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 * Portions Copyright 2016-2018 Ruslan Bukin <br@bsdpad.com> 23 * 24 * $FreeBSD$ 25 * 26 */ 27 /* 28 * Copyright 2005 Sun Microsystems, Inc. All rights reserved. 29 * Use is subject to license terms. 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 #include <sys/param.h> 36 #include <sys/systm.h> 37 #include <sys/types.h> 38 #include <sys/kernel.h> 39 #include <sys/malloc.h> 40 #include <sys/kmem.h> 41 #include <sys/smp.h> 42 #include <sys/dtrace_impl.h> 43 #include <sys/dtrace_bsd.h> 44 #include <machine/vmparam.h> 45 #include <machine/encoding.h> 46 #include <machine/riscvreg.h> 47 #include <machine/clock.h> 48 #include <machine/frame.h> 49 #include <machine/trap.h> 50 #include <vm/pmap.h> 51 52 extern dtrace_id_t dtrace_probeid_error; 53 extern int (*dtrace_invop_jump_addr)(struct trapframe *); 54 extern void dtrace_getnanotime(struct timespec *tsp); 55 56 int dtrace_invop(uintptr_t, struct trapframe *, uintptr_t); 57 void dtrace_invop_init(void); 58 void dtrace_invop_uninit(void); 59 60 typedef struct dtrace_invop_hdlr { 61 int (*dtih_func)(uintptr_t, struct trapframe *, uintptr_t); 62 struct dtrace_invop_hdlr *dtih_next; 63 } dtrace_invop_hdlr_t; 64 65 dtrace_invop_hdlr_t *dtrace_invop_hdlr; 66 67 int 68 dtrace_invop(uintptr_t addr, struct trapframe *frame, uintptr_t eax) 69 { 70 dtrace_invop_hdlr_t *hdlr; 71 int rval; 72 73 for (hdlr = dtrace_invop_hdlr; hdlr != NULL; hdlr = hdlr->dtih_next) 74 if ((rval = hdlr->dtih_func(addr, frame, eax)) != 0) 75 return (rval); 76 77 return (0); 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 158 * be called from a probe context and guaranteed not to have 159 * instrumented with probes itself. 160 * 161 * Returns nanoseconds since boot. 162 */ 163 uint64_t 164 dtrace_gethrtime() 165 { 166 struct timespec curtime; 167 168 nanouptime(&curtime); 169 170 return (curtime.tv_sec * 1000000000UL + curtime.tv_nsec); 171 172 } 173 174 uint64_t 175 dtrace_gethrestime(void) 176 { 177 struct timespec current_time; 178 179 dtrace_getnanotime(¤t_time); 180 181 return (current_time.tv_sec * 1000000000UL + current_time.tv_nsec); 182 } 183 184 /* Function to handle DTrace traps during probes. See riscv/riscv/trap.c */ 185 int 186 dtrace_trap(struct trapframe *frame, u_int type) 187 { 188 /* 189 * A trap can occur while DTrace executes a probe. Before 190 * executing the probe, DTrace blocks re-scheduling and sets 191 * a flag in its per-cpu flags to indicate that it doesn't 192 * want to fault. On returning from the probe, the no-fault 193 * flag is cleared and finally re-scheduling is enabled. 194 * 195 * Check if DTrace has enabled 'no-fault' mode: 196 * 197 */ 198 199 if ((cpu_core[curcpu].cpuc_dtrace_flags & CPU_DTRACE_NOFAULT) != 0) { 200 /* 201 * There are only a couple of trap types that are expected. 202 * All the rest will be handled in the usual way. 203 */ 204 switch (type) { 205 case EXCP_FAULT_LOAD: 206 case EXCP_FAULT_STORE: 207 case EXCP_FAULT_FETCH: 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_sepc += 4; 217 218 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 int 240 match_opcode(uint32_t insn, int match, int mask) 241 { 242 243 if (((insn ^ match) & mask) == 0) 244 return (1); 245 246 return (0); 247 } 248 249 static int 250 dtrace_invop_start(struct trapframe *frame) 251 { 252 register_t *sp; 253 uint32_t uimm; 254 uint32_t imm; 255 int invop; 256 257 invop = dtrace_invop(frame->tf_sepc, frame, frame->tf_sepc); 258 if (invop == 0) 259 return (-1); 260 261 if (match_opcode(invop, (MATCH_SD | RS2_RA | RS1_SP), 262 (MASK_SD | RS2_MASK | RS1_MASK))) { 263 /* Non-compressed store of ra to sp */ 264 imm = (invop >> 7) & 0x1f; 265 imm |= ((invop >> 25) & 0x7f) << 5; 266 sp = (register_t *)((uint8_t *)frame->tf_sp + imm); 267 *sp = frame->tf_ra; 268 frame->tf_sepc += INSN_SIZE; 269 return (0); 270 } 271 272 if (match_opcode(invop, (MATCH_JALR | (X_RA << RS1_SHIFT)), 273 (MASK_JALR | RD_MASK | RS1_MASK | IMM_MASK))) { 274 /* Non-compressed ret */ 275 frame->tf_sepc = frame->tf_ra; 276 return (0); 277 } 278 279 if (match_opcode(invop, (MATCH_C_SDSP | RS2_C_RA), 280 (MASK_C_SDSP | RS2_C_MASK))) { 281 /* 'C'-compressed store of ra to sp */ 282 uimm = ((invop >> 10) & 0x7) << 3; 283 uimm |= ((invop >> 7) & 0x7) << 6; 284 sp = (register_t *)((uint8_t *)frame->tf_sp + uimm); 285 *sp = frame->tf_ra; 286 frame->tf_sepc += INSN_C_SIZE; 287 return (0); 288 } 289 290 if (match_opcode(invop, (MATCH_C_JR | (X_RA << RD_SHIFT)), 291 (MASK_C_JR | RD_MASK))) { 292 /* 'C'-compressed ret */ 293 frame->tf_sepc = frame->tf_ra; 294 return (0); 295 } 296 297 #ifdef INVARIANTS 298 panic("Instruction %x doesn't match any opcode.", invop); 299 #endif 300 301 return (-1); 302 } 303 304 void 305 dtrace_invop_init(void) 306 { 307 308 dtrace_invop_jump_addr = dtrace_invop_start; 309 } 310 311 void 312 dtrace_invop_uninit(void) 313 { 314 315 dtrace_invop_jump_addr = 0; 316 } 317