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 */ 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/vmparam.h> 41 #include <machine/encoding.h> 42 #include <machine/riscvreg.h> 43 #include <machine/clock.h> 44 #include <machine/frame.h> 45 #include <machine/trap.h> 46 #include <vm/pmap.h> 47 48 extern dtrace_id_t dtrace_probeid_error; 49 extern int (*dtrace_invop_jump_addr)(struct trapframe *); 50 extern void dtrace_getnanotime(struct timespec *tsp); 51 extern void dtrace_getnanouptime(struct timespec *tsp); 52 53 int dtrace_invop(uintptr_t, struct trapframe *); 54 void dtrace_invop_init(void); 55 void dtrace_invop_uninit(void); 56 57 typedef struct dtrace_invop_hdlr { 58 int (*dtih_func)(uintptr_t, struct trapframe *, uintptr_t); 59 struct dtrace_invop_hdlr *dtih_next; 60 } dtrace_invop_hdlr_t; 61 62 dtrace_invop_hdlr_t *dtrace_invop_hdlr; 63 64 int 65 dtrace_invop(uintptr_t addr, struct trapframe *frame) 66 { 67 struct thread *td; 68 dtrace_invop_hdlr_t *hdlr; 69 int rval; 70 71 rval = 0; 72 td = curthread; 73 td->t_dtrace_trapframe = frame; 74 for (hdlr = dtrace_invop_hdlr; hdlr != NULL; hdlr = hdlr->dtih_next) 75 if ((rval = hdlr->dtih_func(addr, frame, 0)) != 0) 76 break; 77 td->t_dtrace_trapframe = NULL; 78 return (rval); 79 } 80 81 void 82 dtrace_invop_add(int (*func)(uintptr_t, struct trapframe *, uintptr_t)) 83 { 84 dtrace_invop_hdlr_t *hdlr; 85 86 hdlr = kmem_alloc(sizeof (dtrace_invop_hdlr_t), KM_SLEEP); 87 hdlr->dtih_func = func; 88 hdlr->dtih_next = dtrace_invop_hdlr; 89 dtrace_invop_hdlr = hdlr; 90 } 91 92 void 93 dtrace_invop_remove(int (*func)(uintptr_t, struct trapframe *, uintptr_t)) 94 { 95 dtrace_invop_hdlr_t *hdlr, *prev; 96 97 hdlr = dtrace_invop_hdlr; 98 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 /*ARGSUSED*/ 123 void 124 dtrace_toxic_ranges(void (*func)(uintptr_t base, uintptr_t limit)) 125 { 126 127 (*func)(0, (uintptr_t)VM_MIN_KERNEL_ADDRESS); 128 } 129 130 /* 131 * DTrace needs a high resolution time function which can 132 * be called from a probe context and guaranteed not to have 133 * instrumented with probes itself. 134 * 135 * Returns nanoseconds since boot. 136 */ 137 uint64_t 138 dtrace_gethrtime(void) 139 { 140 struct timespec curtime; 141 142 dtrace_getnanouptime(&curtime); 143 144 return (curtime.tv_sec * 1000000000UL + curtime.tv_nsec); 145 146 } 147 148 uint64_t 149 dtrace_gethrestime(void) 150 { 151 struct timespec current_time; 152 153 dtrace_getnanotime(¤t_time); 154 155 return (current_time.tv_sec * 1000000000UL + current_time.tv_nsec); 156 } 157 158 /* Function to handle DTrace traps during probes. See riscv/riscv/trap.c */ 159 int 160 dtrace_trap(struct trapframe *frame, u_int type) 161 { 162 /* 163 * A trap can occur while DTrace executes a probe. Before 164 * executing the probe, DTrace blocks re-scheduling and sets 165 * a flag in its per-cpu flags to indicate that it doesn't 166 * want to fault. On returning from the probe, the no-fault 167 * flag is cleared and finally re-scheduling is enabled. 