void
m88110_trap(unsigned type, struct trapframe *frame)
{
struct proc *p;
u_quad_t sticks = 0;
struct vm_map *map;
vaddr_t va, pcb_onfault;
vm_prot_t ftype;
int fault_type;
u_long fault_code;
unsigned nss, fault_addr;
struct vmspace *vm;
union sigval sv;
int result;
#ifdef DDB
int s;
#endif
int sig = 0;
pt_entry_t *pte;
extern struct vm_map *kernel_map;
extern unsigned guarded_access_start;
extern unsigned guarded_access_end;
extern unsigned guarded_access_bad;
extern pt_entry_t *pmap_pte(pmap_t, vaddr_t);
uvmexp.traps++;
if ((p = curproc) == NULL)
p = &proc0;
if (USERMODE(frame->tf_epsr)) {
sticks = p->p_sticks;
type += T_USER;
p->p_md.md_tf = frame; /* for ptrace/signals */
}
fault_type = 0;
fault_code = 0;
fault_addr = frame->tf_exip & XIP_ADDR;
switch (type) {
default:
panictrap(frame->tf_vector, frame);
break;
/*NOTREACHED*/
case T_197_READ+T_USER:
case T_197_READ:
printf("DMMU read miss: Hardware Table Searches should be enabled!\n");
panictrap(frame->tf_vector, frame);
break;
/*NOTREACHED*/
case T_197_WRITE+T_USER:
case T_197_WRITE:
printf("DMMU write miss: Hardware Table Searches should be enabled!\n");
panictrap(frame->tf_vector, frame);
break;
/*NOTREACHED*/
case T_197_INST+T_USER:
case T_197_INST:
printf("IMMU miss: Hardware Table Searches should be enabled!\n");
panictrap(frame->tf_vector, frame);
break;
/*NOTREACHED*/
#ifdef DDB
case T_KDB_TRACE:
s = splhigh();
db_enable_interrupt();
ddb_break_trap(T_KDB_TRACE, (db_regs_t*)frame);
db_disable_interrupt();
splx(s);
return;
case T_KDB_BREAK:
s = splhigh();
db_enable_interrupt();
ddb_break_trap(T_KDB_BREAK, (db_regs_t*)frame);
db_disable_interrupt();
splx(s);
return;
case T_KDB_ENTRY:
s = splhigh();
db_enable_interrupt();
ddb_entry_trap(T_KDB_ENTRY, (db_regs_t*)frame);
db_disable_interrupt();
/* skip one instruction */
if (frame->tf_exip & 1)
frame->tf_exip = frame->tf_enip;
else
frame->tf_exip += 4;
splx(s);
return;
#if 0
case T_ILLFLT:
s = splhigh();
db_enable_interrupt();
ddb_error_trap(type == T_ILLFLT ? "unimplemented opcode" :
"error fault", (db_regs_t*)frame);
db_disable_interrupt();
splx(s);
return;
#endif /* 0 */
#endif /* DDB */
case T_ILLFLT:
printf("Unimplemented opcode!\n");
panictrap(frame->tf_vector, frame);
break;
case T_NON_MASK:
case T_NON_MASK+T_USER:
(*md.interrupt_func)(T_NON_MASK, frame);
return;
case T_INT:
case T_INT+T_USER:
(*md.interrupt_func)(T_INT, frame);
return;
case T_MISALGNFLT:
printf("kernel mode misaligned access exception @ 0x%08x\n",
frame->tf_exip);
panictrap(frame->tf_vector, frame);
break;
/*NOTREACHED*/
case T_INSTFLT:
/* kernel mode instruction access fault.
* Should never, never happen for a non-paged kernel.
*/
#ifdef TRAPDEBUG
printf("Kernel Instruction fault exip %x isr %x ilar %x\n",
frame->tf_exip, frame->tf_isr, frame->tf_ilar);
#endif
panictrap(frame->tf_vector, frame);
break;
/*NOTREACHED*/
case T_DATAFLT:
/* kernel mode data fault */
/* data fault on the user address? */
if ((frame->tf_dsr & CMMU_DSR_SU) == 0) {
type = T_DATAFLT + T_USER;
goto m88110_user_fault;
}
#ifdef TRAPDEBUG
printf("Kernel Data access fault exip %x dsr %x dlar %x\n",
frame->tf_exip, frame->tf_dsr, frame->tf_dlar);
#endif
fault_addr = frame->tf_dlar;
if (frame->tf_dsr & CMMU_DSR_RW) {
ftype = VM_PROT_READ;
fault_code = VM_PROT_READ;
} else {
ftype = VM_PROT_READ|VM_PROT_WRITE;
fault_code = VM_PROT_WRITE;
}
va = trunc_page((vaddr_t)fault_addr);
if (va == 0) {
panic("trap: bad kernel access at %x", fault_addr);
}
vm = p->p_vmspace;
map = kernel_map;
if (frame->tf_dsr & CMMU_DSR_BE) {
/*
* If it is a guarded access, bus error is OK.
*/
if ((frame->tf_exip & XIP_ADDR) >=
(unsigned)&guarded_access_start &&
(frame->tf_exip & XIP_ADDR) <=
(unsigned)&guarded_access_end) {
frame->tf_exip = (unsigned)&guarded_access_bad;
return;
}
}
if (frame->tf_dsr & (CMMU_DSR_SI | CMMU_DSR_PI)) {
frame->tf_dsr &= ~CMMU_DSR_WE; /* undefined */
/*
* On a segment or a page fault, call uvm_fault() to
* resolve the fault.
*/
if ((pcb_onfault = p->p_addr->u_pcb.pcb_onfault) != 0)
p->p_addr->u_pcb.pcb_onfault = 0;
result = uvm_fault(map, va, VM_FAULT_INVALID, ftype);
p->p_addr->u_pcb.pcb_onfault = pcb_onfault;
if (result == 0)
return;
}
if (frame->tf_dsr & CMMU_DSR_WE) { /* write fault */
/*
* This could be a write protection fault or an
* exception to set the used and modified bits
* in the pte. Basically, if we got a write error,
* then we already have a pte entry that faulted
* in from a previous seg fault or page fault.
