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, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 * 22 * Portions Copyright 2016 Ruslan Bukin <br@bsdpad.com> 23 * 24 * $FreeBSD$ 25 */ 26 /* 27 * Copyright 2005 Sun Microsystems, Inc. All rights reserved. 28 * Use is subject to license terms. 29 */ 30 #include <sys/cdefs.h> 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/kernel.h> 35 #include <sys/stack.h> 36 #include <sys/pcpu.h> 37 38 #include <machine/frame.h> 39 #include <machine/md_var.h> 40 #include <machine/reg.h> 41 42 #include <vm/vm.h> 43 #include <vm/vm_param.h> 44 #include <vm/pmap.h> 45 46 #include <machine/atomic.h> 47 #include <machine/db_machdep.h> 48 #include <machine/md_var.h> 49 #include <machine/stack.h> 50 #include <ddb/db_sym.h> 51 #include <ddb/ddb.h> 52 #include <sys/kdb.h> 53 54 #include "regset.h" 55 56 /* 57 * Wee need some reasonable default to prevent backtrace code 58 * from wandering too far 59 */ 60 #define MAX_FUNCTION_SIZE 0x10000 61 #define MAX_PROLOGUE_SIZE 0x100 62 #define MAX_USTACK_DEPTH 2048 63 64 uint8_t dtrace_fuword8_nocheck(void *); 65 uint16_t dtrace_fuword16_nocheck(void *); 66 uint32_t dtrace_fuword32_nocheck(void *); 67 uint64_t dtrace_fuword64_nocheck(void *); 68 69 void 70 dtrace_getpcstack(pc_t *pcstack, int pcstack_limit, int aframes, 71 uint32_t *intrpc) 72 { 73 struct unwind_state state; 74 int scp_offset; 75 register_t sp; 76 int depth; 77 78 depth = 0; 79 80 if (intrpc != 0) { 81 pcstack[depth++] = (pc_t) intrpc; 82 } 83 84 aframes++; 85 86 __asm __volatile("mv %0, sp" : "=&r" (sp)); 87 88 state.fp = (uint64_t)__builtin_frame_address(0); 89 state.sp = sp; 90 state.pc = (uint64_t)dtrace_getpcstack; 91 92 while (depth < pcstack_limit) { 93 if (unwind_frame(&state)) 94 break; 95 96 if (!INKERNEL(state.pc) || !INKERNEL(state.fp)) 97 break; 98 99 /* 100 * NB: Unlike some other architectures, we don't need to 101 * explicitly insert cpu_dtrace_caller as it appears in the 102 * normal kernel stack trace rather than a special trap frame. 103 */ 104 if (aframes > 0) { 105 aframes--; 106 } else { 107 pcstack[depth++] = state.pc; 108 } 109 110 } 111 112 for (; depth < pcstack_limit; depth++) { 113 pcstack[depth] = 0; 114 } 115 } 116 117 static int 118 dtrace_getustack_common(uint64_t *pcstack, int pcstack_limit, uintptr_t pc, 119 uintptr_t fp) 120 { 121 volatile uint16_t *flags; 122 uintptr_t oldfp; 123 int ret; 124 125 ret = 0; 126 flags = (volatile uint16_t *)&cpu_core[curcpu].cpuc_dtrace_flags; 127 128 ASSERT(pcstack == NULL || pcstack_limit > 0); 129 130 while (pc != 0) { 131 /* 132 * We limit the number of times we can go around this 133 * loop to account for a circular stack. 134 */ 135 if (ret++ >= MAX_USTACK_DEPTH) { 136 *flags |= CPU_DTRACE_BADSTACK; 137 cpu_core[curcpu].cpuc_dtrace_illval = fp; 138 break; 139 } 140 141 if (pcstack != NULL) { 142 *pcstack++ = (uint64_t)pc; 143 pcstack_limit--; 144 if (pcstack_limit <= 0) 145 break; 146 } 147 148 if (fp == 0) 149 break; 150 151 pc = dtrace_fuword64((void *)(fp + 152 offsetof(struct riscv_frame, f_retaddr))); 153 fp = dtrace_fuword64((void *)fp); 154 155 if (fp == oldfp) { 156 *flags |= CPU_DTRACE_BADSTACK; 157 cpu_core[curcpu].cpuc_dtrace_illval = fp; 158 break; 159 } 160 } 161 162 return (ret); 163 } 164 165 void 166 dtrace_getupcstack(uint64_t *pcstack, int pcstack_limit) 167 { 168 volatile uint16_t *flags; 169 struct trapframe *tf; 170 uintptr_t pc, sp, fp; 171 proc_t *p; 172 int n; 173 174 p = curproc; 175 flags = (volatile uint16_t *)&cpu_core[curcpu].cpuc_dtrace_flags; 176 177 if (*flags & CPU_DTRACE_FAULT) 178 return; 179 180 if (pcstack_limit <= 0) 181 return; 182 183 /* 184 * If there's no user context we still need to zero the stack. 185 */ 186 if (p == NULL || (tf = curthread->td_frame) == NULL) 187 goto zero; 188 189 *pcstack++ = (uint64_t)p->p_pid; 190 pcstack_limit--; 191 192 if (pcstack_limit <= 0) 193 return; 194 195 pc = tf->tf_sepc; 196 sp = tf->tf_sp; 197 fp = tf->tf_s[0]; 198 199 if (DTRACE_CPUFLAG_ISSET(CPU_DTRACE_ENTRY)) { 200 /* 201 * In an entry probe. The frame pointer has not yet been 202 * pushed (that happens in the function prologue). The 203 * best approach is to add the current pc as a missing top 204 * of stack and back the pc up to the caller, which is stored 205 * at the current stack pointer address since the call 206 * instruction puts it there right before the branch. 