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 24 /* 25 * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 26 * Use is subject to license terms. 27 */ 28 29 #include <sys/param.h> 30 #include <sys/systm.h> 31 #include <sys/conf.h> 32 #include <sys/cpuvar.h> 33 #include <sys/dtrace.h> 34 #include <sys/fcntl.h> 35 #include <sys/filio.h> 36 #include <sys/kdb.h> 37 #include <sys/kernel.h> 38 #include <sys/kmem.h> 39 #include <sys/kthread.h> 40 #include <sys/limits.h> 41 #include <sys/linker.h> 42 #include <sys/lock.h> 43 #include <sys/malloc.h> 44 #include <sys/module.h> 45 #include <sys/mutex.h> 46 #include <sys/poll.h> 47 #include <sys/proc.h> 48 #include <sys/selinfo.h> 49 #include <sys/smp.h> 50 #include <sys/stdarg.h> 51 #include <sys/sysent.h> 52 #include <sys/sysproto.h> 53 #include <sys/uio.h> 54 #include <sys/unistd.h> 55 56 #include <cddl/dev/dtrace/dtrace_cddl.h> 57 58 #ifdef LINUX_SYSTRACE 59 #if defined(__amd64__) 60 #include <amd64/linux/linux.h> 61 #include <amd64/linux/linux_proto.h> 62 #include <amd64/linux/linux_syscalls.c> 63 #include <amd64/linux/linux_systrace_args.c> 64 #elif defined(__i386__) 65 #include <i386/linux/linux.h> 66 #include <i386/linux/linux_proto.h> 67 #include <i386/linux/linux_syscalls.c> 68 #include <i386/linux/linux_systrace_args.c> 69 #else 70 #error Only i386 and amd64 are supported. 71 #endif 72 #define MODNAME "linux" 73 extern struct sysent linux_sysent[]; 74 #define MAXSYSCALL LINUX_SYS_MAXSYSCALL 75 #define SYSCALLNAMES linux_syscallnames 76 #define SYSENT linux_sysent 77 #elif defined(LINUX32_SYSTRACE) 78 #if defined(__amd64__) 79 #include <amd64/linux32/linux.h> 80 #include <amd64/linux32/linux32_proto.h> 81 #include <amd64/linux32/linux32_syscalls.c> 82 #include <amd64/linux32/linux32_systrace_args.c> 83 #else 84 #error Only amd64 is supported. 85 #endif 86 #define MODNAME "linux32" 87 extern struct sysent linux32_sysent[]; 88 #define MAXSYSCALL LINUX32_SYS_MAXSYSCALL 89 #define SYSCALLNAMES linux32_syscallnames 90 #define SYSENT linux32_sysent 91 #elif defined(FREEBSD32_SYSTRACE) 92 /* 93 * The syscall arguments are processed into a DTrace argument array 94 * using a generated function. See sys/tools/syscalls/README.md. 95 */ 96 #include <compat/freebsd32/freebsd32_proto.h> 97 #include <compat/freebsd32/freebsd32_util.h> 98 #include <compat/freebsd32/freebsd32_syscall.h> 99 #include <compat/freebsd32/freebsd32_systrace_args.c> 100 extern const char *freebsd32_syscallnames[]; 101 #define MODNAME "freebsd32" 102 #define MAXSYSCALL FREEBSD32_SYS_MAXSYSCALL 103 #define SYSCALLNAMES freebsd32_syscallnames 104 #define SYSENT freebsd32_sysent 105 #else 106 /* 107 * The syscall arguments are processed into a DTrace argument array 108 * using a generated function. See sys/tools/syscalls/README.md. 109 */ 110 #include <sys/syscall.h> 111 #include <kern/systrace_args.c> 112 #define MODNAME "freebsd" 113 #define MAXSYSCALL SYS_MAXSYSCALL 114 #define SYSCALLNAMES syscallnames 115 #define SYSENT sysent 116 #define NATIVE_ABI 117 #endif 118 119 #define PROVNAME "syscall" 120 #define DEVNAME "dtrace/systrace/" MODNAME 121 122 #define SYSTRACE_ARTIFICIAL_FRAMES 1 123 124 #define SYSTRACE_SHIFT 16 125 #define SYSTRACE_ISENTRY(x) ((int)(x) >> SYSTRACE_SHIFT) 126 #define SYSTRACE_SYSNUM(x) ((int)(x) & ((1 << SYSTRACE_SHIFT) - 1)) 127 #define SYSTRACE_ENTRY(id) ((1 << SYSTRACE_SHIFT) | (id)) 128 #define SYSTRACE_RETURN(id) (id) 129 130 #if ((1 << SYSTRACE_SHIFT) <= MAXSYSCALL) 131 #error 1 << SYSTRACE_SHIFT must exceed number of system calls 132 #endif 133 134 static int systrace_enabled_count; 135 136 static void systrace_load(void *); 137 static void systrace_unload(void *); 138 139 static void systrace_getargdesc(void *, dtrace_id_t, void *, 140 dtrace_argdesc_t *); 141 static uint64_t systrace_getargval(void *, dtrace_id_t, void *, int, int); 142 static void systrace_provide(void *, dtrace_probedesc_t *); 143 static void systrace_destroy(void *, dtrace_id_t, void *); 144 static void systrace_enable(void *, dtrace_id_t, void *); 145 static void systrace_disable(void *, dtrace_id_t, void *); 146 147 static union { 148 const char **p_constnames; 149 char **pp_syscallnames; 150 } uglyhack = { SYSCALLNAMES }; 151 152 static dtrace_pattr_t systrace_attr = { 153 { DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON }, 154 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN }, 155 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_ISA }, 156 { DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON }, 157 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_ISA }, 158 }; 159 160 static dtrace_pops_t systrace_pops = { 161 .dtps_provide = systrace_provide, 162 .dtps_provide_module = NULL, 163 .dtps_enable = systrace_enable, 164 .dtps_disable = systrace_disable, 165 .dtps_suspend = NULL, 166 .dtps_resume = NULL, 167 .dtps_getargdesc = systrace_getargdesc, 168 .dtps_getargval = systrace_getargval, 169 .dtps_usermode = NULL, 170 .dtps_destroy = systrace_destroy 171 }; 172 173 static dtrace_provider_id_t systrace_id; 174 175 #ifdef NATIVE_ABI 176 /* 177 * Probe callback function. 178 * 179 * Note: This function is called for _all_ syscalls, regardless of which sysent 180 * array the syscall comes from. It could be a standard syscall or a 181 * compat syscall from something like Linux. 182 */ 183 static void 184 systrace_probe(struct syscall_args *sa, enum systrace_probe_t type, int retval) 185 { 186 uint64_t uargs[nitems(sa->args)]; 187 dtrace_id_t id; 188 int n_args, sysnum; 189 190 sysnum = sa->code; 191 memset(uargs, 0, sizeof(uargs)); 192 193 if (type == SYSTRACE_ENTRY) { 194 if ((id = sa->callp->sy_entry) == DTRACE_IDNONE) 195 return; 196 197 if (sa->callp->sy_systrace_args_func != NULL) 198 /* 199 * Convert the syscall parameters using the registered 200 * function. 201 */ 202 (*sa->callp->sy_systrace_args_func)(sysnum, sa->args, 203 uargs, &n_args); 204 else 205 /* 206 * Use the built-in system call argument conversion 207 * function to translate the syscall structure fields 208 * into the array of 64-bit values that DTrace expects. 209 */ 210 systrace_args(sysnum, sa->args, uargs, &n_args); 211 /* 212 * Save probe arguments now so that we can retrieve them if 213 * the getargval method is called from further down the stack. 214 */ 215 curthread->t_dtrace_systrace_args = uargs; 216 } else { 217 if ((id = sa->callp->sy_return) == DTRACE_IDNONE) 218 return; 219 220 curthread->t_dtrace_systrace_args = NULL; 221 /* Set arg0 and arg1 as the return value of this syscall. */ 222 uargs[0] = uargs[1] = retval; 223 } 224 225 /* Process the probe using the converted argments. */ 226 dtrace_probe(id, uargs[0], uargs[1], uargs[2], uargs[3], uargs[4]); 227 } 228 #endif 229 230 static void 231 systrace_getargdesc(void *arg, dtrace_id_t id, void *parg, 232 dtrace_argdesc_t *desc) 233 { 234 int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg); 235 236 if (SYSTRACE_ISENTRY((uintptr_t)parg)) 237 systrace_entry_setargdesc(sysnum, desc->dtargd_ndx, 238 desc->dtargd_native, sizeof(desc->dtargd_native)); 239 else 240 systrace_return_setargdesc(sysnum, desc->dtargd_ndx, 241 desc->dtargd_native, sizeof(desc->dtargd_native)); 242 243 if (desc->dtargd_native[0] == '\0') 244 desc->dtargd_ndx = DTRACE_ARGNONE; 245 } 246 247 static uint64_t 248 systrace_getargval(void *arg __unused, dtrace_id_t id __unused, 249 void *parg __unused, int argno, int aframes __unused) 250 { 251 uint64_t *uargs; 252 253 uargs = curthread->t_dtrace_systrace_args; 254 if (uargs == NULL) 255 /* This is a return probe. */ 256 return (0); 257 if (argno >= nitems(((struct syscall_args *)NULL)->args)) 258 return (0); 259 return (uargs[argno]); 260 } 261 262 static void 263 systrace_provide(void *arg, dtrace_probedesc_t *desc) 264 { 265 int i; 266 267 if (desc != NULL) 268 return; 269 270 for (i = 0; i < MAXSYSCALL; i++) { 271 if (dtrace_probe_lookup(systrace_id, MODNAME, 