* Get the pte and check the status of the
* modified and valid bits to determine if this
* indeed a real write fault. XXX smurph
*/
pte = pmap_pte(map->pmap, va);
#ifdef DEBUG
if (pte == PT_ENTRY_NULL)
panic("NULL pte on write fault??");
#endif
if (!(*pte & PG_M) && !(*pte & PG_RO)) {
/* Set modified bit and try the write again. */
#ifdef TRAPDEBUG
printf("Corrected kernel write fault, map %x pte %x\n",
map->pmap, *pte);
#endif
*pte |= PG_M;
return;
#if 1 /* shouldn't happen */
} else {
/* must be a real wp fault */
#ifdef TRAPDEBUG
printf("Uncorrected kernel write fault, map %x pte %x\n",
map->pmap, *pte);
#endif
if ((pcb_onfault = p->p_addr->u_pcb.pcb_onfault) != 0)
p->p_addr->u_pcb.pcb_onfault = 0;
result = uvm_fault(map, va, VM_FAULT_INVALID, ftype);
p->p_addr->u_pcb.pcb_onfault = pcb_onfault;
if (result == 0)
return;
#endif
}
}
panictrap(frame->tf_vector, frame);
/* NOTREACHED */
case T_INSTFLT+T_USER:
/* User mode instruction access fault */
/* FALLTHROUGH */
case T_DATAFLT+T_USER:
m88110_user_fault:
if (type == T_INSTFLT+T_USER) {
ftype = VM_PROT_READ;
fault_code = VM_PROT_READ;
#ifdef TRAPDEBUG
printf("User Instruction fault exip %x isr %x ilar %x\n",
frame->tf_exip, frame->tf_isr, frame->tf_ilar);
#endif
} else {
fault_addr = frame->tf_dlar;
if (frame->tf_dsr & CMMU_DSR_RW) {
ftype = VM_PROT_READ;
fault_code = VM_PROT_READ;
} else {
ftype = VM_PROT_READ|VM_PROT_WRITE;
fault_code = VM_PROT_WRITE;
}
#ifdef TRAPDEBUG
printf("User Data access fault exip %x dsr %x dlar %x\n",
frame->tf_exip, frame->tf_dsr, frame->tf_dlar);
#endif
}
va = trunc_page((vaddr_t)fault_addr);
vm = p->p_vmspace;
map = &vm->vm_map;
if ((pcb_onfault = p->p_addr->u_pcb.pcb_onfault) != 0)
p->p_addr->u_pcb.pcb_onfault = 0;
/*
* Call uvm_fault() to resolve non-bus error faults
* whenever possible.
*/
if (type == T_DATAFLT+T_USER) {
/* data faults */
if (frame->tf_dsr & CMMU_DSR_BE) {
/* bus error */
result = EACCES;
} else
if (frame->tf_dsr & (CMMU_DSR_SI | CMMU_DSR_PI)) {
/* segment or page fault */
result = uvm_fault(map, va, VM_FAULT_INVALID, ftype);
p->p_addr->u_pcb.pcb_onfault = pcb_onfault;
if (result == EACCES)
result = EFAULT;
} else
if (frame->tf_dsr & (CMMU_DSR_CP | CMMU_DSR_WA)) {
/* copyback or write allocate error */
result = EACCES;
} else
if (frame->tf_dsr & CMMU_DSR_WE) {
/* write fault */
/* This could be a write protection fault or an
* exception to set the used and modified bits
* in the pte. Basically, if we got a write
* error, then we already have a pte entry that
* faulted in from a previous seg fault or page
* fault.
* Get the pte and check the status of the
* modified and valid bits to determine if this
* indeed a real write fault. XXX smurph
*/
pte = pmap_pte(vm_map_pmap(map), va);
#ifdef DEBUG
if (pte == PT_ENTRY_NULL)
panic("NULL pte on write fault??");
#endif
if (!(*pte & PG_M) && !(*pte & PG_RO)) {
/*
* Set modified bit and try the
* write again.
*/
#ifdef TRAPDEBUG
printf("Corrected userland write fault, map %x pte %x\n",
map->pmap, *pte);
#endif
*pte |= PG_M;
/*
* invalidate ATCs to force
* table search
*/
set_dcmd(CMMU_DCMD_INV_UATC);
return;
} else {
/* must be a real wp fault */
#ifdef TRAPDEBUG
printf("Uncorrected userland write fault, map %x pte %x\n",
map->pmap, *pte);
#endif
result = uvm_fault(map, va, VM_FAULT_INVALID, ftype);
p->p_addr->u_pcb.pcb_onfault = pcb_onfault;
if (result == EACCES)
result = EFAULT;
}
} else {
#ifdef TRAPDEBUG
printf("Unexpected Data access fault dsr %x\n",
frame->tf_dsr);
#endif
panictrap(frame->tf_vector, frame);
}
} else {
/* instruction faults */
if (frame->tf_isr &
(CMMU_ISR_BE | CMMU_ISR_SP | CMMU_ISR_TBE)) {
/* bus error, supervisor protection */
result = EACCES;
} else
if (frame->tf_isr & (CMMU_ISR_SI | CMMU_ISR_PI)) {
/* segment or page fault */
result = uvm_fault(map, va, VM_FAULT_INVALID, ftype);
p->p_addr->u_pcb.pcb_onfault = pcb_onfault;
if (result == EACCES)
result = EFAULT;
} else {
#ifdef TRAPDEBUG
printf("Unexpected Instruction fault isr %x\n",
frame->tf_isr);
#endif
panictrap(frame->tf_vector, frame);
}
}
if ((caddr_t)va >= vm->vm_maxsaddr) {
if (result == 0) {
nss = btoc(USRSTACK - va);/* XXX check this */
if (nss > vm->vm_ssize)
vm->vm_ssize = nss;
}
}
/*
* This could be a fault caused in copyin*()
* while accessing user space.
*/
if (result != 0 && pcb_onfault != 0) {
frame->tf_exip = pcb_onfault;
/*
* Continue as if the fault had been resolved.
*/
result = 0;
}
if (result != 0) {
sig = result == EACCES ? SIGBUS : SIGSEGV;
fault_type = result == EACCES ?
BUS_ADRERR : SEGV_MAPERR;
}
break;
case T_MISALGNFLT+T_USER:
/* Fix any misaligned ld.d or st.d instructions */
sig = double_reg_fixup(frame);
fault_type = BUS_ADRALN;
break;
case T_PRIVINFLT+T_USER:
case T_ILLFLT+T_USER:
#ifndef DDB
case T_KDB_BREAK:
case T_KDB_ENTRY:
case T_KDB_TRACE:
#endif
case T_KDB_BREAK+T_USER:
case T_KDB_ENTRY+T_USER:
case T_KDB_TRACE+T_USER:
sig = SIGILL;
break;
case T_BNDFLT+T_USER:
sig = SIGFPE;
break;
case T_ZERODIV+T_USER:
sig = SIGFPE;
fault_type = FPE_INTDIV;
break;
case T_OVFFLT+T_USER:
sig = SIGFPE;
fault_type = FPE_INTOVF;
break;
case T_FPEPFLT+T_USER:
case T_FPEIFLT+T_USER:
sig = SIGFPE;
break;
case T_SIGSYS+T_USER:
sig = SIGSYS;
break;
case T_SIGTRAP+T_USER:
sig = SIGTRAP;
fault_type = TRAP_TRACE;
break;
case T_STEPBPT+T_USER:
#ifdef PTRACE
/*
* This trap is used by the kernel to support single-step
* debugging (although any user could generate this trap
* which should probably be handled differently). When a
* process is continued by a debugger with the PT_STEP
* function of ptrace (single step), the kernel inserts
* one or two breakpoints in the user process so that only
* one instruction (or two in the case of a delayed branch)
* is executed. When this breakpoint is hit, we get the
* T_STEPBPT trap.
