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 * $FreeBSD$ 23 * 24 */ 25 /* 26 * Copyright 2005 Sun Microsystems, Inc. All rights reserved. 27 * Use is subject to license terms. 28 */ 29 30 #include <sys/param.h> 31 #include <sys/systm.h> 32 #include <sys/kernel.h> 33 #include <sys/malloc.h> 34 #include <sys/kmem.h> 35 #include <sys/proc.h> 36 #include <sys/smp.h> 37 #include <sys/dtrace_impl.h> 38 #include <sys/dtrace_bsd.h> 39 #include <cddl/dev/dtrace/dtrace_cddl.h> 40 #include <machine/armreg.h> 41 #include <machine/clock.h> 42 #include <machine/frame.h> 43 #include <machine/trap.h> 44 #include <machine/vmparam.h> 45 #include <vm/pmap.h> 46 47 extern dtrace_id_t dtrace_probeid_error; 48 extern int (*dtrace_invop_jump_addr)(struct trapframe *); 49 extern void dtrace_getnanotime(struct timespec *tsp); 50 extern void dtrace_getnanouptime(struct timespec *tsp); 51 52 int dtrace_invop(uintptr_t, struct trapframe *, uintptr_t); 53 void dtrace_invop_init(void); 54 void dtrace_invop_uninit(void); 55 56 typedef struct dtrace_invop_hdlr { 57 int (*dtih_func)(uintptr_t, struct trapframe *, uintptr_t); 58 struct dtrace_invop_hdlr *dtih_next; 59 } dtrace_invop_hdlr_t; 60 61 dtrace_invop_hdlr_t *dtrace_invop_hdlr; 62 63 int 64 dtrace_invop(uintptr_t addr, struct trapframe *frame, uintptr_t eax) 65 { 66 struct thread *td; 67 dtrace_invop_hdlr_t *hdlr; 68 int rval; 69 70 rval = 0; 71 td = curthread; 72 td->t_dtrace_trapframe = frame; 73 for (hdlr = dtrace_invop_hdlr; hdlr != NULL; hdlr = hdlr->dtih_next) 74 if ((rval = hdlr->dtih_func(addr, frame, eax)) != 0) 75 break; 76 td->t_dtrace_trapframe = NULL; 77 return (rval); 78 } 79 80 void 81 dtrace_invop_add(int (*func)(uintptr_t, struct trapframe *, uintptr_t)) 82 { 83 dtrace_invop_hdlr_t *hdlr; 84 85 hdlr = kmem_alloc(sizeof (dtrace_invop_hdlr_t), KM_SLEEP); 86 hdlr->dtih_func = func; 87 hdlr->dtih_next = dtrace_invop_hdlr; 88 dtrace_invop_hdlr = hdlr; 89 } 90 91 void 92 dtrace_invop_remove(int (*func)(uintptr_t, struct trapframe *, uintptr_t)) 93 { 94 dtrace_invop_hdlr_t *hdlr, *prev; 95 96 hdlr = dtrace_invop_hdlr; 97 prev = NULL; 98 99 for (;;) { 100 if (hdlr == NULL) 101 panic("attempt to remove non-existent invop handler"); 102 103 if (hdlr->dtih_func == func) 104 break; 105 106 prev = hdlr; 107 hdlr = hdlr->dtih_next; 108 } 109 110 if (prev == NULL) { 111 ASSERT(dtrace_invop_hdlr == hdlr); 112 dtrace_invop_hdlr = hdlr->dtih_next; 113 } else { 114 ASSERT(dtrace_invop_hdlr != hdlr); 115 prev->dtih_next = hdlr->dtih_next; 116 } 117 118 kmem_free(hdlr, 0); 119 } 120 121 /*ARGSUSED*/ 122 void 123 dtrace_toxic_ranges(void (*func)(uintptr_t base, uintptr_t limit)) 124 { 125 126 (*func)(0, (uintptr_t)VM_MIN_KERNEL_ADDRESS); 127 } 128 129 void 130 dtrace_xcall(processorid_t cpu, dtrace_xcall_t func, void *arg) 131 { 132 cpuset_t cpus; 133 134 if (cpu == DTRACE_CPUALL) 135 cpus = all_cpus; 136 else 137 CPU_SETOF(cpu, &cpus); 138 139 smp_rendezvous_cpus(cpus, smp_no_rendezvous_barrier, func, 140 smp_no_rendezvous_barrier, arg); 141 } 142 143 static void 144 dtrace_sync_func(void) 145 { 146 147 } 148 149 void 150 dtrace_sync(void) 151 { 152 153 dtrace_xcall(DTRACE_CPUALL, (dtrace_xcall_t)dtrace_sync_func, NULL); 154 } 155 156 /* 157 * DTrace needs a high resolution time function which can be called from a 158 * probe context and guaranteed not to have instrumented with probes itself. 159 * 160 * Returns nanoseconds since some arbitrary point in time (likely SoC reset?). 161 */ 162 uint64_t 163 dtrace_gethrtime(void) 164 { 165 uint64_t count, freq; 166 167 count = READ_SPECIALREG(cntvct_el0); 168 freq = READ_SPECIALREG(cntfrq_el0); 169 return ((1000000000UL * count) / freq); 170 } 171 172 /* 173 * Return a much lower resolution wallclock time based on the system clock 174 * updated by the timer. If needed, we could add a version interpolated from 175 * the system clock as is the case with dtrace_gethrtime(). 