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/sysent.h> 51 #include <sys/sysproto.h> 52 #include <sys/uio.h> 53 #include <sys/unistd.h> 54 55 #include <cddl/dev/dtrace/dtrace_cddl.h> 56 57 #include <machine/stdarg.h> 58 59 #ifdef LINUX_SYSTRACE 60 #if defined(__amd64__) 61 #include <amd64/linux/linux.h> 62 #include <amd64/linux/linux_proto.h> 63 #include <amd64/linux/linux_syscalls.c> 64 #include <amd64/linux/linux_systrace_args.c> 65 #elif defined(__i386__) 66 #include <i386/linux/linux.h> 67 #include <i386/linux/linux_proto.h> 68 #include <i386/linux/linux_syscalls.c> 69 #include <i386/linux/linux_systrace_args.c> 70 #else 71 #error Only i386 and amd64 are supported. 72 #endif 73 #define MODNAME "linux" 74 extern struct sysent linux_sysent[]; 75 #define MAXSYSCALL LINUX_SYS_MAXSYSCALL 76 #define SYSCALLNAMES linux_syscallnames 77 #define SYSENT linux_sysent 78 #elif defined(LINUX32_SYSTRACE) 79 #if defined(__amd64__) 80 #include <amd64/linux32/linux.h> 81 #include <amd64/linux32/linux32_proto.h> 82 #include <amd64/linux32/linux32_syscalls.c> 83 #include <amd64/linux32/linux32_systrace_args.c> 84 #else 85 #error Only amd64 is supported. 86 #endif 87 #define MODNAME "linux32" 88 extern struct sysent linux32_sysent[]; 89 #define MAXSYSCALL LINUX32_SYS_MAXSYSCALL 90 #define SYSCALLNAMES linux32_syscallnames 91 #define SYSENT linux32_sysent 92 #elif defined(FREEBSD32_SYSTRACE) 93 /* 94 * The syscall arguments are processed into a DTrace argument array 95 * using a generated function. See sys/tools/makesyscalls.lua. 96 */ 97 #include <compat/freebsd32/freebsd32_proto.h> 98 #include <compat/freebsd32/freebsd32_util.h> 99 #include <compat/freebsd32/freebsd32_syscall.h> 100 #include <compat/freebsd32/freebsd32_systrace_args.c> 101 extern const char *freebsd32_syscallnames[]; 102 #define MODNAME "freebsd32" 103 #define MAXSYSCALL FREEBSD32_SYS_MAXSYSCALL 104 #define SYSCALLNAMES freebsd32_syscallnames 105 #define SYSENT freebsd32_sysent 106 #else 107 /* 108 * The syscall arguments are processed into a DTrace argument array 109 * using a generated function. See sys/tools/makesyscalls.lua. 110 */ 111 #include <sys/syscall.h> 112 #include <kern/systrace_args.c> 113 #define MODNAME "freebsd" 114 #define MAXSYSCALL SYS_MAXSYSCALL 115 #define SYSCALLNAMES syscallnames 116 #define SYSENT sysent 117 #define NATIVE_ABI 118 #endif 119 120 #define PROVNAME "syscall" 121 #define DEVNAME "dtrace/systrace/" MODNAME 122 123 #define SYSTRACE_ARTIFICIAL_FRAMES 1 124 125 #define SYSTRACE_SHIFT 16 126 #define SYSTRACE_ISENTRY(x) ((int)(x) >> SYSTRACE_SHIFT) 127 #define SYSTRACE_SYSNUM(x) ((int)(x) & ((1 << SYSTRACE_SHIFT) - 1)) 128 #define SYSTRACE_ENTRY(id) ((1 << SYSTRACE_SHIFT) | (id)) 129 #define SYSTRACE_RETURN(id) (id) 130 131 #if ((1 << SYSTRACE_SHIFT) <= MAXSYSCALL) 132 #error 1 << SYSTRACE_SHIFT must exceed number of system calls 133 #endif 134 135 static int systrace_enabled_count; 136 137 static void systrace_load(void *); 138 static void systrace_unload(void *); 139 140 static void systrace_getargdesc(void *, dtrace_id_t, void *, 141 dtrace_argdesc_t *); 142 static uint64_t systrace_getargval(void *, dtrace_id_t, void *, int, int); 143 static void systrace_provide(void *, dtrace_probedesc_t *); 144 static void systrace_destroy(void *, dtrace_id_t, void *); 145 static void systrace_enable(void *, dtrace_id_t, void *); 146 static void systrace_disable(void *, dtrace_id_t, void *); 147 148 static union { 149 const char **p_constnames; 150 char **pp_syscallnames; 151 } uglyhack = { SYSCALLNAMES }; 152 153 static dtrace_pattr_t systrace_attr = { 154 { DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON }, 155 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN }, 