*/
{
unsigned instr;
unsigned pc = PC_REGS(&frame->tf_regs);
/* read break instruction */
copyin((caddr_t)pc, &instr, sizeof(unsigned));
#if 0
printf("trap: %s (%d) breakpoint %x at %x: (adr %x ins %x)\n",
p->p_comm, p->p_pid, instr, pc,
p->p_md.md_ss_addr, p->p_md.md_ss_instr); /* XXX */
#endif
/* check and see if we got here by accident */
#ifdef notyet
if (p->p_md.md_ss_addr != pc || instr != SSBREAKPOINT) {
sig = SIGTRAP;
fault_type = TRAP_TRACE;
break;
}
#endif
/* restore original instruction and clear BP */
instr = p->p_md.md_ss_instr;
if (instr != 0)
ss_put_value(p, pc, instr, sizeof(instr));
p->p_md.md_ss_addr = 0;
p->p_md.md_ss_instr = 0;
sig = SIGTRAP;
fault_type = TRAP_BRKPT;
}
#else
sig = SIGTRAP;
fault_type = TRAP_TRACE;
#endif
break;
case T_USERBPT+T_USER:
/*
* This trap is meant to be used by debuggers to implement
* breakpoint debugging. When we get this trap, we just
* return a signal which gets caught by the debugger.
*/
sig = SIGTRAP;
fault_type = TRAP_BRKPT;
break;
case T_ASTFLT+T_USER:
uvmexp.softs++;
want_ast = 0;
if (p->p_flag & P_OWEUPC) {
p->p_flag &= ~P_OWEUPC;
ADDUPROF(p);
}
break;
}
/*
* If trap from supervisor mode, just return
*/
if (type < T_USER)
return;
if (sig) {
sv.sival_int = fault_addr;
trapsignal(p, sig, fault_code, fault_type, sv);
}
userret(p, frame, sticks);
}
void
m88100_trap(unsigned type, struct trapframe *frame)
{
struct proc *p;
struct vm_map *map;
vaddr_t va, pcb_onfault;
vm_prot_t ftype;
int fault_type, pbus_type;
u_long fault_code;
unsigned fault_addr;
struct vmspace *vm;
union sigval sv;
int result;
#ifdef DDB
int s;
u_int psr;
#endif
int sig = 0;
extern struct vm_map *kernel_map;
uvmexp.traps++;
if ((p = curproc) == NULL)
p = &proc0;
if (USERMODE(frame->tf_epsr)) {
type += T_USER;
p->p_md.md_tf = frame; /* for ptrace/signals */
}
fault_type = 0;
fault_code = 0;
fault_addr = frame->tf_sxip & XIP_ADDR;
switch (type) {
default:
panictrap(frame->tf_vector, frame);
break;
/*NOTREACHED*/
#if defined(DDB)
case T_KDB_BREAK:
s = splhigh();
set_psr((psr = get_psr()) & ~PSR_IND);
ddb_break_trap(T_KDB_BREAK, (db_regs_t*)frame);
set_psr(psr);
splx(s);
return;
case T_KDB_ENTRY:
s = splhigh();
set_psr((psr = get_psr()) & ~PSR_IND);
ddb_entry_trap(T_KDB_ENTRY, (db_regs_t*)frame);
set_psr(psr);
splx(s);
return;
#endif /* DDB */
case T_ILLFLT:
printf("Unimplemented opcode!\n");
panictrap(frame->tf_vector, frame);
break;
case T_INT:
case T_INT+T_USER:
curcpu()->ci_intrdepth++;
md_interrupt_func(T_INT, frame);
curcpu()->ci_intrdepth--;
return;
case T_MISALGNFLT:
printf("kernel misaligned access exception @ 0x%08x\n",
frame->tf_sxip);
panictrap(frame->tf_vector, frame);
break;
case T_INSTFLT:
/* kernel mode instruction access fault.
* Should never, never happen for a non-paged kernel.
*/
#ifdef TRAPDEBUG
pbus_type = CMMU_PFSR_FAULT(frame->tf_ipfsr);
printf("Kernel Instruction fault #%d (%s) v = 0x%x, frame 0x%x cpu %p\n",
pbus_type, pbus_exception_type[pbus_type],
fault_addr, frame, frame->tf_cpu);
#endif
panictrap(frame->tf_vector, frame);
break;
case T_DATAFLT:
/* kernel mode data fault */
/* data fault on the user address? */
if ((frame->tf_dmt0 & DMT_DAS) == 0) {
type = T_DATAFLT + T_USER;
goto user_fault;
}
fault_addr = frame->tf_dma0;
if (frame->tf_dmt0 & (DMT_WRITE|DMT_LOCKBAR)) {
ftype = VM_PROT_READ|VM_PROT_WRITE;
fault_code = VM_PROT_WRITE;
} else {
ftype = VM_PROT_READ;
fault_code = VM_PROT_READ;
}
va = trunc_page((vaddr_t)fault_addr);
if (va == 0) {
panic("trap: bad kernel access at %x", fault_addr);
}
KERNEL_LOCK(LK_CANRECURSE | LK_EXCLUSIVE);
vm = p->p_vmspace;
map = kernel_map;
pbus_type = CMMU_PFSR_FAULT(frame->tf_dpfsr);
#ifdef TRAPDEBUG
printf("Kernel Data access fault #%d (%s) v = 0x%x, frame 0x%x cpu %p\n",
pbus_type, pbus_exception_type[pbus_type],
fault_addr, frame, frame->tf_cpu);
#endif
switch (pbus_type) {
case CMMU_PFSR_SUCCESS:
/*
* The fault was resolved. Call data_access_emulation
* to drain the data unit pipe line and reset dmt0
* so that trap won't get called again.
*/
data_access_emulation((unsigned *)frame);
frame->tf_dpfsr = 0;
frame->tf_dmt0 = 0;
KERNEL_UNLOCK();
return;
case CMMU_PFSR_SFAULT:
case CMMU_PFSR_PFAULT:
if ((pcb_onfault = p->p_addr->u_pcb.pcb_onfault) != 0)
p->p_addr->u_pcb.pcb_onfault = 0;
result = uvm_fault(map, va, VM_FAULT_INVALID, ftype);
p->p_addr->u_pcb.pcb_onfault = pcb_onfault;
if (result == 0) {
/*
* We could resolve the fault. Call
* data_access_emulation to drain the data
* unit pipe line and reset dmt0 so that trap
* won't get called again.