272 uglyhack.pp_syscallnames[i], "entry") != 0) 273 continue; 274 275 (void)dtrace_probe_create(systrace_id, MODNAME, 276 uglyhack.pp_syscallnames[i], "entry", 277 SYSTRACE_ARTIFICIAL_FRAMES, 278 (void *)((uintptr_t)SYSTRACE_ENTRY(i))); 279 (void)dtrace_probe_create(systrace_id, MODNAME, 280 uglyhack.pp_syscallnames[i], "return", 281 SYSTRACE_ARTIFICIAL_FRAMES, 282 (void *)((uintptr_t)SYSTRACE_RETURN(i))); 283 } 284 } 285 286 static void 287 systrace_destroy(void *arg, dtrace_id_t id, void *parg) 288 { 289 #ifdef SYSTRACE_DEBUG 290 int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg); 291 292 /* 293 * There's nothing to do here but assert that we have actually been 294 * disabled. 295 */ 296 if (SYSTRACE_ISENTRY((uintptr_t)parg)) { 297 ASSERT(sysent[sysnum].sy_entry == DTRACE_IDNONE); 298 } else { 299 ASSERT(sysent[sysnum].sy_return == DTRACE_IDNONE); 300 } 301 #endif 302 } 303 304 static void 305 systrace_enable(void *arg, dtrace_id_t id, void *parg) 306 { 307 int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg); 308 309 SYSENT[sysnum].sy_systrace_args_func = systrace_args; 310 311 if (SYSTRACE_ISENTRY((uintptr_t)parg)) 312 SYSENT[sysnum].sy_entry = id; 313 else 314 SYSENT[sysnum].sy_return = id; 315 systrace_enabled_count++; 316 if (systrace_enabled_count == 1) 317 systrace_enabled = true; 318 } 319 320 static void 321 systrace_disable(void *arg, dtrace_id_t id, void *parg) 322 { 323 int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg); 324 325 SYSENT[sysnum].sy_systrace_args_func = NULL; 326 SYSENT[sysnum].sy_entry = DTRACE_IDNONE; 327 SYSENT[sysnum].sy_return = DTRACE_IDNONE; 328 systrace_enabled_count--; 329 if (systrace_enabled_count == 0) 330 systrace_enabled = false; 331 } 332 333 static void 334 systrace_load(void *dummy __unused) 335 { 336 337 if (dtrace_register(PROVNAME, &systrace_attr, DTRACE_PRIV_USER, NULL, 338 &systrace_pops, NULL, &systrace_id) != 0) 339 return; 340 341 #ifdef NATIVE_ABI 342 systrace_probe_func = systrace_probe; 343 #endif 344 } 345 346 static void 347 systrace_unload(void *dummy __unused) 348 { 349 350 #ifdef NATIVE_ABI 351 systrace_probe_func = NULL; 352 #endif 353 354 if (dtrace_unregister(systrace_id) != 0) 355 return; 356 } 357 358 static int 359 systrace_modevent(module_t mod __unused, int type, void *data __unused) 360 { 361 int error; 362 363 error = 0; 364 switch (type) { 365 case MOD_LOAD: 366 break; 367 368 case MOD_UNLOAD: 369 break; 370 371 case MOD_SHUTDOWN: 372 break; 373 374 default: 375 error = EOPNOTSUPP; 376 break; 377 378 } 379 return (error); 380 } 381 382 SYSINIT(systrace_load, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, 383 systrace_load, NULL); 384 SYSUNINIT(systrace_unload, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, 385 systrace_unload, NULL); 386 387 #ifdef LINUX_SYSTRACE 388 DEV_MODULE(systrace_linux, systrace_modevent, NULL); 389 MODULE_VERSION(systrace_linux, 1); 390 #ifdef __amd64__ 391 MODULE_DEPEND(systrace_linux, linux64, 1, 1, 1); 392 #else 393 MODULE_DEPEND(systrace_linux, linux, 1, 1, 1); 394 #endif 395 MODULE_DEPEND(systrace_linux, dtrace, 1, 1, 1); 396 MODULE_DEPEND(systrace_linux, opensolaris, 1, 1, 1); 397 #elif defined(LINUX32_SYSTRACE) 398 DEV_MODULE(systrace_linux32, systrace_modevent, NULL); 399 MODULE_VERSION(systrace_linux32, 1); 400 MODULE_DEPEND(systrace_linux32, linux, 1, 1, 1); 401 MODULE_DEPEND(systrace_linux32, dtrace, 1, 1, 1); 402 MODULE_DEPEND(systrace_linux32, opensolaris, 1, 1, 1); 403 #elif defined(FREEBSD32_SYSTRACE) 404 DEV_MODULE(systrace_freebsd32, systrace_modevent, NULL); 405 MODULE_VERSION(systrace_freebsd32, 1); 406 MODULE_DEPEND(systrace_freebsd32, dtrace, 1, 1, 1); 407 MODULE_DEPEND(systrace_freebsd32, opensolaris, 1, 1, 1); 408 #else 409 DEV_MODULE(systrace, systrace_modevent, NULL); 410 MODULE_VERSION(systrace, 1); 411 MODULE_DEPEND(systrace, dtrace, 1, 1, 1); 412 MODULE_DEPEND(systrace, opensolaris, 1, 1, 1); 413 #endif 414