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