*/
data_access_emulation((unsigned *)frame);
frame->tf_dpfsr = 0;
frame->tf_dmt0 = 0;
KERNEL_UNLOCK();
return;
}
break;
}
#ifdef TRAPDEBUG
printf("PBUS Fault %d (%s) va = 0x%x\n", pbus_type,
pbus_exception_type[pbus_type], va);
#endif
KERNEL_UNLOCK();
panictrap(frame->tf_vector, frame);
/* NOTREACHED */
case T_INSTFLT+T_USER:
/* User mode instruction access fault */
/* FALLTHROUGH */
case T_DATAFLT+T_USER:
user_fault:
if (type == T_INSTFLT + T_USER) {
pbus_type = CMMU_PFSR_FAULT(frame->tf_ipfsr);
#ifdef TRAPDEBUG
printf("User Instruction fault #%d (%s) v = 0x%x, frame 0x%x cpu %p\n",
pbus_type, pbus_exception_type[pbus_type],
fault_addr, frame, frame->tf_cpu);
#endif
} else {
fault_addr = frame->tf_dma0;
pbus_type = CMMU_PFSR_FAULT(frame->tf_dpfsr);
#ifdef TRAPDEBUG
printf("User Data access fault #%d (%s) v = 0x%x, frame 0x%x cpu %p\n",
pbus_type, pbus_exception_type[pbus_type],
fault_addr, frame, frame->tf_cpu);
#endif
}
if (frame->tf_dmt0 & (DMT_WRITE | DMT_LOCKBAR)) {
ftype = VM_PROT_READ | VM_PROT_WRITE;
fault_code = VM_PROT_WRITE;
} else {
ftype = VM_PROT_READ;
fault_code = VM_PROT_READ;
}
va = trunc_page((vaddr_t)fault_addr);
KERNEL_PROC_LOCK(p);
vm = p->p_vmspace;
map = &vm->vm_map;
if ((pcb_onfault = p->p_addr->u_pcb.pcb_onfault) != 0)
p->p_addr->u_pcb.pcb_onfault = 0;
/* Call uvm_fault() to resolve non-bus error faults */
switch (pbus_type) {
case CMMU_PFSR_SUCCESS:
result = 0;
break;
case CMMU_PFSR_BERROR:
result = EACCES;
break;
default:
result = uvm_fault(map, va, VM_FAULT_INVALID, ftype);
break;
}
p->p_addr->u_pcb.pcb_onfault = pcb_onfault;
if ((caddr_t)va >= vm->vm_maxsaddr) {
if (result == 0)
uvm_grow(p, va);
else if (result == EACCES)
result = EFAULT;
}
KERNEL_PROC_UNLOCK(p);
/*
* This could be a fault caused in copyin*()
* while accessing user space.
*/
if (result != 0 && pcb_onfault != 0) {
frame->tf_snip = pcb_onfault | NIP_V;
frame->tf_sfip = (pcb_onfault + 4) | FIP_V;
frame->tf_sxip = 0;
/*
* Continue as if the fault had been resolved, but
* do not try to complete the faulting access.
*/
frame->tf_dmt0 |= DMT_SKIP;
result = 0;
}
if (result == 0) {
if (type == T_DATAFLT+T_USER) {
/*
* We could resolve the fault. Call
* data_access_emulation to drain the data unit
* pipe line and reset dmt0 so that trap won't
* get called again.
*/
data_access_emulation((unsigned *)frame);
frame->tf_dpfsr = 0;
frame->tf_dmt0 = 0;
} else {
/*
* back up SXIP, SNIP,
* clearing the Error bit
*/
frame->tf_sfip = frame->tf_snip & ~FIP_E;
frame->tf_snip = frame->tf_sxip & ~NIP_E;
frame->tf_ipfsr = 0;
}
} else {
sig = result == EACCES ? SIGBUS : SIGSEGV;
fault_type = result == EACCES ?
BUS_ADRERR : SEGV_MAPERR;
}
break;
case T_MISALGNFLT+T_USER:
/* Fix any misaligned ld.d or st.d instructions */
sig = double_reg_fixup(frame);
fault_type = BUS_ADRALN;
break;
case T_PRIVINFLT+T_USER:
case T_ILLFLT+T_USER:
#ifndef DDB
case T_KDB_BREAK:
case T_KDB_ENTRY:
#endif
case T_KDB_BREAK+T_USER:
case T_KDB_ENTRY+T_USER:
case T_KDB_TRACE:
case T_KDB_TRACE+T_USER:
sig = SIGILL;
break;
case T_BNDFLT+T_USER:
sig = SIGFPE;
break;
case T_ZERODIV+T_USER:
sig = SIGFPE;
fault_type = FPE_INTDIV;
break;
case T_OVFFLT+T_USER:
sig = SIGFPE;
fault_type = FPE_INTOVF;
break;
case T_FPEPFLT+T_USER:
sig = SIGFPE;
break;
case T_SIGSYS+T_USER:
sig = SIGSYS;
break;
case T_STEPBPT+T_USER:
#ifdef PTRACE
/*
* This trap is used by the kernel to support single-step
* debugging (although any user could generate this trap
* which should probably be handled differently). When a
* process is continued by a debugger with the PT_STEP
* function of ptrace (single step), the kernel inserts
* one or two breakpoints in the user process so that only
* one instruction (or two in the case of a delayed branch)
* is executed. When this breakpoint is hit, we get the
* T_STEPBPT trap.
*/
{
u_int instr;
vaddr_t pc = PC_REGS(&frame->tf_regs);
/* read break instruction */
copyin((caddr_t)pc, &instr, sizeof(u_int));
/* check and see if we got here by accident */
if ((p->p_md.md_bp0va != pc &&
p->p_md.md_bp1va != pc) ||
instr != SSBREAKPOINT) {
sig = SIGTRAP;
fault_type = TRAP_TRACE;
break;
}
/* restore original instruction and clear breakpoint */
if (p->p_md.md_bp0va == pc) {
ss_put_value(p, pc, p->p_md.md_bp0save);
p->p_md.md_bp0va = 0;
}
if (p->p_md.md_bp1va == pc) {
ss_put_value(p, pc, p->p_md.md_bp1save);
p->p_md.md_bp1va = 0;
}
#if 1
frame->tf_sfip = frame->tf_snip;
frame->tf_snip = pc | NIP_V;
#endif
sig = SIGTRAP;
fault_type = TRAP_BRKPT;
}
#else
sig = SIGTRAP;
fault_type = TRAP_TRACE;
#endif
break;
case T_USERBPT+T_USER:
/*
* This trap is meant to be used by debuggers to implement
* breakpoint debugging. When we get this trap, we just
* return a signal which gets caught by the debugger.
*/
frame->tf_sfip = frame->tf_snip;
frame->tf_snip = frame->tf_sxip;
sig = SIGTRAP;
fault_type = TRAP_BRKPT;
break;
case T_ASTFLT+T_USER:
uvmexp.softs++;
p->p_md.md_astpending = 0;
if (p->p_flag & P_OWEUPC) {
KERNEL_PROC_LOCK(p);
ADDUPROF(p);
KERNEL_PROC_UNLOCK(p);
}
if (curcpu()->ci_want_resched)
preempt(NULL);
break;
}
/*
* If trap from supervisor mode, just return
*/
if (type < T_USER)
return;
if (sig) {
sv.sival_int = fault_addr;
KERNEL_PROC_LOCK(p);
trapsignal(p, sig, fault_code, fault_type, sv);
KERNEL_PROC_UNLOCK(p);
/*
* don't want multiple faults - we are going to
* deliver signal.
