1 /* $NetBSD: linux_syscall.c,v 1.21 2008/02/06 22:12:41 dsl Exp $ */ 2 3 /*- 4 * Copyright (c) 1998, 2000 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Charles M. Hannum. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 #include <sys/cdefs.h> 40 __KERNEL_RCSID(0, "$NetBSD: linux_syscall.c,v 1.21 2008/02/06 22:12:41 dsl Exp $"); 41 42 #if defined(_KERNEL_OPT) 43 #include "opt_compat_linux.h" 44 #endif 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/proc.h> 49 #include <sys/user.h> 50 #include <sys/signal.h> 51 #include <sys/syscall.h> 52 53 #include <uvm/uvm_extern.h> 54 55 #include <machine/cpu.h> 56 #include <machine/psl.h> 57 #include <machine/userret.h> 58 59 #include <compat/linux/linux_syscall.h> 60 #include <compat/linux/common/linux_types.h> 61 #include <compat/linux/common/linux_errno.h> 62 #include <compat/linux/common/linux_signal.h> 63 #include <compat/linux/common/linux_siginfo.h> 64 #include <compat/linux/arch/amd64/linux_siginfo.h> 65 #include <compat/linux/arch/amd64/linux_syscall.h> 66 #include <compat/linux/arch/amd64/linux_machdep.h> 67 68 void linux_syscall_intern(struct proc *); 69 static void linux_syscall(struct trapframe *); 70 71 void 72 linux_syscall_intern(struct proc *p) 73 { 74 75 p->p_trace_enabled = trace_is_enabled(p); 76 p->p_md.md_syscall = linux_syscall; 77 } 78 79 /* 80 * syscall(frame): 81 * System call request from POSIX system call gate interface to kernel. 82 * Like trap(), argument is call by reference. 83 */ 84 static void 85 linux_syscall(struct trapframe *frame) 86 { 87 const struct sysent *callp; 88 struct proc *p; 89 struct lwp *l; 90 int error; 91 register_t code, rval[2]; 92 #define args (&frame->tf_rdi) 93 94 l = curlwp; 95 p = l->l_proc; 96 97 code = frame->tf_rax; 98 uvmexp.syscalls++; 99 100 LWP_CACHE_CREDS(l, p); 101 102 callp = p->p_emul->e_sysent; 103 104 code &= (SYS_NSYSENT - 1); 105 callp += code; 106 107 /* 108 * Linux system calls have a maximum of 6 arguments, they are 109 * already adjacent in the syscall trapframe. 110 */ 111 112 KERNEL_LOCK(1, l); 113 if (__predict_false(p->p_trace_enabled) 114 && (error = trace_enter(code, args, callp->sy_narg)) != 0) 115 goto out; 116 117 rval[0] = 0; 118 rval[1] = 0; 119 error = (*callp->sy_call)(l, args, rval); 120 out: 121 KERNEL_UNLOCK_LAST(l); 122 switch (error) { 123 case 0: 124 frame->tf_rax = rval[0]; 125 break; 126 case ERESTART: 127 /* 128 * The offset to adjust the PC by depends on whether we entered 129 * the kernel through the trap or call gate. We pushed the 130 * size of the instruction into tf_err on entry. 131 */ 132 frame->tf_rip -= frame->tf_err; 133 break; 134 case EJUSTRETURN: 135 /* nothing to do */ 136 break; 137 default: 138 error = native_to_linux_errno[error]; 139 frame->tf_rax = error; 140 break; 141 } 142 143 if (__predict_false(p->p_trace_enabled)) 144 trace_exit(code, rval, error); 145 146 userret(l); 147 } 148