1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 * 21 * Portions Copyright 2006-2008 John Birrell jb@freebsd.org 22 * 23 * $FreeBSD$ 24 * 25 */ 26 27 /* 28 * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 29 * Use is subject to license terms. 30 */ 31 32 #include <sys/cdefs.h> 33 #include <sys/param.h> 34 #include <sys/systm.h> 35 #include <sys/conf.h> 36 #include <sys/cpuvar.h> 37 #include <sys/fcntl.h> 38 #include <sys/filio.h> 39 #include <sys/kdb.h> 40 #include <sys/kernel.h> 41 #include <sys/kmem.h> 42 #include <sys/kthread.h> 43 #include <sys/limits.h> 44 #include <sys/linker.h> 45 #include <sys/lock.h> 46 #include <sys/malloc.h> 47 #include <sys/module.h> 48 #include <sys/mutex.h> 49 #include <sys/poll.h> 50 #include <sys/proc.h> 51 #include <sys/selinfo.h> 52 #include <sys/smp.h> 53 #include <sys/sysproto.h> 54 #include <sys/sysent.h> 55 #include <sys/uio.h> 56 #include <sys/unistd.h> 57 #include <machine/stdarg.h> 58 59 #include <sys/dtrace.h> 60 61 #ifdef LINUX_SYSTRACE 62 #if defined(__amd64__) 63 #include <amd64/linux32/linux.h> 64 #include <amd64/linux32/linux32_proto.h> 65 #include <amd64/linux32/linux32_syscalls.c> 66 #include <amd64/linux32/linux32_systrace_args.c> 67 #define MODNAME "linux32" 68 #elif defined(__i386__) 69 #include <i386/linux/linux.h> 70 #include <i386/linux/linux_proto.h> 71 #include <i386/linux/linux_syscalls.c> 72 #include <i386/linux/linux_systrace_args.c> 73 #define MODNAME "linux" 74 #else 75 #error Only i386 and amd64 are supported. 76 #endif 77 extern struct sysent linux_sysent[]; 78 #define MAXSYSCALL LINUX_SYS_MAXSYSCALL 79 #define SYSCALLNAMES linux_syscallnames 80 #define SYSENT linux_sysent 81 #elif defined(FREEBSD32_SYSTRACE) 82 /* 83 * The syscall arguments are processed into a DTrace argument array 84 * using a generated function. See sys/kern/makesyscalls.sh. 85 */ 86 #include <compat/freebsd32/freebsd32_proto.h> 87 #include <compat/freebsd32/freebsd32_util.h> 88 #include <compat/freebsd32/freebsd32_syscall.h> 89 #include <compat/freebsd32/freebsd32_systrace_args.c> 90 extern const char *freebsd32_syscallnames[]; 91 #define MODNAME "freebsd32" 92 #define MAXSYSCALL FREEBSD32_SYS_MAXSYSCALL 93 #define SYSCALLNAMES freebsd32_syscallnames 94 #define SYSENT freebsd32_sysent 95 #else 96 /* 97 * The syscall arguments are processed into a DTrace argument array 98 * using a generated function. See sys/kern/makesyscalls.sh. 99 */ 100 #include <sys/syscall.h> 101 #include <kern/systrace_args.c> 102 #define MODNAME "freebsd" 103 #define MAXSYSCALL SYS_MAXSYSCALL 104 #define SYSCALLNAMES syscallnames 105 #define SYSENT sysent 106 #endif 107 108 #define PROVNAME "syscall" 109 #define DEVNAME "dtrace/systrace/" MODNAME 110 111 #define SYSTRACE_ARTIFICIAL_FRAMES 1 112 113 #define SYSTRACE_SHIFT 16 114 #define SYSTRACE_ISENTRY(x) ((int)(x) >> SYSTRACE_SHIFT) 115 #define SYSTRACE_SYSNUM(x) ((int)(x) & ((1 << SYSTRACE_SHIFT) - 1)) 116 #define SYSTRACE_ENTRY(id) ((1 << SYSTRACE_SHIFT) | (id)) 117 #define SYSTRACE_RETURN(id) (id) 118 119 #if ((1 << SYSTRACE_SHIFT) <= MAXSYSCALL) 120 #error 1 << SYSTRACE_SHIFT must exceed number of system calls 121 #endif 122 123 static d_open_t systrace_open; 124 static int systrace_unload(void); 125 static void systrace_getargdesc(void *, dtrace_id_t, void *, dtrace_argdesc_t *); 126 static void systrace_provide(void *, dtrace_probedesc_t *); 127 static void systrace_destroy(void *, dtrace_id_t, void *); 128 