*/
frame->tf_dmt0 = 0;
frame->tf_ipfsr = frame->tf_dpfsr = 0;
}
userret(p);
}
void
m88100_trap(unsigned type, struct trapframe *frame)
{
struct proc *p;
u_quad_t sticks = 0;
struct vm_map *map;
vaddr_t va, pcb_onfault;
vm_prot_t ftype;
int fault_type, pbus_type;
u_long fault_code;
unsigned nss, fault_addr;
struct vmspace *vm;
union sigval sv;
int result;
#ifdef DDB
int s;
#endif
int sig = 0;
extern struct vm_map *kernel_map;
extern caddr_t guarded_access_start;
extern caddr_t guarded_access_end;
extern caddr_t guarded_access_bad;
uvmexp.traps++;
if ((p = curproc) == NULL)
p = &proc0;
if (USERMODE(frame->tf_epsr)) {
sticks = p->p_sticks;
type += T_USER;
p->p_md.md_tf = frame; /* for ptrace/signals */
}
fault_type = 0;
fault_code = 0;
fault_addr = frame->tf_sxip & XIP_ADDR;
switch (type) {
default:
panictrap(frame->tf_vector, frame);
break;
/*NOTREACHED*/
#if defined(DDB)
case T_KDB_BREAK:
s = splhigh();
db_enable_interrupt();
ddb_break_trap(T_KDB_BREAK, (db_regs_t*)frame);
db_disable_interrupt();
splx(s);
return;
case T_KDB_ENTRY:
s = splhigh();
db_enable_interrupt();
ddb_entry_trap(T_KDB_ENTRY, (db_regs_t*)frame);
db_disable_interrupt();
splx(s);
return;
#endif /* DDB */
case T_ILLFLT:
printf("Unimplemented opcode!\n");
panictrap(frame->tf_vector, frame);
break;
case T_INT:
case T_INT+T_USER:
/* This function pointer is set in machdep.c
It calls m188_ext_int or sbc_ext_int depending
on the value of brdtyp - smurph */
(*md.interrupt_func)(T_INT, frame);
return;
case T_MISALGNFLT:
printf("kernel misaligned access exception @ 0x%08x\n",
frame->tf_sxip);
panictrap(frame->tf_vector, frame);
break;
case T_INSTFLT:
/* kernel mode instruction access fault.
* Should never, never happen for a non-paged kernel.
*/
#ifdef TRAPDEBUG
pbus_type = CMMU_PFSR_FAULT(frame->tf_ipfsr);
printf("Kernel Instruction fault #%d (%s) v = 0x%x, frame 0x%x cpu %d\n",
pbus_type, pbus_exception_type[pbus_type],
fault_addr, frame, frame->tf_cpu);
#endif
panictrap(frame->tf_vector, frame);
break;
case T_DATAFLT:
/* kernel mode data fault */
/* data fault on the user address? */
if ((frame->tf_dmt0 & DMT_DAS) == 0) {
type = T_DATAFLT + T_USER;
goto user_fault;
}
fault_addr = frame->tf_dma0;
if (frame->tf_dmt0 & (DMT_WRITE|DMT_LOCKBAR)) {
ftype = VM_PROT_READ|VM_PROT_WRITE;
fault_code = VM_PROT_WRITE;
} else {
ftype = VM_PROT_READ;
fault_code = VM_PROT_READ;
}
va = trunc_page((vaddr_t)fault_addr);
if (va == 0) {
panic("trap: bad kernel access at %x", fault_addr);
}
vm = p->p_vmspace;
map = kernel_map;
pbus_type = CMMU_PFSR_FAULT(frame->tf_dpfsr);
#ifdef TRAPDEBUG
printf("Kernel Data access fault #%d (%s) v = 0x%x, frame 0x%x cpu %d\n",
pbus_type, pbus_exception_type[pbus_type],
fault_addr, frame, frame->tf_cpu);
#endif
switch (pbus_type) {
case CMMU_PFSR_BERROR:
/*
* If it is a guarded access, bus error is OK.
*/
if ((frame->tf_sxip & XIP_ADDR) >=
(unsigned)&guarded_access_start &&
(frame->tf_sxip & XIP_ADDR) <=
(unsigned)&guarded_access_end) {
frame->tf_snip =
((unsigned)&guarded_access_bad ) | NIP_V;
frame->tf_sfip =
((unsigned)&guarded_access_bad + 4) | FIP_V;
frame->tf_sxip = 0;
/* We sort of resolved the fault ourselves
* because we know where it came from
* [guarded_access()]. But we must still think
* about the other possible transactions in
* dmt1 & dmt2. Mark dmt0 so that
* data_access_emulation skips it. XXX smurph
*/
frame->tf_dmt0 |= DMT_SKIP;
data_access_emulation((unsigned *)frame);
frame->tf_dpfsr = 0;
frame->tf_dmt0 = 0;
return;
}
break;
case CMMU_PFSR_SUCCESS:
/*
* The fault was resolved. Call data_access_emulation
* to drain the data unit pipe line and reset dmt0
* so that trap won't get called again.
*/
data_access_emulation((unsigned *)frame);
frame->tf_dpfsr = 0;
frame->tf_dmt0 = 0;
return;
case CMMU_PFSR_SFAULT:
case CMMU_PFSR_PFAULT:
if ((pcb_onfault = p->p_addr->u_pcb.pcb_onfault) != 0)
p->p_addr->u_pcb.pcb_onfault = 0;
result = uvm_fault(map, va, VM_FAULT_INVALID, ftype);
p->p_addr->u_pcb.pcb_onfault = pcb_onfault;
if (result == 0) {
/*
* We could resolve the fault. Call
* data_access_emulation to drain the data
* unit pipe line and reset dmt0 so that trap
* won't get called again.
*/
data_access_emulation((unsigned *)frame);
frame->tf_dpfsr = 0;
frame->tf_dmt0 = 0;
return;
}
break;
}
#ifdef TRAPDEBUG
printf("PBUS Fault %d (%s) va = 0x%x\n", pbus_type,
pbus_exception_type[pbus_type], va);
#endif
panictrap(frame->tf_vector, frame);
/* NOTREACHED */
case T_INSTFLT+T_USER:
/* User mode instruction access fault */
/* FALLTHROUGH */
case T_DATAFLT+T_USER:
user_fault:
if (type == T_INSTFLT + T_USER) {
pbus_type = CMMU_PFSR_FAULT(frame->tf_ipfsr);
#ifdef TRAPDEBUG
printf("User Instruction fault #%d (%s) v = 0x%x, frame 0x%x cpu %d\n",
pbus_type, pbus_exception_type[pbus_type],
fault_addr, frame, frame->tf_cpu);
#endif
} else {
fault_addr = frame->tf_dma0;
pbus_type = CMMU_PFSR_FAULT(frame->tf_dpfsr);
#ifdef TRAPDEBUG
printf("User Data access fault #%d (%s) v = 0x%x, frame 0x%x cpu %d\n",
pbus_type, pbus_exception_type[pbus_type],
fault_addr, frame, frame->tf_cpu);
#endif
}
if (frame->tf_dmt0 & (DMT_WRITE | DMT_LOCKBAR)) {
ftype = VM_PROT_READ | VM_PROT_WRITE;
fault_code = VM_PROT_WRITE;
} else {
ftype = VM_PROT_READ;
fault_code = VM_PROT_READ;
}
va = trunc_page((vaddr_t)fault_addr);
vm = p->p_vmspace;
map = &vm->vm_map;
if ((pcb_onfault = p->p_addr->u_pcb.pcb_onfault) != 0)
p->p_addr->u_pcb.pcb_onfault = 0;
/* Call uvm_fault() to resolve non-bus error faults */
switch (pbus_type) {
case CMMU_PFSR_SUCCESS:
result = 0;
break;
case CMMU_PFSR_BERROR:
result = EACCES;
break;
default:
result = uvm_fault(map, va, VM_FAULT_INVALID, ftype);
if (result == EACCES)
result = EFAULT;
break;
}
p->p_addr->u_pcb.pcb_onfault = pcb_onfault;
if ((caddr_t)va >= vm->vm_maxsaddr) {
if (result == 0) {
nss = btoc(USRSTACK - va);/* XXX check this */
if (nss > vm->vm_ssize)
vm->vm_ssize = nss;
}
}
/*
* This could be a fault caused in copyin*()
* while accessing user space.