156 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_ISA }, 157 { DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON }, 158 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_ISA }, 159 }; 160 161 static dtrace_pops_t systrace_pops = { 162 .dtps_provide = systrace_provide, 163 .dtps_provide_module = NULL, 164 .dtps_enable = systrace_enable, 165 .dtps_disable = systrace_disable, 166 .dtps_suspend = NULL, 167 .dtps_resume = NULL, 168 .dtps_getargdesc = systrace_getargdesc, 169 .dtps_getargval = systrace_getargval, 170 .dtps_usermode = NULL, 171 .dtps_destroy = systrace_destroy 172 }; 173 174 static dtrace_provider_id_t systrace_id; 175 176 #ifdef NATIVE_ABI 177 /* 178 * Probe callback function. 179 * 180 * Note: This function is called for _all_ syscalls, regardless of which sysent 181 * array the syscall comes from. It could be a standard syscall or a 182 * compat syscall from something like Linux. 183 */ 184 static void 185 systrace_probe(struct syscall_args *sa, enum systrace_probe_t type, int retval) 186 { 187 uint64_t uargs[nitems(sa->args)]; 188 dtrace_id_t id; 189 int n_args, sysnum; 190 191 sysnum = sa->code; 192 memset(uargs, 0, sizeof(uargs)); 193 194 if (type == SYSTRACE_ENTRY) { 195 if ((id = sa->callp->sy_entry) == DTRACE_IDNONE) 196 return; 197 198 if (sa->callp->sy_systrace_args_func != NULL) 199 /* 200 * Convert the syscall parameters using the registered 201 * function. 202 */ 203 (*sa->callp->sy_systrace_args_func)(sysnum, sa->args, 204 uargs, &n_args); 205 else 206 /* 207 * Use the built-in system call argument conversion 208 * function to translate the syscall structure fields 209 * into the array of 64-bit values that DTrace expects. 210 */ 211 systrace_args(sysnum, sa->args, uargs, &n_args); 212 /* 213 * Save probe arguments now so that we can retrieve them if 214 * the getargval method is called from further down the stack. 215 */ 216 curthread->t_dtrace_systrace_args = uargs; 217 } else { 218 if ((id = sa->callp->sy_return) == DTRACE_IDNONE) 219 return; 220 221 curthread->t_dtrace_systrace_args = NULL; 222 /* Set arg0 and arg1 as the return value of this syscall. */ 223 uargs[0] = uargs[1] = retval; 224 } 225 226 /* Process the probe using the converted argments. */ 227 dtrace_probe(id, uargs[0], uargs[1], uargs[2], uargs[3], uargs[4]); 228 } 229 #endif 230 231 static void 232 systrace_getargdesc(void *arg, dtrace_id_t id, void *parg, 233 dtrace_argdesc_t *desc) 234 { 235 int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg); 236 237 if (SYSTRACE_ISENTRY((uintptr_t)parg)) 238 systrace_entry_setargdesc(sysnum, desc->dtargd_ndx, 239 desc->dtargd_native, sizeof(desc->dtargd_native)); 240 else 241 systrace_return_setargdesc(sysnum, desc->dtargd_ndx, 242 desc->dtargd_native, sizeof(desc->dtargd_native)); 243 244 if (desc->dtargd_native[0] == '\0') 245 desc->dtargd_ndx = DTRACE_ARGNONE; 246 } 247 248 static uint64_t 249 systrace_getargval(void *arg __unused, dtrace_id_t id __unused, 250 void *parg __unused, int argno, int aframes __unused) 251 { 252 uint64_t *uargs; 253 254 uargs = curthread->t_dtrace_systrace_args; 255 if (uargs == NULL) 256 /* This is a return probe. */ 257 return (0); 258 if (argno >= nitems(((struct syscall_args *)NULL)->args)) 259 return (0); 260 return (uargs[argno]); 261 } 262 263 static void 264 systrace_provide(void *arg, dtrace_probedesc_t *desc) 265 { 266 int i; 267 268 if (desc != NULL) 269 return; 270 271 for (i = 0; i < MAXSYSCALL; i++) { 272 if (dtrace_probe_lookup(systrace_id, MODNAME, 273 uglyhack.pp_syscallnames[i], "entry") != 0) 274 continue; 275 276 (void)dtrace_probe_create(systrace_id, MODNAME, 277 uglyhack.pp_syscallnames[i], "entry", 278 SYSTRACE_ARTIFICIAL_FRAMES, 279 (void *)((uintptr_t)SYSTRACE_ENTRY(i))); 280 (void)dtrace_probe_create(systrace_id, MODNAME, 281 uglyhack.pp_syscallnames[i], "return", 282 SYSTRACE_ARTIFICIAL_FRAMES, 283 (void *)((uintptr_t)SYSTRACE_RETURN(i))); 284 } 285 } 286 287 static void 288 systrace_destroy(void *arg, dtrace_id_t id, void *parg) 289 { 290 #ifdef SYSTRACE_DEBUG 291 int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg); 292 293 /* 294 * There's nothing to do here but assert that we have actually been 295 * disabled. 