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 */ 23 /* 24 * Copyright 2005 Sun Microsystems, Inc. All rights reserved. 25 * Use is subject to license terms. 26 */ 27 28 #include <sys/param.h> 29 #include <sys/systm.h> 30 #include <sys/kernel.h> 31 #include <sys/malloc.h> 32 #include <sys/kmem.h> 33 #include <sys/proc.h> 34 #include <sys/smp.h> 35 #include <sys/dtrace_impl.h> 36 #include <sys/dtrace_bsd.h> 37 #include <cddl/dev/dtrace/dtrace_cddl.h> 38 #include <machine/armreg.h> 39 #include <machine/clock.h> 40 #include <machine/frame.h> 41 #include <machine/trap.h> 42 #include <machine/vmparam.h> 43 #include <vm/pmap.h> 44 45 extern dtrace_id_t dtrace_probeid_error; 46 extern int (*dtrace_invop_jump_addr)(struct trapframe *); 47 extern void dtrace_getnanotime(struct timespec *tsp); 48 extern void dtrace_getnanouptime(struct timespec *tsp); 49 50 int dtrace_invop(uintptr_t, struct trapframe *, uintptr_t); 51 void dtrace_invop_init(void); 52 void dtrace_invop_uninit(void); 53 54 typedef struct dtrace_invop_hdlr { 55 int (*dtih_func)(uintptr_t, struct trapframe *, uintptr_t); 56 struct dtrace_invop_hdlr *dtih_next; 57 } dtrace_invop_hdlr_t; 58 59 dtrace_invop_hdlr_t *dtrace_invop_hdlr; 60 61 int 62 dtrace_invop(uintptr_t addr, struct trapframe *frame, uintptr_t eax) 63 { 64 struct thread *td; 65 dtrace_invop_hdlr_t *hdlr; 66 int rval; 67 68 rval = 0; 69 td = curthread; 70 td->t_dtrace_trapframe = frame; 71 for (hdlr = dtrace_invop_hdlr; hdlr != NULL; hdlr = hdlr->dtih_next) 72 if ((rval = hdlr->dtih_func(addr, frame, eax)) != 0) 73 break; 74 td->t_dtrace_trapframe = NULL; 75 return (rval); 76 } 77 78 void 79 dtrace_invop_add(int (*func)(uintptr_t, struct trapframe *, uintptr_t)) 80 { 81 dtrace_invop_hdlr_t *hdlr; 82 83 hdlr = kmem_alloc(sizeof (dtrace_invop_hdlr_t), KM_SLEEP); 84 hdlr->dtih_func = func; 85 hdlr->dtih_next = dtrace_invop_hdlr; 86 dtrace_invop_hdlr = hdlr; 87 } 88 89 void 90 dtrace_invop_remove(int (*func)(uintptr_t, struct trapframe *, uintptr_t)) 91 { 92 dtrace_invop_hdlr_t *hdlr, *prev; 93 94 hdlr = dtrace_invop_hdlr; 95 prev = NULL; 96 97 for (;;) { 98 if (hdlr == NULL) 99 panic("attempt to remove non-existent invop handler"); 100 101 if (hdlr->dtih_func == func) 102 break; 103 104 prev = hdlr; 105 hdlr = hdlr->dtih_next; 106 } 107 108 if (prev == NULL) { 109 ASSERT(dtrace_invop_hdlr == hdlr); 110 dtrace_invop_hdlr = hdlr->dtih_next; 111 } else { 112 ASSERT(dtrace_invop_hdlr != hdlr); 113 prev->dtih_next = hdlr->dtih_next; 114 } 115 116 kmem_free(hdlr, 0); 117 } 118 119 /*ARGSUSED*/ 120 void 121 dtrace_toxic_ranges(void (*func)(uintptr_t base, uintptr_t limit)) 122 { 123 124 (*func)(0, (uintptr_t)VM_MIN_KERNEL_ADDRESS); 125 } 126 127 void 128 dtrace_xcall(processorid_t cpu, dtrace_xcall_t func, void *arg) 129 { 130 cpuset_t cpus; 131 132 if (cpu == DTRACE_CPUALL) 133 cpus = all_cpus; 134 else 135 CPU_SETOF(cpu, &cpus); 136 137 smp_rendezvous_cpus(cpus, smp_no_rendezvous_barrier, func, 138 smp_no_rendezvous_barrier, arg); 139 } 140 141 static void 142 dtrace_sync_func(void) 143 { 144 145 } 146 147 void 148 dtrace_sync(void) 149 { 150 151 dtrace_xcall(DTRACE_CPUALL, (dtrace_xcall_t)dtrace_sync_func, NULL); 152 } 153 154 static uint64_t nsec_scale; 155 156 #define SCALE_SHIFT 25 157 158 /* 159 * Choose scaling factors which let us convert a cntvct_el0 value to nanoseconds 160 * without overflow, as in the amd64 implementation. 