*/
if (result != 0 && pcb_onfault != 0) {
frame->tf_snip = pcb_onfault | NIP_V;
frame->tf_sfip = (pcb_onfault + 4) | FIP_V;
frame->tf_sxip = 0;
/*
* Continue as if the fault had been resolved, but
* do not try to complete the faulting access.
*/
frame->tf_dmt0 |= DMT_SKIP;
result = 0;
}
if (result == 0) {
if (type == T_DATAFLT+T_USER) {
/*
* We could resolve the fault. Call
* data_access_emulation to drain the data unit
* pipe line and reset dmt0 so that trap won't
* get called again.
*/
data_access_emulation((unsigned *)frame);
frame->tf_dpfsr = 0;
frame->tf_dmt0 = 0;
} else {
/*
* back up SXIP, SNIP,
* clearing the Error bit
*/
frame->tf_sfip = frame->tf_snip & ~FIP_E;
frame->tf_snip = frame->tf_sxip & ~NIP_E;
frame->tf_ipfsr = 0;
}
} else {
sig = result == EACCES ? SIGBUS : SIGSEGV;
fault_type = result == EACCES ?
BUS_ADRERR : SEGV_MAPERR;
}
break;
case T_MISALGNFLT+T_USER:
/* Fix any misaligned ld.d or st.d instructions */
sig = double_reg_fixup(frame);
fault_type = BUS_ADRALN;
break;
case T_PRIVINFLT+T_USER:
case T_ILLFLT+T_USER:
#ifndef DDB
case T_KDB_BREAK:
case T_KDB_ENTRY:
#endif
case T_KDB_BREAK+T_USER:
case T_KDB_ENTRY+T_USER:
case T_KDB_TRACE:
case T_KDB_TRACE+T_USER:
sig = SIGILL;
break;
case T_BNDFLT+T_USER:
sig = SIGFPE;
break;
case T_ZERODIV+T_USER:
sig = SIGFPE;
fault_type = FPE_INTDIV;
break;
case T_OVFFLT+T_USER:
sig = SIGFPE;
fault_type = FPE_INTOVF;
break;
case T_FPEPFLT+T_USER:
case T_FPEIFLT+T_USER:
sig = SIGFPE;
break;
case T_SIGSYS+T_USER:
sig = SIGSYS;
break;
case T_SIGTRAP+T_USER:
sig = SIGTRAP;
fault_type = TRAP_TRACE;
break;
case T_STEPBPT+T_USER:
#ifdef PTRACE
/*
* This trap is used by the kernel to support single-step
* debugging (although any user could generate this trap
* which should probably be handled differently). When a
* process is continued by a debugger with the PT_STEP
* function of ptrace (single step), the kernel inserts
* one or two breakpoints in the user process so that only
* one instruction (or two in the case of a delayed branch)
* is executed. When this breakpoint is hit, we get the
* T_STEPBPT trap.
*/
{
unsigned va;
unsigned instr;
unsigned pc = PC_REGS(&frame->tf_regs);
/* read break instruction */
copyin((caddr_t)pc, &instr, sizeof(unsigned));
#if 0
printf("trap: %s (%d) breakpoint %x at %x: (adr %x ins %x)\n",
p->p_comm, p->p_pid, instr, pc,
p->p_md.md_ss_addr, p->p_md.md_ss_instr); /* XXX */
#endif
/* check and see if we got here by accident */
if ((p->p_md.md_ss_addr != pc &&
p->p_md.md_ss_taken_addr != pc) ||
instr != SSBREAKPOINT) {
sig = SIGTRAP;
fault_type = TRAP_TRACE;
break;
}
/* restore original instruction and clear BP */
va = p->p_md.md_ss_addr;
if (va != 0) {
instr = p->p_md.md_ss_instr;
ss_put_value(p, va, instr, sizeof(instr));
}
/* branch taken instruction */
instr = p->p_md.md_ss_taken_instr;
if (instr != 0) {
va = p->p_md.md_ss_taken_addr;
ss_put_value(p, va, instr, sizeof(instr));
}
#if 1
frame->tf_sfip = frame->tf_snip;
frame->tf_snip = pc | NIP_V;
#endif
p->p_md.md_ss_addr = 0;
p->p_md.md_ss_instr = 0;
p->p_md.md_ss_taken_addr = 0;
p->p_md.md_ss_taken_instr = 0;
sig = SIGTRAP;
fault_type = TRAP_BRKPT;
}
#else
sig = SIGTRAP;
fault_type = TRAP_TRACE;
#endif
break;
case T_USERBPT+T_USER:
/*
* This trap is meant to be used by debuggers to implement
* breakpoint debugging. When we get this trap, we just
* return a signal which gets caught by the debugger.
*/
frame->tf_sfip = frame->tf_snip;
frame->tf_snip = frame->tf_sxip;
sig = SIGTRAP;
fault_type = TRAP_BRKPT;
break;
case T_ASTFLT+T_USER:
uvmexp.softs++;
want_ast = 0;
if (p->p_flag & P_OWEUPC) {
p->p_flag &= ~P_OWEUPC;
ADDUPROF(p);
}
break;
}
/*
* If trap from supervisor mode, just return
*/
if (type < T_USER)
return;
if (sig) {
sv.sival_int = fault_addr;
trapsignal(p, sig, fault_code, fault_type, sv);
/*
* don't want multiple faults - we are going to
* deliver signal.
*/
frame->tf_dmt0 = 0;
frame->tf_ipfsr = frame->tf_dpfsr = 0;
}
userret(p, frame, sticks);
}
void
m88110_trap(u_int type, struct trapframe *frame)
{
struct proc *p;
struct vm_map *map;
vaddr_t va, pcb_onfault;
vm_prot_t ftype;
int fault_type;
u_long fault_code;
vaddr_t fault_addr;
struct vmspace *vm;
union sigval sv;
int result;
#ifdef DDB
int s;
u_int psr;
#endif
int sig = 0;
uvmexp.traps++;
if ((p = curproc) == NULL)
p = &proc0;
fault_type = SI_NOINFO;
fault_code = 0;
fault_addr = frame->tf_exip & XIP_ADDR;
/*
* 88110 errata #16 (4.2) or #3 (5.1.1):
* ``bsr, br, bcnd, jsr and jmp instructions with the .n extension
* can cause the enip value to be incremented by 4 incorrectly
* if the instruction in the delay slot is the first word of a
* page which misses in the mmu and results in a hardware
* tablewalk which encounters an exception or an invalid
* descriptor. The exip value in this case will point to the
* first word of the page, and the D bit will be set.
*
* Note: if the instruction is a jsr.n r1, r1 will be overwritten
* with erroneous data. Therefore, no recovery is possible. Do
* not allow this instruction to occupy the last word of a page.