207 */ 208 209 *pcstack++ = (uint64_t)pc; 210 pcstack_limit--; 211 if (pcstack_limit <= 0) 212 return; 213 214 pc = tf->tf_ra; 215 } 216 217 n = dtrace_getustack_common(pcstack, pcstack_limit, pc, fp); 218 ASSERT(n >= 0); 219 ASSERT(n <= pcstack_limit); 220 221 pcstack += n; 222 pcstack_limit -= n; 223 224 zero: 225 while (pcstack_limit-- > 0) 226 *pcstack++ = 0; 227 } 228 229 int 230 dtrace_getustackdepth(void) 231 { 232 233 printf("IMPLEMENT ME: %s\n", __func__); 234 235 return (0); 236 } 237 238 void 239 dtrace_getufpstack(uint64_t *pcstack, uint64_t *fpstack, int pcstack_limit) 240 { 241 242 printf("IMPLEMENT ME: %s\n", __func__); 243 } 244 245 /*ARGSUSED*/ 246 uint64_t 247 dtrace_getarg(int arg, int aframes) 248 { 249 250 printf("IMPLEMENT ME: %s\n", __func__); 251 252 return (0); 253 } 254 255 int 256 dtrace_getstackdepth(int aframes) 257 { 258 struct unwind_state state; 259 int scp_offset; 260 register_t sp; 261 int depth; 262 int done; 263 264 depth = 1; 265 done = 0; 266 267 __asm __volatile("mv %0, sp" : "=&r" (sp)); 268 269 state.fp = (uint64_t)__builtin_frame_address(0); 270 state.sp = sp; 271 state.pc = (uint64_t)dtrace_getstackdepth; 272 273 do { 274 done = unwind_frame(&state); 275 if (!INKERNEL(state.pc) || !INKERNEL(state.fp)) 276 break; 277 depth++; 278 } while (!done); 279 280 if (depth < aframes) 281 return (0); 282 else 283 return (depth - aframes); 284 } 285 286 ulong_t 287 dtrace_getreg(struct trapframe *rp, uint_t reg) 288 { 289 290 printf("IMPLEMENT ME: %s\n", __func__); 291 292 return (0); 293 } 294 295 static int 296 dtrace_copycheck(uintptr_t uaddr, uintptr_t kaddr, size_t size) 297 { 298 299 if (uaddr + size > VM_MAXUSER_ADDRESS || uaddr + size < uaddr) { 300 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR); 301 cpu_core[curcpu].cpuc_dtrace_illval = uaddr; 302 return (0); 303 } 304 305 return (1); 306 } 307 308 void 309 dtrace_copyin(uintptr_t uaddr, uintptr_t kaddr, size_t size, 310 volatile uint16_t *flags) 311 { 312 313 if (dtrace_copycheck(uaddr, kaddr, size)) 314 dtrace_copy(uaddr, kaddr, size); 315 } 316 317 void 318 dtrace_copyout(uintptr_t kaddr, uintptr_t uaddr, size_t size, 319 volatile uint16_t *flags) 320 { 321 322 if (dtrace_copycheck(uaddr, kaddr, size)) 323 dtrace_copy(kaddr, uaddr, size); 324 } 325 326 void 327 dtrace_copyinstr(uintptr_t uaddr, uintptr_t kaddr, size_t size, 328 volatile uint16_t *flags) 329 { 330 331 if (dtrace_copycheck(uaddr, kaddr, size)) 332 dtrace_copystr(uaddr, kaddr, size, flags); 333 } 334 335 void 336 dtrace_copyoutstr(uintptr_t kaddr, uintptr_t uaddr, size_t size, 337 volatile uint16_t *flags) 338 { 339 340 if (dtrace_copycheck(uaddr, kaddr, size)) 341 dtrace_copystr(kaddr, uaddr, size, flags); 342 } 343 344 uint8_t 345 dtrace_fuword8(void *uaddr) 346 { 347 348 if ((uintptr_t)uaddr > VM_MAXUSER_ADDRESS) { 349 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR); 350 cpu_core[curcpu].cpuc_dtrace_illval = (uintptr_t)uaddr; 351 return (0); 352 } 353 354 return (dtrace_fuword8_nocheck(uaddr)); 355 } 356 357 uint16_t 358 dtrace_fuword16(void *uaddr) 359 { 360 361 if ((uintptr_t)uaddr > VM_MAXUSER_ADDRESS) { 362 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR); 363 cpu_core[curcpu].cpuc_dtrace_illval = (uintptr_t)uaddr; 364 return (0); 365 } 366 367 return (dtrace_fuword16_nocheck(uaddr)); 368 } 369 370 uint32_t 371 dtrace_fuword32(void *uaddr) 372 { 373 374 if ((uintptr_t)uaddr > VM_MAXUSER_ADDRESS) { 375 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR); 376 cpu_core[curcpu].cpuc_dtrace_illval = (uintptr_t)uaddr; 377 return (0); 378 } 379 380 return (dtrace_fuword32_nocheck(uaddr)); 381 } 382 383 uint64_t 384 dtrace_fuword64(void *uaddr) 385 { 386 387 if ((uintptr_t)uaddr > VM_MAXUSER_ADDRESS) { 388 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR); 389 cpu_core[curcpu].cpuc_dtrace_illval = (uintptr_t)uaddr; 390 return (0); 391 } 392 393 return (dtrace_fuword64_nocheck(uaddr)); 394 } 395