1 /* $NetBSD: linux_syscall.c,v 1.9 2006/07/19 21:11:39 ad 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 1.9 2006/07/19 21:11:39 ad Exp $"); 41 42 #include "opt_compat_linux.h" 43 44 #include <sys/param.h> 45 #include <sys/systm.h> 46 #include <sys/proc.h> 47 #include <sys/user.h> 48 #include <sys/signal.h> 49 #include <sys/sa.h> 50 #include <sys/savar.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 #include <compat/linux/common/linux_errno.h> 68 69 void linux_syscall_intern(struct proc *); 70 static void linux_syscall_plain(struct trapframe *); 71 static void linux_syscall_fancy(struct trapframe *); 72 73 void 74 linux_syscall_intern(struct proc *p) 75 { 76 77 if (trace_is_enabled(p)) 78 p->p_md.md_syscall = linux_syscall_fancy; 79 else 80 p->p_md.md_syscall = linux_syscall_plain; 81 } 82 83 /* 84 * syscall(frame): 85 * System call request from POSIX system call gate interface to kernel. 86 * Like trap(), argument is call by reference. 87 */ 88 static void 89 linux_syscall_plain(struct trapframe *frame) 90 { 91 caddr_t params; 92 const struct sysent *callp; 93 struct proc *p; 94 struct lwp *l; 95 int error; 96 size_t argsize, argoff; 97 register_t code, args[9], rval[2], *argp; 98 99 uvmexp.syscalls++; 100 l = curlwp; 101 p = l->l_proc; 102 LWP_CACHE_CREDS(l, p); 103 104 code = frame->tf_rax; 105 callp = p->p_emul->e_sysent; 106 argoff = 0; 107 argp = &args[0]; 108 109 code &= (LINUX_SYS_NSYSENT - 1); 110 callp += code; 111 112 argsize = (callp->sy_argsize >> 3) + argoff; 113 if (argsize) { 114 switch (MIN(argsize, 6)) { 115 case 6: 116 args[5] = frame->tf_r9; 117 case 5: 118 args[4] = frame->tf_r8; 119 case 4: 120 args[3] = frame->tf_r10; 121 case 3: 122 args[2] = frame->tf_rdx; 123 case 2: 124 args[1] = frame->tf_rsi; 125 case 1: 126 args[0] = frame->tf_rdi; 127 break; 128 default: 129 panic("impossible syscall argsize"); 130 } 131 if (argsize > 6) { 132 argsize -= 6; 133 params = (caddr_t)frame->tf_rsp + sizeof(register_t); 134 error = copyin(params, (caddr_t)&args[6], 135 argsize << 3); 136 if (error != 0) 137 goto bad; 138 } 139 } 140 141 rval[0] = 0; 142 rval[1] = 0; 143 KERNEL_PROC_LOCK(l); 144 error = (*callp->sy_call)(l, argp, rval); 145 KERNEL_PROC_UNLOCK(l); 146 147 switch (error) { 148 case 0: 149 frame->tf_rax = rval[0]; 150 frame->tf_rflags &= ~PSL_C; /* carry bit */ 151 break; 152 case ERESTART: 153 /* 154 * The offset to adjust the PC by depends on whether we entered 155 * the kernel through the trap or call gate. We pushed the 156 * size of the instruction into tf_err on entry. 157 */ 158 frame->tf_rip -= frame->tf_err; 159 break; 160 case EJUSTRETURN: 161 /* nothing to do */ 162 break; 163 default: 164 bad: 165 frame->tf_rax = native_to_linux_errno[error]; 166 frame->tf_rflags |= PSL_C; /* carry bit */ 167 break; 168 } 169 170 userret(l); 171 } 172 173 static void 174 linux_syscall_fancy(struct trapframe *frame) 175 { 176 caddr_t params; 177 const struct sysent *callp; 178 struct proc *p; 179 struct lwp *l; 180 int error; 181 size_t argsize, argoff; 182 register_t code, args[9], rval[2], *argp; 183 184 uvmexp.syscalls++; 185 l = curlwp; 186 p = l->l_proc; 187 LWP_CACHE_CREDS(l, p); 188 189 code = frame->tf_rax; 190 callp = p->p_emul->e_sysent; 191 argp = &args[0]; 192 argoff = 0; 193 194 code &= (SYS_NSYSENT - 1); 195 callp += code; 196 197 argsize = (callp->sy_argsize >> 3) + argoff; 198 if (argsize) { 199 switch (MIN(argsize, 6)) { 200 case 6: 201 args[5] = frame->tf_r9; 202 case 5: 203 args[4] = frame->tf_r8; 204 case 4: 205 args[3] = frame->tf_r10; 206 case 3: 207 args[2] = frame->tf_rdx; 208 case 2: 209 args[1] = frame->tf_rsi; 210 case 1: 211 args[0] = frame->tf_rdi; 212 break; 213 default: 214 panic("impossible syscall argsize"); 215 } 216 if (argsize > 6) { 217 argsize -= 6; 218 params = (caddr_t)frame->tf_rsp + sizeof(register_t); 219 error = copyin(params, (caddr_t)&args[6], 220 argsize << 3); 221 if (error != 0) 222 goto bad; 223 } 224 } 225 226 KERNEL_PROC_LOCK(l); 227 if ((error = trace_enter(l, code, code, NULL, argp)) != 0) 228 goto out; 229 230 rval[0] = 0; 231 rval[1] = 0; 232 error = (*callp->sy_call)(l, argp, rval); 233 out: 234 KERNEL_PROC_UNLOCK(l); 235 switch (error) { 236 case 0: 237 frame->tf_rax = rval[0]; 238 frame->tf_rflags &= ~PSL_C; /* carry bit */ 239 break; 240 case ERESTART: 241 /* 242 * The offset to adjust the PC by depends on whether we entered 243 * the kernel through the trap or call gate. We pushed the 244 * size of the instruction into tf_err on entry. 245 */ 246 frame->tf_rip -= frame->tf_err; 247 break; 248 case EJUSTRETURN: 249 /* nothing to do */ 250 break; 251 default: 252 bad: 253 frame->tf_rax = native_to_linux_errno[error]; 254 frame->tf_rflags |= PSL_C; /* carry bit */ 255 break; 256 } 257 258 trace_exit(l, code, argp, rval, error); 259 260 userret(l); 261 } 262