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 <vm/pmap.h> 47 48 #define DELAYBRANCH(x) ((int)(x) < 0) 49 50 #define BIT_PC 15 51 #define BIT_LR 14 52 #define BIT_SP 13 53 54 extern dtrace_id_t dtrace_probeid_error; 55 extern int (*dtrace_invop_jump_addr)(struct trapframe *); 56 extern void dtrace_getnanotime(struct timespec *tsp); 57 extern void dtrace_getnanouptime(struct timespec *tsp); 58 59 int dtrace_invop(uintptr_t, struct trapframe *, uintptr_t); 60 void dtrace_invop_init(void); 61 void dtrace_invop_uninit(void); 62 63 typedef struct dtrace_invop_hdlr { 64 int (*dtih_func)(uintptr_t, struct trapframe *, uintptr_t); 65 struct dtrace_invop_hdlr *dtih_next; 66 } dtrace_invop_hdlr_t; 67 68 dtrace_invop_hdlr_t *dtrace_invop_hdlr; 69 70 int 71 dtrace_invop(uintptr_t addr, struct trapframe *frame, uintptr_t eax) 72 { 73 dtrace_invop_hdlr_t *hdlr; 74 int rval; 75 76 for (hdlr = dtrace_invop_hdlr; hdlr != NULL; hdlr = hdlr->dtih_next) 77 if ((rval = hdlr->dtih_func(addr, frame, eax)) != 0) 78 return (rval); 79 80 return (0); 81 } 82 83 84 void 85 dtrace_invop_add(int (*func)(uintptr_t, struct trapframe *, uintptr_t)) 86 { 87 dtrace_invop_hdlr_t *hdlr; 88 89 hdlr = kmem_alloc(sizeof (dtrace_invop_hdlr_t), KM_SLEEP); 90 hdlr->dtih_func = func; 91 hdlr->dtih_next = dtrace_invop_hdlr; 92 dtrace_invop_hdlr = hdlr; 93 } 94 95 void 96 dtrace_invop_remove(int (*func)(uintptr_t, struct trapframe *, uintptr_t)) 97 { 98 dtrace_invop_hdlr_t *hdlr = dtrace_invop_hdlr, *prev = NULL; 99 100 for (;;) { 101 if (hdlr == NULL) 102 panic("attempt to remove non-existent invop handler"); 103 104 if (hdlr->dtih_func == func) 105 break; 106 107 prev = hdlr; 108 hdlr = hdlr->dtih_next; 109 } 110 111 if (prev == NULL) { 112 ASSERT(dtrace_invop_hdlr == hdlr); 113 dtrace_invop_hdlr = hdlr->dtih_next; 114 } else { 115 ASSERT(dtrace_invop_hdlr != hdlr); 116 prev->dtih_next = hdlr->dtih_next; 117 } 118 119 kmem_free(hdlr, 0); 120 } 121 122 123 /*ARGSUSED*/ 124 void 125 dtrace_toxic_ranges(void (*func)(uintptr_t base, uintptr_t limit)) 126 { 127 128 /* 129 * There are no ranges to exclude that are common to all 32-bit arm 130 * platforms. This function only needs to exclude ranges "... in 131 * which it is impossible to recover from such a load after it has been 132 * attempted." -- i.e., accessing within the range causes some sort 133 * fault in the system which is not handled by the normal arm 134 * exception-handling mechanisms. If systems exist where that is the 135 * case, a method to handle this functionality would have to be added to 136 * the platform_if interface so that those systems could provide their 137 * specific toxic range(s). 138 */ 139 } 140 141 void 142 dtrace_xcall(processorid_t cpu, dtrace_xcall_t func, void *arg) 143 { 144 cpuset_t cpus; 145 146 if (cpu == DTRACE_CPUALL) 147 cpus = all_cpus; 148 else 149 CPU_SETOF(cpu, &cpus); 150 151 smp_rendezvous_cpus(cpus, smp_no_rendezvous_barrier, func, 152 smp_no_rendezvous_barrier, arg); 153 } 154 155 static void 156 dtrace_sync_func(void) 157 { 158 } 159 160 void 161 dtrace_sync(void) 162 { 163 dtrace_xcall(DTRACE_CPUALL, (dtrace_xcall_t)dtrace_sync_func, NULL); 164 } 165 166 /* 167 * DTrace needs a high resolution time function which can 168 * be called from a probe context and guaranteed not to have 169 * instrumented with probes itself. 170 * 171 * Returns nanoseconds since boot. 172 */ 173 uint64_t 174 dtrace_gethrtime() 175 { 176 struct timespec curtime; 177 178 dtrace_getnanouptime(&curtime); 179 180 return (curtime.tv_sec * 1000000000UL + curtime.tv_nsec); 181 182 } 183 184 uint64_t 185 dtrace_gethrestime(void) 186 { 187 struct timespec current_time; 188 189 dtrace_getnanotime(¤t_time); 190 191 return (current_time.tv_sec * 1000000000UL + current_time.tv_nsec); 192 } 193 194 /* Function to handle DTrace traps during probes. See amd64/amd64/trap.c */ 195 int 196 dtrace_trap(struct trapframe *frame, u_int type) 197 { 198 /* 199 * A trap can occur while DTrace executes a probe. Before 200 * executing the probe, DTrace blocks re-scheduling and sets 201 * a flag in its per-cpu flags to indicate that it doesn't 202 * want to fault. On returning from the probe, the no-fault 203 * flag is cleared and finally re-scheduling is enabled. 