static void systrace_enable(void *, dtrace_id_t, void *); 129 static void systrace_disable(void *, dtrace_id_t, void *); 130 static void systrace_load(void *); 131 132 static struct cdevsw systrace_cdevsw = { 133 .d_version = D_VERSION, 134 .d_open = systrace_open, 135 #ifdef LINUX_SYSTRACE 136 .d_name = "systrace_" MODNAME, 137 #else 138 .d_name = "systrace", 139 #endif 140 }; 141 142 static union { 143 const char **p_constnames; 144 char **pp_syscallnames; 145 } uglyhack = { SYSCALLNAMES }; 146 147 static dtrace_pattr_t systrace_attr = { 148 { DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON }, 149 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN }, 150 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_ISA }, 151 { DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON }, 152 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_ISA }, 153 }; 154 155 static dtrace_pops_t systrace_pops = { 156 systrace_provide, 157 NULL, 158 systrace_enable, 159 systrace_disable, 160 NULL, 161 NULL, 162 systrace_getargdesc, 163 NULL, 164 NULL, 165 systrace_destroy 166 }; 167 168 static struct cdev *systrace_cdev; 169 static dtrace_provider_id_t systrace_id; 170 171 #if !defined(LINUX_SYSTRACE) 172 /* 173 * Probe callback function. 174 * 175 * Note: This function is called for _all_ syscalls, regardless of which sysent 176 * array the syscall comes from. It could be a standard syscall or a 177 * compat syscall from something like Linux. 178 */ 179 static void 180 systrace_probe(u_int32_t id, int sysnum, struct sysent *sysent, void *params, 181 int ret) 182 { 183 int n_args = 0; 184 u_int64_t uargs[8]; 185 186 memset(uargs, 0, sizeof(uargs)); 187 /* 188 * Check if this syscall has an argument conversion function 189 * registered. 190 */ 191 if (params && sysent->sy_systrace_args_func != NULL) { 192 /* 193 * Convert the syscall parameters using the registered 194 * function. 195 */ 196 (*sysent->sy_systrace_args_func)(sysnum, params, uargs, &n_args); 197 } else if (params) { 198 /* 199 * Use the built-in system call argument conversion 200 * function to translate the syscall structure fields 201 * into the array of 64-bit values that DTrace 202 * expects. 203 */ 204 systrace_args(sysnum, params, uargs, &n_args); 205 } else { 206 /* 207 * Since params is NULL, this is a 'return' probe. 208 * Set arg0 and arg1 as the return value of this syscall. 209 */ 210 uargs[0] = uargs[1] = ret; 211 } 212 213 /* Process the probe using the converted argments. */ 214 dtrace_probe(id, uargs[0], uargs[1], uargs[2], uargs[3], uargs[4]); 215 } 216 #endif 217 218 static void 219 systrace_getargdesc(void *arg, dtrace_id_t id, void *parg, dtrace_argdesc_t *desc) 220 { 221 int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg); 222 223 systrace_setargdesc(sysnum, desc->dtargd_ndx, desc->dtargd_native, 224 sizeof(desc->dtargd_native)); 225 226 if (desc->dtargd_native[0] == '\0') 227 desc->dtargd_ndx = DTRACE_ARGNONE; 228 229 return; 230 } 231 232 static void 233 systrace_provide(void *arg, dtrace_probedesc_t *desc) 234 { 235 int i; 236 237 if (desc != NULL) 238 return; 239 240 for (i = 0; i < MAXSYSCALL; i++) { 241 if (dtrace_probe_lookup(systrace_id, MODNAME, 242 uglyhack.pp_syscallnames[i], "entry") != 0) 243 continue; 244 245 (void) dtrace_probe_create(systrace_id, MODNAME, uglyhack.pp_syscallnames[i], 246 "entry", SYSTRACE_ARTIFICIAL_FRAMES, 247 (void *)((uintptr_t)SYSTRACE_ENTRY(i))); 248 (void) dtrace_probe_create(systrace_id, MODNAME, uglyhack.pp_syscallnames[i], 249 "return", SYSTRACE_ARTIFICIAL_FRAMES, 250 (void *)((uintptr_t)SYSTRACE_RETURN(i))); 251 } 252 } 253 254 static void 255 systrace_destroy(void *arg, dtrace_id_t id, void *parg) 256 { 257 #ifdef DEBUG 258 int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg); 259 260 /* 261 * There's nothing to do here but assert that we have actually been 262 * disabled. 