry;
uint64_t esid;
int i;
esid = (uintptr_t)addr >> ADDR_SR_SHFT;
PMAP_LOCK(pm);
user_entry = user_va_to_slb_entry(pm, addr);
if (user_entry == NULL) {
/* allocate_vsid auto-spills it */
(void)allocate_user_vsid(pm, esid, 0);
} else {
/*
* Check that another CPU has not already mapped this.
* XXX: Per-thread SLB caches would be better.
*/
for (i = 0; i < pm->pm_slb_len; i++)
if (pm->pm_slb[i] == user_entry)
break;
if (i == pm->pm_slb_len)
slb_insert_user(pm, user_entry);
}
PMAP_UNLOCK(pm);
return (0);
}
#endif
static int
trap_pfault(struct trapframe *frame, int user)
{
vm_offset_t eva, va;
struct thread *td;
struct proc *p;
vm_map_t map;
vm_prot_t ftype;
int rv;
register_t user_sr;
td = curthread;
p = td->td_proc;
if (frame->exc == EXC_ISI) {
eva = frame->srr0;
ftype = VM_PROT_EXECUTE;
if (frame->srr1 & SRR1_ISI_PFAULT)
ftype |= VM_PROT_READ;
} else {
eva = frame->cpu.aim.dar;
if (frame->cpu.aim.dsisr & DSISR_STORE)
ftype = VM_PROT_WRITE;
else
ftype = VM_PROT_READ;
}
if (user) {
map = &p->p_vmspace->vm_map;
} else {
if ((eva >> ADDR_SR_SHFT) == (USER_ADDR >> ADDR_SR_SHFT)) {
if (p->p_vmspace == NULL)
return (SIGSEGV);
map = &p->p_vmspace->vm_map;
user_sr = td->td_pcb->pcb_cpu.aim.usr_segm;
eva &= ADDR_PIDX | ADDR_POFF;
eva |= user_sr << ADDR_SR_SHFT;
} else {
map = kernel_map;
}
}
va = trunc_page(eva);
if (map != kernel_map) {
/*
* Keep swapout from messing with us during this
* critical time.
*/
PROC_LOCK(p);
++p->p_lock;
PROC_UNLOCK(p);
/* Fault in the user page: */
rv = vm_fault(map, va, ftype, VM_FAULT_NORMAL);
PROC_LOCK(p);
--p->p_lock;
PROC_UNLOCK(p);
/*
* XXXDTRACE: add dtrace_doubletrap_func here?
*/
} 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);
if (!user && handle_onfault(frame))
return (0);
return (SIGSEGV);
}
/*
* For now, this only deals with the particular unaligned access case
* that gcc tends to generate. Eventually it should handle all of the
* possibilities that can happen on a 32-bit PowerPC in big-endian mode.
*/
static int
fix_unaligned(struct thread *td, struct trapframe *frame)
{
struct thread *fputhread;
int indicator, reg;
double *fpr;
indicator = EXC_ALI_OPCODE_INDICATOR(frame->cpu.aim.dsisr);
switch (indicator) {
case EXC_ALI_LFD:
case EXC_ALI_STFD:
reg = EXC_ALI_RST(frame->cpu.aim.dsisr);
fpr = &td->td_pcb->pcb_fpu.fpr[reg];
fputhread = PCPU_GET(fputhread);
/* Juggle the FPU to ensure that we've initialized
* the FPRs, and that their current state is in
* the PCB.
*/
if (fputhread != td) {
if (fputhread)
save_fpu(fputhread);
enable_fpu(td);
}
save_fpu(td);
if (indicator == EXC_ALI_LFD) {
if (copyin((void *)frame->cpu.aim.dar, fpr,
sizeof(double)) != 0)
return -1;
enable_fpu(td);
} else {
if (copyout(fpr, (void *)frame->cpu.aim.dar,
sizeof(double)) != 0)
return -1;
}
return 0;
break;
}
return -1;
}