204 * 205 * Check if DTrace has enabled 'no-fault' mode: 206 * 207 */ 208 if ((cpu_core[curcpu].cpuc_dtrace_flags & CPU_DTRACE_NOFAULT) != 0) { 209 /* 210 * There are only a couple of trap types that are expected. 211 * All the rest will be handled in the usual way. 212 */ 213 switch (type) { 214 /* Page fault. */ 215 case FAULT_ALIGN: 216 /* Flag a bad address. */ 217 cpu_core[curcpu].cpuc_dtrace_flags |= CPU_DTRACE_BADADDR; 218 cpu_core[curcpu].cpuc_dtrace_illval = 0; 219 220 /* 221 * Offset the instruction pointer to the instruction 222 * following the one causing the fault. 223 */ 224 frame->tf_pc += sizeof(int); 225 return (1); 226 default: 227 /* Handle all other traps in the usual way. */ 228 break; 229 } 230 } 231 232 /* Handle the trap in the usual way. */ 233 return (0); 234 } 235 236 void 237 dtrace_probe_error(dtrace_state_t *state, dtrace_epid_t epid, int which, 238 int fault, int fltoffs, uintptr_t illval) 239 { 240 241 dtrace_probe(dtrace_probeid_error, (uint64_t)(uintptr_t)state, 242 (uintptr_t)epid, 243 (uintptr_t)which, (uintptr_t)fault, (uintptr_t)fltoffs); 244 } 245 246 static int 247 dtrace_invop_start(struct trapframe *frame) 248 { 249 register_t *r0, *sp; 250 int data, invop, reg, update_sp; 251 252 invop = dtrace_invop(frame->tf_pc, frame, frame->tf_r0); 253 switch (invop & DTRACE_INVOP_MASK) { 254 case DTRACE_INVOP_PUSHM: 255 sp = (register_t *)frame->tf_svc_sp; 256 r0 = &frame->tf_r0; 257 data = DTRACE_INVOP_DATA(invop); 258 259 /* 260 * Store the pc, lr, and sp. These have their own 261 * entries in the struct. 262 */ 263 if (data & (1 << BIT_PC)) { 264 sp--; 265 *sp = frame->tf_pc; 266 } 267 if (data & (1 << BIT_LR)) { 268 sp--; 269 *sp = frame->tf_svc_lr; 270 } 271 if (data & (1 << BIT_SP)) { 272 sp--; 273 *sp = frame->tf_svc_sp; 274 } 275 276 /* Store the general registers */ 277 for (reg = 12; reg >= 0; reg--) { 278 if (data & (1 << reg)) { 279 sp--; 280 *sp = r0[reg]; 281 } 282 } 283 284 /* Update the stack pointer and program counter to continue */ 285 frame->tf_svc_sp = (register_t)sp; 286 frame->tf_pc += 4; 287 break; 288 case DTRACE_INVOP_POPM: 289 sp = (register_t *)frame->tf_svc_sp; 290 r0 = &frame->tf_r0; 291 data = DTRACE_INVOP_DATA(invop); 292 293 /* Read the general registers */ 294 for (reg = 0; reg <= 12; reg++) { 295 if (data & (1 << reg)) { 296 r0[reg] = *sp; 297 sp++; 298 } 299 } 300 301 /* 302 * Set the stack pointer. If we don't update it here we will 303 * need to update it at the end as the instruction would do 304 */ 305 update_sp = 1; 306 if (data & (1 << BIT_SP)) { 307 frame->tf_svc_sp = *sp; 308 *sp++; 309 update_sp = 0; 310 } 311 312 /* Update the link register, we need to use the correct copy */ 313 if (data & (1 << BIT_LR)) { 314 frame->tf_svc_lr = *sp; 315 *sp++; 316 } 317 /* 318 * And the program counter. If it's not in the list skip over 319 * it when we return so to not hit this again. 320 */ 321 if (data & (1 << BIT_PC)) { 322 frame->tf_pc = *sp; 323 *sp++; 324 } else 325 frame->tf_pc += 4; 326 327 /* Update the stack pointer if we haven't already done so */ 328 if (update_sp) 329 frame->tf_svc_sp = (register_t)sp; 330 break; 331 case DTRACE_INVOP_B: 332 data = DTRACE_INVOP_DATA(invop) & 0x00ffffff; 333 /* Sign extend the data */ 334 if ((data & (1 << 23)) != 0) 335 data |= 0xff000000; 336 /* The data is the number of 4-byte words to change the pc */ 337 data *= 4; 338 data += 8; 339 frame->tf_pc += data; 340 break; 341 default: 342 return (-1); 343 break; 344 } 345 346 return (0); 347 } 348 349 void dtrace_invop_init(void) 350 { 351 dtrace_invop_jump_addr = dtrace_invop_start; 352 } 353 354 void dtrace_invop_uninit(void) 355 { 356 dtrace_invop_jump_addr = 0; 357 } 358