161 * 162 * Documentation for the ARM generic timer states that typical counter 163 * frequencies are in the range 1Mhz-50Mhz; in ARMv9 the frequency is fixed at 164 * 1GHz. The lower bound of 1MHz forces the shift to be at most 25 bits. At 165 * that frequency, the calculation (hi * scale) << (32 - shift) will not 166 * overflow for over 100 years, assuming that the counter value starts at 0 upon 167 * boot. 168 */ 169 static void 170 dtrace_gethrtime_init(void *arg __unused) 171 { 172 uint64_t freq; 173 174 freq = READ_SPECIALREG(cntfrq_el0); 175 nsec_scale = ((uint64_t)NANOSEC << SCALE_SHIFT) / freq; 176 } 177 SYSINIT(dtrace_gethrtime_init, SI_SUB_DTRACE, SI_ORDER_ANY, 178 dtrace_gethrtime_init, NULL); 179 180 /* 181 * DTrace needs a high resolution time function which can be called from a 182 * probe context and guaranteed not to have instrumented with probes itself. 183 * 184 * Returns nanoseconds since some arbitrary point in time (likely SoC reset?). 185 */ 186 uint64_t 187 dtrace_gethrtime(void) 188 { 189 uint64_t count, freq; 190 uint32_t lo, hi; 191 192 count = READ_SPECIALREG(cntvct_el0); 193 lo = count; 194 hi = count >> 32; 195 return (((lo * nsec_scale) >> SCALE_SHIFT) + 196 ((hi * nsec_scale) << (32 - SCALE_SHIFT))); 197 } 198 199 /* 200 * Return a much lower resolution wallclock time based on the system clock 201 * updated by the timer. If needed, we could add a version interpolated from 202 * the system clock as is the case with dtrace_gethrtime(). 203 */ 204 uint64_t 205 dtrace_gethrestime(void) 206 { 207 struct timespec current_time; 208 209 dtrace_getnanotime(¤t_time); 210 211 return (current_time.tv_sec * 1000000000UL + current_time.tv_nsec); 212 } 213 214 /* Function to handle DTrace traps during probes. See arm64/arm64/trap.c */ 215 int 216 dtrace_trap(struct trapframe *frame, u_int type) 217 { 218 /* 219 * A trap can occur while DTrace executes a probe. Before 220 * executing the probe, DTrace blocks re-scheduling and sets 221 * a flag in its per-cpu flags to indicate that it doesn't 222 * want to fault. On returning from the probe, the no-fault 223 * flag is cleared and finally re-scheduling is enabled. 224 * 225 * Check if DTrace has enabled 'no-fault' mode: 226 * 227 */ 228 229 if ((cpu_core[curcpu].cpuc_dtrace_flags & CPU_DTRACE_NOFAULT) != 0) { 230 /* 231 * There are only a couple of trap types that are expected. 232 * All the rest will be handled in the usual way. 233 */ 234 switch (type) { 235 case EXCP_DATA_ABORT: 236 /* Flag a bad address. */ 237 cpu_core[curcpu].cpuc_dtrace_flags |= CPU_DTRACE_BADADDR; 238 cpu_core[curcpu].cpuc_dtrace_illval = frame->tf_far; 239 240 /* 241 * Offset the instruction pointer to the instruction 242 * following the one causing the fault. 