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 <vm/pmap.h> 43 44 #define DELAYBRANCH(x) ((int)(x) < 0) 45 46 #define BIT_PC 15 47 #define BIT_LR 14 48 #define BIT_SP 13 49 50 extern dtrace_id_t dtrace_probeid_error; 51 extern int (*dtrace_invop_jump_addr)(struct trapframe *); 52 extern void dtrace_getnanotime(struct timespec *tsp); 53 extern void dtrace_getnanouptime(struct timespec *tsp); 54 55 int dtrace_invop(uintptr_t, struct trapframe *, uintptr_t); 56 void dtrace_invop_init(void); 57 void dtrace_invop_uninit(void); 58 59 typedef struct dtrace_invop_hdlr { 60 int (*dtih_func)(uintptr_t, struct trapframe *, uintptr_t); 61 struct dtrace_invop_hdlr *dtih_next; 62 } dtrace_invop_hdlr_t; 63 64 dtrace_invop_hdlr_t *dtrace_invop_hdlr; 65 66 int 67 dtrace_invop(uintptr_t addr, struct trapframe *frame, uintptr_t eax) 68 { 69 struct thread *td; 70 dtrace_invop_hdlr_t *hdlr; 71 int rval; 72 73 rval = 0; 74 td = curthread; 75 td->t_dtrace_trapframe = frame; 76 for (hdlr = dtrace_invop_hdlr; hdlr != NULL; hdlr = hdlr->dtih_next) 77 if ((rval = hdlr->dtih_func(addr, frame, eax)) != 0) 78 break; 79 td->t_dtrace_trapframe = NULL; 80 return (rval); 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 /* 142 * DTrace needs a high resolution time function which can 143 * be called from a probe context and guaranteed not to have 144 * instrumented with probes itself. 145 * 146 * Returns nanoseconds since boot. 147 */ 148 uint64_t 149 dtrace_gethrtime(void) 150 { 151 struct timespec curtime; 152 153 dtrace_getnanouptime(&curtime); 154 155 return (curtime.tv_sec * 1000000000UL + curtime.tv_nsec); 156 157 } 158 159 uint64_t 160 dtrace_gethrestime(void) 161 { 162 struct timespec current_time; 163 164 dtrace_getnanotime(¤t_time); 165 166 return (current_time.tv_sec * 1000000000UL + current_time.tv_nsec); 167 } 168 169 /* Function to handle DTrace traps during probes. See amd64/amd64/trap.c */ 170 int 171 dtrace_trap(struct trapframe *frame, u_int type) 172 { 173 /* 174 * A trap can occur while DTrace executes a probe. Before 175 * executing the probe, DTrace blocks re-scheduling and sets 176 * a flag in its per-cpu flags to indicate that it doesn't 177 * want to fault. On returning from the probe, the no-fault 178 * flag is cleared and finally re-scheduling is enabled. 179 * 180 * Check if DTrace has enabled 'no-fault' mode: 181 * 182 */ 183 if ((cpu_core[curcpu].cpuc_dtrace_flags & CPU_DTRACE_NOFAULT) != 0) { 184 /* 185 * There are only a couple of trap types that are expected. 186 * All the rest will be handled in the usual way. 187 */ 188 switch (type) { 189 /* Page fault. */ 190 case FAULT_ALIGN: 191 /* Flag a bad address. */ 192 cpu_core[curcpu].cpuc_dtrace_flags |= CPU_DTRACE_BADADDR; 193 cpu_core[curcpu].cpuc_dtrace_illval = 0; 194 195 /* 196 * Offset the instruction pointer to the instruction 197 * following the one causing the fault. 