296 */ 297 if (SYSTRACE_ISENTRY((uintptr_t)parg)) { 298 ASSERT(sysent[sysnum].sy_entry == DTRACE_IDNONE); 299 } else { 300 ASSERT(sysent[sysnum].sy_return == DTRACE_IDNONE); 301 } 302 #endif 303 } 304 305 static void 306 systrace_enable(void *arg, dtrace_id_t id, void *parg) 307 { 308 int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg); 309 310 SYSENT[sysnum].sy_systrace_args_func = systrace_args; 311 312 if (SYSTRACE_ISENTRY((uintptr_t)parg)) 313 SYSENT[sysnum].sy_entry = id; 314 else 315 SYSENT[sysnum].sy_return = id; 316 systrace_enabled_count++; 317 if (systrace_enabled_count == 1) 318 systrace_enabled = true; 319 } 320 321 static void 322 systrace_disable(void *arg, dtrace_id_t id, void *parg) 323 { 324 int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg); 325 326 SYSENT[sysnum].sy_systrace_args_func = NULL; 327 SYSENT[sysnum].sy_entry = DTRACE_IDNONE; 328 SYSENT[sysnum].sy_return = DTRACE_IDNONE; 329 systrace_enabled_count--; 330 if (systrace_enabled_count == 0) 331 systrace_enabled = false; 332 } 333 334 static void 335 systrace_load(void *dummy __unused) 336 { 337 338 if (dtrace_register(PROVNAME, &systrace_attr, DTRACE_PRIV_USER, NULL, 339 &systrace_pops, NULL, &systrace_id) != 0) 340 return; 341 342 #ifdef NATIVE_ABI 343 systrace_probe_func = systrace_probe; 344 #endif 345 } 346 347 static void 348 systrace_unload(void *dummy __unused) 349 { 350 351 #ifdef NATIVE_ABI 352 systrace_probe_func = NULL; 353 #endif 354 355 if (dtrace_unregister(systrace_id) != 0) 356 return; 357 } 358 359 static int 360 systrace_modevent(module_t mod __unused, int type, void *data __unused) 361 { 362 int error; 363 364 error = 0; 365 switch (type) { 366 case MOD_LOAD: 367 break; 368 369 case MOD_UNLOAD: 370 break; 371 372 case MOD_SHUTDOWN: 373 break; 374 375 default: 376 error = EOPNOTSUPP; 377 break; 378 379 } 380 return (error); 381 } 382 383 SYSINIT(systrace_load, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, 384 systrace_load, NULL); 385 SYSUNINIT(systrace_unload, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, 386 systrace_unload, NULL); 387 388 #ifdef LINUX_SYSTRACE 389 DEV_MODULE(systrace_linux, systrace_modevent, NULL); 390 MODULE_VERSION(systrace_linux, 1); 391 #ifdef __amd64__ 392 MODULE_DEPEND(systrace_linux, linux64, 1, 1, 1); 393 #else 394 MODULE_DEPEND(systrace_linux, linux, 1, 1, 1); 395 #endif 396 MODULE_DEPEND(systrace_linux, dtrace, 1, 1, 1); 397 MODULE_DEPEND(systrace_linux, opensolaris, 1, 1, 1); 398 #elif defined(LINUX32_SYSTRACE) 399 DEV_MODULE(systrace_linux32, systrace_modevent, NULL); 400 MODULE_VERSION(systrace_linux32, 1); 401 MODULE_DEPEND(systrace_linux32, linux, 1, 1, 1); 402 MODULE_DEPEND(systrace_linux32, dtrace, 1, 1, 1); 403 MODULE_DEPEND(systrace_linux32, opensolaris, 1, 1, 1); 404 #elif defined(FREEBSD32_SYSTRACE) 405 DEV_MODULE(systrace_freebsd32, systrace_modevent, NULL); 406 MODULE_VERSION(systrace_freebsd32, 1); 407 MODULE_DEPEND(systrace_freebsd32, dtrace, 1, 1, 1); 408 MODULE_DEPEND(systrace_freebsd32, opensolaris, 1, 1, 1); 409 #else 410 DEV_MODULE(systrace, systrace_modevent, NULL); 411 MODULE_VERSION(systrace, 1); 412 MODULE_DEPEND(systrace, dtrace, 1, 1, 1); 413 MODULE_DEPEND(systrace, opensolaris, 1, 1, 1); 414 #endif 415