176 */ 177 uint64_t 178 dtrace_gethrestime(void) 179 { 180 struct timespec current_time; 181 182 dtrace_getnanotime(¤t_time); 183 184 return (current_time.tv_sec * 1000000000UL + current_time.tv_nsec); 185 } 186 187 /* Function to handle DTrace traps during probes. See arm64/arm64/trap.c */ 188 int 189 dtrace_trap(struct trapframe *frame, u_int type) 190 { 191 /* 192 * A trap can occur while DTrace executes a probe. Before 193 * executing the probe, DTrace blocks re-scheduling and sets 194 * a flag in its per-cpu flags to indicate that it doesn't 195 * want to fault. On returning from the probe, the no-fault 196 * flag is cleared and finally re-scheduling is enabled. 197 * 198 * Check if DTrace has enabled 'no-fault' mode: 199 * 200 */ 201 202 if ((cpu_core[curcpu].cpuc_dtrace_flags & CPU_DTRACE_NOFAULT) != 0) { 203 /* 204 * There are only a couple of trap types that are expected. 205 * All the rest will be handled in the usual way. 206 */ 207 switch (type) { 208 case EXCP_DATA_ABORT: 209 /* Flag a bad address. */ 210 cpu_core[curcpu].cpuc_dtrace_flags |= CPU_DTRACE_BADADDR; 211 cpu_core[curcpu].cpuc_dtrace_illval = frame->tf_far; 212 213 /* 214 * Offset the instruction pointer to the instruction 215 * following the one causing the fault. 216 */ 217 frame->tf_elr += 4; 218 return (1); 219 default: 220 /* Handle all other traps in the usual way. */ 221 break; 222 } 223 } 224 225 /* Handle the trap in the usual way. */ 226 return (0); 227 } 228 229 void 230 dtrace_probe_error(dtrace_state_t *state, dtrace_epid_t epid, int which, 231 int fault, int fltoffs, uintptr_t illval) 232 { 233 234 dtrace_probe(dtrace_probeid_error, (uint64_t)(uintptr_t)state, 235 (uintptr_t)epid, 236 (uintptr_t)which, (uintptr_t)fault, (uintptr_t)fltoffs); 237 } 238 239 static void 240 dtrace_load64(uint64_t *addr, struct trapframe *frame, u_int reg) 241 { 242 243 KASSERT(reg <= 31, ("dtrace_load64: Invalid register %u", reg)); 244 if (reg < nitems(frame->tf_x)) 245 frame->tf_x[reg] = *addr; 246 else if (reg == 30) /* lr */ 247 frame->tf_lr = *addr; 248 /* Nothing to do for load to xzr */ 249 } 250 251 static void 252 dtrace_store64(uint64_t *addr, struct trapframe *frame, u_int reg) 253 { 254 255 KASSERT(reg <= 31, ("dtrace_store64: Invalid register %u", reg)); 256 if (reg < nitems(frame->tf_x)) 257 *addr = frame->tf_x[reg]; 258 else if (reg == 30) /* lr */ 259 *addr = frame->tf_lr; 260 else if (reg == 31) /* xzr */ 261 *addr = 0; 262 } 263 264 static int 265 dtrace_invop_start(struct trapframe *frame) 266 { 267 int data, invop, reg, update_sp; 268 register_t arg1, arg2; 269 register_t *sp; 270 int offs; 271 int tmp; 272 int i; 273 274 invop = dtrace_invop(frame->tf_elr, frame, frame->tf_x[0]); 275 276 tmp = (invop & LDP_STP_MASK); 277 if (tmp == STP_64 || tmp == LDP_64) { 278 sp = (register_t *)frame->tf_sp; 279 data = invop; 280 arg1 = (data >> ARG1_SHIFT) & ARG1_MASK; 281 arg2 = (data >> ARG2_SHIFT) & ARG2_MASK; 282 283 offs = (data >> OFFSET_SHIFT) & OFFSET_MASK; 284 285 switch (tmp) { 286 case STP_64: 287 if (offs >> (OFFSET_SIZE - 1)) 288 sp -= (~offs & OFFSET_MASK) + 1; 289 else 290 sp += (offs); 291 dtrace_store64(sp + 0, frame, arg1); 292 dtrace_store64(sp + 1, frame, arg2); 293 break; 294 case LDP_64: 295 dtrace_load64(sp + 0, frame, arg1); 296 dtrace_load64(sp + 1, frame, arg2); 297 if (offs >> (OFFSET_SIZE - 1)) 298 sp -= (~offs & OFFSET_MASK) + 1; 299 else 300 sp += (offs); 301 break; 302 default: 303 break; 304 } 305 306 /* Update the stack pointer and program counter to continue */ 307 frame->tf_sp = (register_t)sp; 308 frame->tf_elr += INSN_SIZE; 309 return (0); 310 } 311 312 if ((invop & SUB_MASK) == SUB_INSTR) { 313 frame->tf_sp -= (invop >> SUB_IMM_SHIFT) & SUB_IMM_MASK; 314 frame->tf_elr += INSN_SIZE; 315 return (0); 316 } 317 318 if (invop == NOP_INSTR) { 319 frame->tf_elr += INSN_SIZE; 320 return (0); 321 } 322 323 if ((invop & B_MASK) == B_INSTR) { 324 data = (invop & B_DATA_MASK); 325 /* The data is the number of 4-byte words to change the pc */ 326 data *= 4; 327 frame->tf_elr += data; 328 return (0); 329 } 330 331 if (invop == RET_INSTR) { 332 frame->tf_elr = frame->tf_lr; 333 return (0); 334 } 335 336 return (-1); 337 } 338 339 void 340 dtrace_invop_init(void) 341 { 342 343 dtrace_invop_jump_addr = dtrace_invop_start; 344 } 345 346 void 347 dtrace_invop_uninit(void) 348 { 349 350 dtrace_invop_jump_addr = 0; 351 } 352