/* $NetBSD: syscall.c,v 1.68 2021/02/01 19:31:34 skrll Exp $ */ /*- * Copyright (c) 2000, 2003 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Charles M. Hannum. * * 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. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``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 THE FOUNDATION OR CONTRIBUTORS * 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. */ /* * Copyright (c) 1994-1998 Mark Brinicombe. * Copyright (c) 1994 Brini. * All rights reserved. * * This code is derived from software written for Brini by Mark Brinicombe * * 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 Mark Brinicombe * for the NetBSD Project. * 4. The name of the company nor the name of the author may be used to * endorse or promote products derived from this software without specific * prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 THE AUTHOR OR CONTRIBUTORS 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. * * syscall entry handling * * Created : 09/11/94 */ #include __KERNEL_RCSID(0, "$NetBSD: syscall.c,v 1.68 2021/02/01 19:31:34 skrll Exp $"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include void swi_handler(trapframe_t *tf) { lwp_t * const l = curlwp; uint32_t insn; /* * Enable interrupts if they were enabled before the exception. * Since all syscalls *should* come from user mode it will always * be safe to enable them, but check anyway. */ KASSERT(VALID_PSR(tf->tf_spsr)); restore_interrupts(tf->tf_spsr & IF32_bits); #ifndef THUMB_CODE /* * Make sure the program counter is correctly aligned so we * don't take an alignment fault trying to read the opcode. */ if (__predict_false(((tf->tf_pc - INSN_SIZE) & 3) != 0)) { ksiginfo_t ksi; /* Give the user an illegal instruction signal. */ KSI_INIT_TRAP(&ksi); ksi.ksi_signo = SIGILL; ksi.ksi_code = ILL_ILLOPC; ksi.ksi_addr = (uint32_t *)(intptr_t) (tf->tf_pc-INSN_SIZE); #if 0 /* maybe one day we'll do emulations */ (*l->l_proc->p_emul->e_trapsignal)(l, &ksi); #else trapsignal(l, &ksi); #endif userret(l); return; } #endif #ifdef THUMB_CODE if (tf->tf_spsr & PSR_T_bit) { insn = 0xef000000 | SWI_OS_NETBSD | tf->tf_r0; tf->tf_r0 = tf->tf_ip; } else #endif { insn = read_insn(tf->tf_pc - INSN_SIZE, true); } KASSERTMSG(tf == lwp_trapframe(l), "tf %p vs %p", tf, lwp_trapframe(l)); #ifdef CPU_ARM7 /* * This code is only needed if we are including support for the ARM7 * core. Other CPUs do not need it but it does not hurt. */ /* * ARM700/ARM710 match sticks and sellotape job ... * * I know this affects GPS/VLSI ARM700/ARM710 + various ARM7500. * * On occasion data aborts are mishandled and end up calling * the swi vector. * * If the instruction that caused the exception is not a SWI * then we hit the bug. */ if ((insn & 0x0f000000) != 0x0f000000) { tf->tf_pc -= INSN_SIZE; curcpu()->ci_arm700bugcount.ev_count++; userret(l); return; } #endif /* CPU_ARM7 */ curcpu()->ci_data.cpu_nsyscall++; LWP_CACHE_CREDS(l, l->l_proc); (*l->l_proc->p_md.md_syscall)(tf, l, insn); } void syscall(struct trapframe *, lwp_t *, uint32_t); void syscall_intern(struct proc *p) { p->p_md.md_syscall = syscall; } void syscall(struct trapframe *tf, lwp_t *l, uint32_t insn) { struct proc * const p = l->l_proc; const struct sysent *callp; int error; u_int nargs, off = 0; register_t *args; uint64_t copyargs64[sizeof(register_t) * (2+SYS_MAXSYSARGS+1)/sizeof(uint64_t)]; register_t *copyargs = (register_t *)copyargs64; register_t rval[2]; ksiginfo_t ksi; const uint32_t os_mask = insn & SWI_OS_MASK; uint32_t code = insn & 0x000fffff; /* test new official and old unofficial NetBSD ranges */ if (__predict_false(os_mask != SWI_OS_NETBSD) && __predict_false(os_mask != 0)) { const uint32_t swi = __SHIFTOUT(insn, __BITS(23,0)); if (swi == SWI_IMB || swi == SWI_IMBrange) { userret(l); return; } /* Undefined so illegal instruction */ KSI_INIT_TRAP(&ksi); ksi.ksi_signo = SIGILL; ksi.ksi_code = ILL_ILLTRP; #ifdef THUMB_CODE if (tf->tf_spsr & PSR_T_bit) ksi.ksi_addr = (void *)(tf->tf_pc - THUMB_INSN_SIZE); else #endif ksi.ksi_addr = (void *)(tf->tf_pc - INSN_SIZE); ksi.ksi_trap = insn; trapsignal(l, &ksi); userret(l); return; } code &= (SYS_NSYSENT - 1); if (__predict_false(code == SYS_syscall)) { off = 1; code = tf->tf_r0; code &= (SYS_NSYSENT - 1); if (__predict_false(code == SYS_syscall)) { error = EINVAL; goto bad; } } callp = p->p_emul->e_sysent + code; nargs = callp->sy_narg; if ((nargs+off) > 4) { args = copyargs; memcpy(args, &tf->tf_r0+off, (4-off) * sizeof(register_t)); error = copyin((void *)tf->tf_usr_sp, args + 4 - off, (nargs - 4 + off) * sizeof(register_t)); if (error) goto bad; } else { args = &tf->tf_r0 + off; } error = sy_invoke(callp, l, args, rval, code); switch (error) { case 0: tf->tf_r0 = rval[0]; tf->tf_r1 = rval[1]; tf->tf_spsr &= ~PSR_C_bit; /* carry bit */ break; case ERESTART: /* * Reconstruct the pc to point at the swi. */ #ifdef THUMB_CODE if (tf->tf_spsr & PSR_T_bit) tf->tf_pc -= THUMB_INSN_SIZE; else #endif tf->tf_pc -= INSN_SIZE; break; case EJUSTRETURN: /* nothing to do */ break; default: bad: tf->tf_r0 = error; tf->tf_spsr |= PSR_C_bit; /* carry bit */ break; } userret(l); } void md_child_return(struct lwp *l) { struct trapframe * const tf = lwp_trapframe(l); tf->tf_r0 = 0; tf->tf_spsr &= ~PSR_C_bit; /* carry bit */ userret(l); } /* * Process the tail end of a posix_spawn() for the child. */ void cpu_spawn_return(struct lwp *l) { userret(l); }