243 */ 244 frame->tf_elr += 4; 245 return (1); 246 default: 247 /* Handle all other traps in the usual way. */ 248 break; 249 } 250 } 251 252 /* Handle the trap in the usual way. */ 253 return (0); 254 } 255 256 void 257 dtrace_probe_error(dtrace_state_t *state, dtrace_epid_t epid, int which, 258 int fault, int fltoffs, uintptr_t illval) 259 { 260 261 dtrace_probe(dtrace_probeid_error, (uint64_t)(uintptr_t)state, 262 (uintptr_t)epid, 263 (uintptr_t)which, (uintptr_t)fault, (uintptr_t)fltoffs); 264 } 265 266 static void 267 dtrace_load64(uint64_t *addr, struct trapframe *frame, u_int reg) 268 { 269 270 KASSERT(reg <= 31, ("dtrace_load64: Invalid register %u", reg)); 271 if (reg < nitems(frame->tf_x)) 272 frame->tf_x[reg] = *addr; 273 else if (reg == 30) /* lr */ 274 frame->tf_lr = *addr; 275 /* Nothing to do for load to xzr */ 276 } 277 278 static void 279 dtrace_store64(uint64_t *addr, struct trapframe *frame, u_int reg) 280 { 281 282 KASSERT(reg <= 31, ("dtrace_store64: Invalid register %u", reg)); 283 if (reg < nitems(frame->tf_x)) 284 *addr = frame->tf_x[reg]; 285 else if (reg == 30) /* lr */ 286 *addr = frame->tf_lr; 287 else if (reg == 31) /* xzr */ 288 *addr = 0; 289 } 290 291 static int 292 dtrace_invop_start(struct trapframe *frame) 293 { 294 int data, invop, tmp; 295 296 invop = dtrace_invop(frame->tf_elr, frame, frame->tf_x[0]); 297 298 tmp = (invop & LDP_STP_MASK); 299 if (tmp == STP_64 || tmp == LDP_64) { 300 register_t arg1, arg2, *sp; 301 int offs; 302 303 sp = (register_t *)frame->tf_sp; 304 data = invop; 305 arg1 = (data >> ARG1_SHIFT) & ARG1_MASK; 306 arg2 = (data >> ARG2_SHIFT) & ARG2_MASK; 307 308 offs = (data >> OFFSET_SHIFT) & OFFSET_MASK; 309 310 switch (tmp) { 311 case STP_64: 312 if (offs >> (OFFSET_SIZE - 1)) 313 sp -= (~offs & OFFSET_MASK) + 1; 314 else 315 sp += (offs); 316 dtrace_store64(sp + 0, frame, arg1); 317 dtrace_store64(sp + 1, frame, arg2); 318 break; 319 case LDP_64: 320 dtrace_load64(sp + 0, frame, arg1); 321 dtrace_load64(sp + 1, frame, arg2); 322 if (offs >> (OFFSET_SIZE - 1)) 323 sp -= (~offs & OFFSET_MASK) + 1; 324 else 325 sp += (offs); 326 break; 327 default: 328 break; 329 } 330 331 /* Update the stack pointer and program counter to continue */ 332 frame->tf_sp = (register_t)sp; 333 frame->tf_elr += INSN_SIZE; 334 return (0); 335 } 336 337 if ((invop & SUB_MASK) == SUB_INSTR) { 338 frame->tf_sp -= (invop >> SUB_IMM_SHIFT) & SUB_IMM_MASK; 339 frame->tf_elr += INSN_SIZE; 340 return (0); 341 } 342 343 if (invop == NOP_INSTR) { 344 frame->tf_elr += INSN_SIZE; 345 return (0); 346 } 347 348 if ((invop & B_MASK) == B_INSTR) { 349 data = (invop & B_DATA_MASK); 350 /* The data is the number of 4-byte words to change the pc */ 351 data *= 4; 352 frame->tf_elr += data; 353 return (0); 354 } 355 356 if (invop == RET_INSTR) { 357 frame->tf_elr = frame->tf_lr; 358 return (0); 359 } 360 361 return (-1); 362 } 363 364 void 365 dtrace_invop_init(void) 366 { 367 368 dtrace_invop_jump_addr = dtrace_invop_start; 369 } 370 371 void 372 dtrace_invop_uninit(void) 373 { 374 375 dtrace_invop_jump_addr = 0; 376 } 377