198 */ 199 frame->tf_pc += sizeof(int); 200 return (1); 201 default: 202 /* Handle all other traps in the usual way. */ 203 break; 204 } 205 } 206 207 /* Handle the trap in the usual way. */ 208 return (0); 209 } 210 211 void 212 dtrace_probe_error(dtrace_state_t *state, dtrace_epid_t epid, int which, 213 int fault, int fltoffs, uintptr_t illval) 214 { 215 216 dtrace_probe(dtrace_probeid_error, (uint64_t)(uintptr_t)state, 217 (uintptr_t)epid, 218 (uintptr_t)which, (uintptr_t)fault, (uintptr_t)fltoffs); 219 } 220 221 static int 222 dtrace_invop_start(struct trapframe *frame) 223 { 224 register_t *r0, *sp; 225 int data, invop, reg, update_sp; 226 227 invop = dtrace_invop(frame->tf_pc, frame, frame->tf_r0); 228 switch (invop & DTRACE_INVOP_MASK) { 229 case DTRACE_INVOP_PUSHM: 230 sp = (register_t *)frame->tf_svc_sp; 231 r0 = &frame->tf_r0; 232 data = DTRACE_INVOP_DATA(invop); 233 234 /* 235 * Store the pc, lr, and sp. These have their own 236 * entries in the struct. 237 */ 238 if (data & (1 << BIT_PC)) { 239 sp--; 240 *sp = frame->tf_pc; 241 } 242 if (data & (1 << BIT_LR)) { 243 sp--; 244 *sp = frame->tf_svc_lr; 245 } 246 if (data & (1 << BIT_SP)) { 247 sp--; 248 *sp = frame->tf_svc_sp; 249 } 250 251 /* Store the general registers */ 252 for (reg = 12; reg >= 0; reg--) { 253 if (data & (1 << reg)) { 254 sp--; 255 *sp = r0[reg]; 256 } 257 } 258 259 /* Update the stack pointer and program counter to continue */ 260 frame->tf_svc_sp = (register_t)sp; 261 frame->tf_pc += 4; 262 break; 263 case DTRACE_INVOP_POPM: 264 sp = (register_t *)frame->tf_svc_sp; 265 r0 = &frame->tf_r0; 266 data = DTRACE_INVOP_DATA(invop); 267 268 /* Read the general registers */ 269 for (reg = 0; reg <= 12; reg++) { 270 if (data & (1 << reg)) { 271 r0[reg] = *sp; 272 sp++; 273 } 274 } 275 276 /* 277 * Set the stack pointer. If we don't update it here we will 278 * need to update it at the end as the instruction would do 279 */ 280 update_sp = 1; 281 if (data & (1 << BIT_SP)) { 282 frame->tf_svc_sp = *sp; 283 *sp++; 284 update_sp = 0; 285 } 286 287 /* Update the link register, we need to use the correct copy */ 288 if (data & (1 << BIT_LR)) { 289 frame->tf_svc_lr = *sp; 290 *sp++; 291 } 292 /* 293 * And the program counter. If it's not in the list skip over 294 * it when we return so to not hit this again. 295 */ 296 if (data & (1 << BIT_PC)) { 297 frame->tf_pc = *sp; 298 *sp++; 299 } else 300 frame->tf_pc += 4; 301 302 /* Update the stack pointer if we haven't already done so */ 303 if (update_sp) 304 frame->tf_svc_sp = (register_t)sp; 305 break; 306 case DTRACE_INVOP_B: 307 data = DTRACE_INVOP_DATA(invop) & 0x00ffffff; 308 /* Sign extend the data */ 309 if ((data & (1 << 23)) != 0) 310 data |= 0xff000000; 311 /* The data is the number of 4-byte words to change the pc */ 312 data *= 4; 313 data += 8; 314 frame->tf_pc += data; 315 break; 316 default: 317 return (-1); 318 break; 319 } 320 321 return (0); 322 } 323 324 void dtrace_invop_init(void) 325 { 326 dtrace_invop_jump_addr = dtrace_invop_start; 327 } 328 329 void dtrace_invop_uninit(void) 330 { 331 dtrace_invop_jump_addr = 0; 332 } 333