*
* Suggested fix: recover in general by backing up the exip by 4
* and clearing the delay bit before an rte when the lower 3 hex
* digits of the exip are 001.''
*/
if ((frame->tf_exip & PAGE_MASK) == 0x00000001 && type == T_INSTFLT) {
u_int instr;
/*
* Note that we have initialized fault_addr above, so that
* signals provide the correct address if necessary.
*/
frame->tf_exip = (frame->tf_exip & ~1) - 4;
/*
* Check the instruction at the (backed up) exip.
* If it is a jsr.n, abort.
*/
if (!USERMODE(frame->tf_epsr)) {
instr = *(u_int *)fault_addr;
if (instr == 0xf400cc01)
panic("mc88110 errata #16, exip %p enip %p",
(frame->tf_exip + 4) | 1, frame->tf_enip);
} else {
/* copyin here should not fail */
if (copyin((const void *)frame->tf_exip, &instr,
sizeof instr) == 0 &&
instr == 0xf400cc01) {
uprintf("mc88110 errata #16, exip %p enip %p",
(frame->tf_exip + 4) | 1, frame->tf_enip);
sig = SIGILL;
}
}
}
if (USERMODE(frame->tf_epsr)) {
type += T_USER;
p->p_md.md_tf = frame; /* for ptrace/signals */
}
if (sig != 0)
goto deliver;
switch (type) {
default:
lose:
panictrap(frame->tf_vector, frame);
break;
/*NOTREACHED*/
#ifdef DEBUG
case T_110_DRM+T_USER:
case T_110_DRM:
printf("DMMU read miss: Hardware Table Searches should be enabled!\n");
goto lose;
case T_110_DWM+T_USER:
case T_110_DWM:
printf("DMMU write miss: Hardware Table Searches should be enabled!\n");
goto lose;
case T_110_IAM+T_USER:
case T_110_IAM:
printf("IMMU miss: Hardware Table Searches should be enabled!\n");
goto lose;
#endif
#ifdef DDB
case T_KDB_TRACE:
s = splhigh();
set_psr((psr = get_psr()) & ~PSR_IND);
ddb_break_trap(T_KDB_TRACE, (db_regs_t*)frame);
set_psr(psr);
splx(s);
return;
case T_KDB_BREAK:
s = splhigh();
set_psr((psr = get_psr()) & ~PSR_IND);
ddb_break_trap(T_KDB_BREAK, (db_regs_t*)frame);
set_psr(psr);
splx(s);
return;
case T_KDB_ENTRY:
s = splhigh();
set_psr((psr = get_psr()) & ~PSR_IND);
ddb_entry_trap(T_KDB_ENTRY, (db_regs_t*)frame);
set_psr(psr);
/* skip trap instruction */
m88110_skip_insn(frame);
splx(s);
return;
#endif /* DDB */
case T_ILLFLT:
/*
* The 88110 seems to trigger an instruction fault in
* supervisor mode when running the following sequence:
*
* bcnd.n cond, reg, 1f
* arithmetic insn
* ...
* the same exact arithmetic insn
* 1: another arithmetic insn stalled by the previous one
* ...
*
* The exception is reported with exip pointing to the
* branch address. I don't know, at this point, if there
* is any better workaround than the aggressive one
* implemented below; I don't see how this could relate to
* any of the 88110 errata (although it might be related to
* branch prediction).
*
* For the record, the exact sequence triggering the
* spurious exception is:
*
* bcnd.n eq0, r2, 1f
* or r25, r0, r22
* bsr somewhere
* or r25, r0, r22
* 1: cmp r13, r25, r20
*
* within the same cache line.
*
* Simply ignoring the exception and returning does not
* cause the exception to disappear. Clearing the
* instruction cache works, but on 88110+88410 systems,
* the 88410 needs to be invalidated as well. (note that
* the size passed to the flush routines does not matter
* since there is no way to flush a subset of the 88110
* I$ anyway)
*/
{
extern void *kernel_text, *etext;
if (fault_addr >= (vaddr_t)&kernel_text &&
fault_addr < (vaddr_t)&etext) {
cmmu_icache_inv(curcpu()->ci_cpuid,
trunc_page(fault_addr), PAGE_SIZE);
cmmu_cache_wbinv(curcpu()->ci_cpuid,
trunc_page(fault_addr), PAGE_SIZE);
return;
}
}
goto lose;
case T_MISALGNFLT:
printf("kernel misaligned access exception @%p\n",
frame->tf_exip);
goto lose;
case T_INSTFLT:
/* kernel mode instruction access fault.
* Should never, never happen for a non-paged kernel.
*/
#ifdef TRAPDEBUG
printf("Kernel Instruction fault exip %x isr %x ilar %x\n",
frame->tf_exip, frame->tf_isr, frame->tf_ilar);
#endif
goto lose;
case T_DATAFLT:
/* kernel mode data fault */
/* data fault on the user address? */
if ((frame->tf_dsr & CMMU_DSR_SU) == 0) {
KERNEL_LOCK();
goto m88110_user_fault;
}
#ifdef TRAPDEBUG
printf("Kernel Data access fault exip %x dsr %x dlar %x\n",
frame->tf_exip, frame->tf_dsr, frame->tf_dlar);
#endif
fault_addr = frame->tf_dlar;
if (frame->tf_dsr & CMMU_DSR_RW) {
ftype = VM_PROT_READ;
fault_code = VM_PROT_READ;
} else {
ftype = VM_PROT_READ|VM_PROT_WRITE;
fault_code = VM_PROT_WRITE;
}
va = trunc_page((vaddr_t)fault_addr);
KERNEL_LOCK();
vm = p->p_vmspace;
map = kernel_map;
if (frame->tf_dsr & (CMMU_DSR_SI | CMMU_DSR_PI)) {
/*
* On a segment or a page fault, call uvm_fault() to
* resolve the fault.
*/
if ((pcb_onfault = p->p_addr->u_pcb.pcb_onfault) != 0)
p->p_addr->u_pcb.pcb_onfault = 0;
result = uvm_fault(map, va, VM_FAULT_INVALID, ftype);
p->p_addr->u_pcb.pcb_onfault = pcb_onfault;
/*
* This could be a fault caused in copyout*()
* while accessing kernel space.
*/
if (result != 0 && pcb_onfault != 0) {
frame->tf_exip = pcb_onfault;
/*
* Continue as if the fault had been resolved.
