/*- * 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 __FBSDID("$FreeBSD$"); #include "opt_fpu_emu.h" #include "opt_ktrace.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef KTRACE #include #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef FPU_EMU #include #endif #define FAULTBUF_LR 0 #define FAULTBUF_R1 1 #define FAULTBUF_R2 2 #define FAULTBUF_CR 3 #define FAULTBUF_CTR 4 #define FAULTBUF_XER 5 #define FAULTBUF_R13 6 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); int setfault(faultbuf); /* defined in locore.S */ /* Why are these not defined in a header? */ int badaddr(void *, size_t); int badaddr_read(void *, size_t, int *); struct powerpc_exception { u_int vector; char *name; }; static struct powerpc_exception powerpc_exceptions[] = { { EXC_CRIT, "critical input" }, { EXC_MCHK, "machine check" }, { EXC_DSI, "data storage interrupt" }, { EXC_ISI, "instruction storage interrupt" }, { EXC_EXI, "external interrupt" }, { EXC_ALI, "alignment" }, { EXC_PGM, "program" }, { EXC_SC, "system call" }, { EXC_APU, "auxiliary proc unavailable" }, { EXC_DECR, "decrementer" }, { EXC_FIT, "fixed-interval timer" }, { EXC_WDOG, "watchdog timer" }, { EXC_DTMISS, "data tlb miss" }, { EXC_ITMISS, "instruction tlb miss" }, { EXC_DEBUG, "debug" }, { EXC_PERF, "performance monitoring" }, { EXC_LAST, NULL } }; static const char * trapname(u_int vector) { struct powerpc_exception *pe; for (pe = powerpc_exceptions; pe->vector != EXC_LAST; pe++) { if (pe->vector == vector) return (pe->name); } return ("unknown"); } void trap(struct trapframe *frame) { struct thread *td; struct proc *p; int sig, type, user; ksiginfo_t ksi; PCPU_INC(cnt.v_trap); td = PCPU_GET(curthread); p = td->td_proc; type = frame->exc; sig = 0; user = (frame->srr1 & PSL_PR) ? 1 : 0; CTR3(KTR_TRAP, "trap: %s type=%s (%s)", p->p_comm, trapname(type), user ? "user" : "kernel"); if (user) { td->td_frame = frame; if (td->td_ucred != p->p_ucred) cred_update_thread(td); /* User Mode Traps */ switch (type) { case EXC_DSI: case EXC_ISI: sig = trap_pfault(frame, 1); break; case EXC_SC: syscall(frame); break; case EXC_ALI: if (fix_unaligned(td, frame) != 0) sig = SIGBUS; else frame->srr0 += 4; break; case EXC_DEBUG: /* Single stepping */ mtspr(SPR_DBSR, mfspr(SPR_DBSR)); frame->srr1 &= ~PSL_DE; frame->cpu.booke.dbcr0 &= ~(DBCR0_IDM || DBCR0_IC); sig = SIGTRAP; break; case EXC_PGM: /* Program exception */ #ifdef FPU_EMU sig = fpu_emulate(frame, (struct fpreg *)&td->td_pcb->pcb_fpu); #else /* XXX SIGILL for non-trap instructions. */ sig = SIGTRAP; #endif break; default: trap_fatal(frame); } } else { /* Kernel Mode Traps */ KASSERT(cold || td->td_ucred != NULL, ("kernel trap doesn't have ucred")); switch (type) { case EXC_DEBUG: mtspr(SPR_DBSR, mfspr(SPR_DBSR)); kdb_trap(frame->exc, 0, frame); return; case EXC_DSI: if (trap_pfault(frame, 0) == 0) return; break; case EXC_MCHK: if (handle_onfault(frame)) return; break; #ifdef KDB case EXC_PGM: if (frame->cpu.booke.esr & ESR_PTR) kdb_trap(EXC_PGM, 0, frame); return; #endif 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 = type; /* XXX, not POSIX */ /* ksi.ksi_addr = ? */ ksi.ksi_trapno = type; trapsignal(td, &ksi); } userret(td, frame); mtx_assert(&Giant, MA_NOTOWNED); } 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) { register_t va = 0; 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_DTMISS: case EXC_DSI: va = frame->cpu.booke.dear; break; case EXC_ITMISS: case EXC_ISI: va = frame->srr0; break; } printf(" virtual address = 0x%08x\n", va); printf(" srr0 = 0x%08x\n", frame->srr0); printf(" srr1 = 0x%08x\n", frame->srr1); printf(" curthread = %p\n", curthread); if (curthread != NULL) printf(" pid = %d, comm = %s\n", curthread->td_proc->p_pid, curthread->td_proc->p_comm); 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)[FAULTBUF_LR]; frame->fixreg[1] = (*fb)[FAULTBUF_R1]; frame->fixreg[2] = (*fb)[FAULTBUF_R2]; frame->fixreg[3] = 1; frame->cr = (*fb)[FAULTBUF_CR]; frame->ctr = (*fb)[FAULTBUF_CTR]; frame->xer = (*fb)[FAULTBUF_XER]; bcopy(&(*fb)[FAULTBUF_R13], &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; int error, n; 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 = *(u_int *) 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. */ params += sizeof(register_t); sa->code = *(u_int *) params; params += sizeof(register_t); n -= 2; } 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; bcopy(params, sa->args, n * sizeof(register_t)); if (sa->narg > n) { error = copyin(MOREARGS(frame->fixreg[1]), sa->args + n, (sa->narg - n) * sizeof(register_t)); } else error = 0; if (error == 0) { td->td_retval[0] = 0; td->td_retval[1] = frame->fixreg[FIRSTARG + 1]; } return (error); } void syscall(struct trapframe *frame) { struct thread *td; struct syscall_args sa; int error; td = PCPU_GET(curthread); td->td_frame = frame; error = syscallenter(td, &sa); syscallret(td, error, &sa); } 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; td = curthread; p = td->td_proc; if (frame->exc == EXC_ISI) { eva = frame->srr0; ftype = VM_PROT_READ | VM_PROT_EXECUTE; } else { eva = frame->cpu.booke.dear; if (frame->cpu.booke.esr & ESR_ST) ftype = VM_PROT_WRITE; else ftype = VM_PROT_READ; } if (user) { KASSERT(p->p_vmspace != NULL, ("trap_pfault: vmspace NULL")); map = &p->p_vmspace->vm_map; } else { if (eva < VM_MAXUSER_ADDRESS) { if (p->p_vmspace == NULL) return (SIGSEGV); map = &p->p_vmspace->vm_map; } 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); } 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 ((rv == KERN_PROTECTION_FAILURE) ? SIGBUS : SIGSEGV); } int badaddr(void *addr, size_t size) { return (badaddr_read(addr, size, NULL)); } int badaddr_read(void *addr, size_t size, int *rptr) { struct thread *td; faultbuf env; int x; /* Get rid of any stale machine checks that have been waiting. */ __asm __volatile ("sync; isync"); td = PCPU_GET(curthread); if (setfault(env)) { td->td_pcb->pcb_onfault = 0; __asm __volatile ("sync"); return (1); } __asm __volatile ("sync"); switch (size) { case 1: x = *(volatile int8_t *)addr; break; case 2: x = *(volatile int16_t *)addr; break; case 4: x = *(volatile int32_t *)addr; break; default: panic("badaddr: invalid size (%d)", size); } /* Make sure we took the machine check, if we caused one. */ __asm __volatile ("sync; isync"); td->td_pcb->pcb_onfault = 0; __asm __volatile ("sync"); /* To be sure. */ /* Use the value to avoid reorder. */ if (rptr) *rptr = x; return (0); } /* * 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) { #if 0 struct thread *fputhread; int indicator, reg; double *fpr; indicator = EXC_ALI_OPCODE_INDICATOR(frame->dsisr); switch (indicator) { case EXC_ALI_LFD: case EXC_ALI_STFD: reg = EXC_ALI_RST(frame->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->dar, fpr, sizeof(double)) != 0) return -1; enable_fpu(td); } else { if (copyout(fpr, (void *)frame->dar, sizeof(double)) != 0) return -1; } return 0; break; } #endif return (-1); } #ifdef KDB int db_trap_glue(struct trapframe *); int db_trap_glue(struct trapframe *tf) { if (!(tf->srr1 & PSL_PR)) return (kdb_trap(tf->exc, 0, tf)); return (0); } #endif