263 */ 264 if (SYSTRACE_ISENTRY((uintptr_t)parg)) { 265 ASSERT(sysent[sysnum].sy_entry == 0); 266 } else { 267 ASSERT(sysent[sysnum].sy_return == 0); 268 } 269 #endif 270 } 271 272 static void 273 systrace_enable(void *arg, dtrace_id_t id, void *parg) 274 { 275 int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg); 276 277 if (SYSENT[sysnum].sy_systrace_args_func == NULL) 278 SYSENT[sysnum].sy_systrace_args_func = systrace_args; 279 280 if (SYSTRACE_ISENTRY((uintptr_t)parg)) 281 SYSENT[sysnum].sy_entry = id; 282 else 283 SYSENT[sysnum].sy_return = id; 284 } 285 286 static void 287 systrace_disable(void *arg, dtrace_id_t id, void *parg) 288 { 289 int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg); 290 291 SYSENT[sysnum].sy_entry = 0; 292 SYSENT[sysnum].sy_return = 0; 293 } 294 295 static void 296 systrace_load(void *dummy) 297 { 298 /* Create the /dev/dtrace/systrace entry. */ 299 systrace_cdev = make_dev(&systrace_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600, 300 DEVNAME); 301 302 if (dtrace_register(PROVNAME, &systrace_attr, DTRACE_PRIV_USER, 303 NULL, &systrace_pops, NULL, &systrace_id) != 0) 304 return; 305 306 #if !defined(LINUX_SYSTRACE) 307 systrace_probe_func = systrace_probe; 308 #endif 309 } 310 311 312 static int 313 systrace_unload() 314 { 315 int error = 0; 316 317 if ((error = dtrace_unregister(systrace_id)) != 0) 318 return (error); 319 320 #if !defined(LINUX_SYSTRACE) 321 systrace_probe_func = NULL; 322 #endif 323 324 destroy_dev(systrace_cdev); 325 326 return (error); 327 } 328 329 static int 330 systrace_modevent(module_t mod __unused, int type, void *data __unused) 331 { 332 int error = 0; 333 334 switch (type) { 335 case MOD_LOAD: 336 break; 337 338 case MOD_UNLOAD: 339 break; 340 341 case MOD_SHUTDOWN: 342 break; 343 344 default: 345 error = EOPNOTSUPP; 346 break; 347 348 } 349 return (error); 350 } 351 352 static int 353 systrace_open(struct cdev *dev __unused, int oflags __unused, int devtype __unused, struct thread *td __unused) 354 { 355 return (0); 356 } 357 358 SYSINIT(systrace_load, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, systrace_load, NULL); 359 SYSUNINIT(systrace_unload, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, systrace_unload, NULL); 360 361 #ifdef LINUX_SYSTRACE 362 DEV_MODULE(systrace_linux32, systrace_modevent, NULL); 363 MODULE_VERSION(systrace_linux32, 1); 364 MODULE_DEPEND(systrace_linux32, linux, 1, 1, 1); 365 MODULE_DEPEND(systrace_linux32, dtrace, 1, 1, 1); 366 MODULE_DEPEND(systrace_linux32, opensolaris, 1, 1, 1); 367 #elif defined(FREEBSD32_SYSTRACE) 368 DEV_MODULE(systrace_freebsd32, systrace_modevent, NULL); 369 MODULE_VERSION(systrace_freebsd32, 1); 370 MODULE_DEPEND(systrace_freebsd32, dtrace, 1, 1, 1); 371 MODULE_DEPEND(systrace_freebsd32, opensolaris, 1, 1, 1); 372 #else 373 DEV_MODULE(systrace, systrace_modevent, NULL); 374 MODULE_VERSION(systrace, 1); 375 MODULE_DEPEND(systrace, dtrace, 1, 1, 1); 376 MODULE_DEPEND(systrace, opensolaris, 1, 1, 1); 377 #endif 378