*/
result = 0;
}
if (result == 0) {
KERNEL_UNLOCK();
return;
}
}
KERNEL_UNLOCK();
goto lose;
case T_INSTFLT+T_USER:
/* User mode instruction access fault */
/* FALLTHROUGH */
case T_DATAFLT+T_USER:
KERNEL_LOCK();
m88110_user_fault:
if (type == T_INSTFLT+T_USER) {
ftype = VM_PROT_READ;
fault_code = VM_PROT_READ;
#ifdef TRAPDEBUG
printf("User Instruction fault exip %x isr %x ilar %x\n",
frame->tf_exip, frame->tf_isr, frame->tf_ilar);
#endif
} else {
fault_addr = frame->tf_dlar;
if (frame->tf_dsr & CMMU_DSR_RW) {
ftype = VM_PROT_READ;
fault_code = VM_PROT_READ;
} else {
ftype = VM_PROT_READ|VM_PROT_WRITE;
fault_code = VM_PROT_WRITE;
}
#ifdef TRAPDEBUG
printf("User Data access fault exip %x dsr %x dlar %x\n",
frame->tf_exip, frame->tf_dsr, frame->tf_dlar);
#endif
}
va = trunc_page((vaddr_t)fault_addr);
vm = p->p_vmspace;
map = &vm->vm_map;
if ((pcb_onfault = p->p_addr->u_pcb.pcb_onfault) != 0)
p->p_addr->u_pcb.pcb_onfault = 0;
/*
* Call uvm_fault() to resolve non-bus error faults
* whenever possible.
*/
if (type == T_INSTFLT+T_USER) {
/* instruction faults */
if (frame->tf_isr &
(CMMU_ISR_BE | CMMU_ISR_SP | CMMU_ISR_TBE)) {
/* bus error, supervisor protection */
result = EACCES;
} else
if (frame->tf_isr & (CMMU_ISR_SI | CMMU_ISR_PI)) {
/* segment or page fault */
result = uvm_fault(map, va, VM_FAULT_INVALID, ftype);
} else {
#ifdef TRAPDEBUG
printf("Unexpected Instruction fault isr %x\n",
frame->tf_isr);
#endif
KERNEL_UNLOCK();
goto lose;
}
} else {
/* data faults */
if (frame->tf_dsr & CMMU_DSR_BE) {
/* bus error */
result = EACCES;
} else
if (frame->tf_dsr & (CMMU_DSR_SI | CMMU_DSR_PI)) {
/* segment or page fault */
result = uvm_fault(map, va, VM_FAULT_INVALID, ftype);
} else
if (frame->tf_dsr & (CMMU_DSR_CP | CMMU_DSR_WA)) {
/* copyback or write allocate error */
result = EACCES;
} else
if (frame->tf_dsr & CMMU_DSR_WE) {
/* write fault */
/* This could be a write protection fault or an
* exception to set the used and modified bits
* in the pte. Basically, if we got a write
* error, then we already have a pte entry that
* faulted in from a previous seg fault or page
* fault.
* Get the pte and check the status of the
* modified and valid bits to determine if this
* indeed a real write fault. XXX smurph
*/
if (pmap_set_modify(map->pmap, va)) {
#ifdef TRAPDEBUG
printf("Corrected userland write fault, pmap %p va %p\n",
map->pmap, va);
#endif
result = 0;
} else {
/* must be a real wp fault */
#ifdef TRAPDEBUG
printf("Uncorrected userland write fault, pmap %p va %p\n",
map->pmap, va);
#endif
result = uvm_fault(map, va, VM_FAULT_INVALID, ftype);
}
} else {
#ifdef TRAPDEBUG
printf("Unexpected Data access fault dsr %x\n",
frame->tf_dsr);
#endif
KERNEL_UNLOCK();
goto lose;
}
}
p->p_addr->u_pcb.pcb_onfault = pcb_onfault;
if ((caddr_t)va >= vm->vm_maxsaddr) {
if (result == 0)
uvm_grow(p, va);
else if (result == EACCES)
result = EFAULT;
}
KERNEL_UNLOCK();
/*
* This could be a fault caused in copyin*()
* while accessing user space.
*/
if (result != 0 && pcb_onfault != 0) {
frame->tf_exip = pcb_onfault;
/*
* Continue as if the fault had been resolved.
*/
result = 0;
}
if (result != 0) {
sig = result == EACCES ? SIGBUS : SIGSEGV;
fault_type = result == EACCES ?
BUS_ADRERR : SEGV_MAPERR;
}
break;
case T_MISALGNFLT+T_USER:
/* Fix any misaligned ld.d or st.d instructions */
sig = double_reg_fixup(frame);
fault_type = BUS_ADRALN;
if (sig == 0) {
/* skip recovered instruction */
m88110_skip_insn(frame);
goto userexit;
}
break;
case T_PRIVINFLT+T_USER:
fault_type = ILL_PRVREG;
/* FALLTHROUGH */
case T_ILLFLT+T_USER:
#ifndef DDB
case T_KDB_BREAK:
case T_KDB_ENTRY:
case T_KDB_TRACE:
#endif
case T_KDB_BREAK+T_USER:
case T_KDB_ENTRY+T_USER:
case T_KDB_TRACE+T_USER:
sig = SIGILL;
break;
case T_BNDFLT+T_USER:
sig = SIGFPE;
/* skip trap instruction */
m88110_skip_insn(frame);
break;
case T_ZERODIV+T_USER:
sig = SIGFPE;
fault_type = FPE_INTDIV;
/* skip trap instruction */
m88110_skip_insn(frame);
break;
case T_OVFFLT+T_USER:
sig = SIGFPE;
fault_type = FPE_INTOVF;
/* skip trap instruction */
m88110_skip_insn(frame);
break;
case T_FPEPFLT+T_USER:
m88110_fpu_exception(frame);
goto userexit;
case T_SIGSYS+T_USER:
sig = SIGSYS;
break;
case T_STEPBPT+T_USER:
#ifdef PTRACE
/*
* This trap is used by the kernel to support single-step
* debugging (although any user could generate this trap
* which should probably be handled differently). When a
* process is continued by a debugger with the PT_STEP
* function of ptrace (single step), the kernel inserts
* one or two breakpoints in the user process so that only
* one instruction (or two in the case of a delayed branch)
* is executed. When this breakpoint is hit, we get the
* T_STEPBPT trap.
*/
{
u_int instr;
vaddr_t pc = PC_REGS(&frame->tf_regs);
/* read break instruction */
copyin((caddr_t)pc, &instr, sizeof(u_int));
/* check and see if we got here by accident */
if ((p->p_md.md_bp0va != pc &&
p->p_md.md_bp1va != pc) ||
instr != SSBREAKPOINT) {
sig = SIGTRAP;
fault_type = TRAP_TRACE;
break;
}
/* restore original instruction and clear breakpoint */
if (p->p_md.md_bp0va == pc) {
ss_put_value(p, pc, p->p_md.md_bp0save);
p->p_md.md_bp0va = 0;
}
if (p->p_md.md_bp1va == pc) {
ss_put_value(p, pc, p->p_md.md_bp1save);
p->p_md.md_bp1va = 0;
}
sig = SIGTRAP;
fault_type = TRAP_BRKPT;
}
#else
sig = SIGTRAP;
fault_type = TRAP_TRACE;
#endif
break;
case T_USERBPT+T_USER:
/*
* This trap is meant to be used by debuggers to implement
* breakpoint debugging. When we get this trap, we just
* return a signal which gets caught by the debugger.
*/
sig = SIGTRAP;
fault_type = TRAP_BRKPT;
break;
}
/*
* If trap from supervisor mode, just return
*/
if (type < T_USER)
return;
if (sig) {
deliver:
sv.sival_ptr = (void *)fault_addr;
KERNEL_LOCK();
trapsignal(p, sig, fault_code, fault_type, sv);
KERNEL_UNLOCK();
}
userexit:
userret(p);
}