168 * 169 * Check if DTrace has enabled 'no-fault' mode: 170 */ 171 if ((cpu_core[curcpu].cpuc_dtrace_flags & CPU_DTRACE_NOFAULT) != 0) { 172 /* 173 * There are only a couple of trap types that are expected. 174 * All the rest will be handled in the usual way. 175 */ 176 switch (type) { 177 case SCAUSE_LOAD_ACCESS_FAULT: 178 case SCAUSE_STORE_ACCESS_FAULT: 179 case SCAUSE_INST_ACCESS_FAULT: 180 case SCAUSE_INST_PAGE_FAULT: 181 case SCAUSE_LOAD_PAGE_FAULT: 182 case SCAUSE_STORE_PAGE_FAULT: 183 /* Flag a bad address. */ 184 cpu_core[curcpu].cpuc_dtrace_flags |= CPU_DTRACE_BADADDR; 185 cpu_core[curcpu].cpuc_dtrace_illval = frame->tf_stval; 186 187 /* 188 * Offset the instruction pointer to the instruction 189 * following the one causing the fault. 190 */ 191 frame->tf_sepc += 192 dtrace_instr_size((uint8_t *)frame->tf_sepc); 193 194 return (1); 195 default: 196 /* Handle all other traps in the usual way. */ 197 break; 198 } 199 } 200 201 /* Handle the trap in the usual way. */ 202 return (0); 203 } 204 205 void 206 dtrace_probe_error(dtrace_state_t *state, dtrace_epid_t epid, int which, 207 int fault, int fltoffs, uintptr_t illval) 208 { 209 210 dtrace_probe(dtrace_probeid_error, (uint64_t)(uintptr_t)state, 211 (uintptr_t)epid, 212 (uintptr_t)which, (uintptr_t)fault, (uintptr_t)fltoffs); 213 } 214 215 static int 216 dtrace_invop_start(struct trapframe *frame) 217 { 218 register_t *sp; 219 uint32_t uimm; 220 uint32_t imm; 221 int invop; 222 223 invop = dtrace_invop(frame->tf_sepc, frame); 224 if (invop == 0) 225 return (-1); 226 227 if (dtrace_match_opcode(invop, (MATCH_SD | RS2_RA | RS1_SP), 228 (MASK_SD | RS2_MASK | RS1_MASK))) { 229 /* Non-compressed store of ra to sp */ 230 imm = (invop >> 7) & 0x1f; 231 imm |= ((invop >> 25) & 0x7f) << 5; 232 sp = (register_t *)((uint8_t *)frame->tf_sp + imm); 233 *sp = frame->tf_ra; 234 frame->tf_sepc += INSN_SIZE; 235 return (0); 236 } 237 238 if (dtrace_match_opcode(invop, (MATCH_JALR | (X_RA << RS1_SHIFT)), 239 (MASK_JALR | RD_MASK | RS1_MASK | IMM_MASK))) { 240 /* Non-compressed ret */ 241 frame->tf_sepc = frame->tf_ra; 242 return (0); 243 } 244 245 if (dtrace_match_opcode(invop, (MATCH_C_SDSP | RS2_C_RA), 246 (MASK_C_SDSP | RS2_C_MASK))) { 247 /* 'C'-compressed store of ra to sp */ 248 uimm = ((invop >> 10) & 0x7) << 3; 249 uimm |= ((invop >> 7) & 0x7) << 6; 250 sp = (register_t *)((uint8_t *)frame->tf_sp + uimm); 251 *sp = frame->tf_ra; 252 frame->tf_sepc += INSN_C_SIZE; 253 return (0); 254 } 255 256 if (dtrace_match_opcode(invop, (MATCH_C_JR | (X_RA << RD_SHIFT)), 257 (MASK_C_JR | RD_MASK))) { 258 /* 'C'-compressed ret */ 259 frame->tf_sepc = frame->tf_ra; 260 return (0); 261 } 262 263 if (dtrace_match_opcode(invop, MATCH_C_NOP, MASK_C_NOP)) 264 return (0); 265 266 #ifdef INVARIANTS 267 panic("Instruction %x doesn't match any opcode.", invop); 268 #endif 269 270 return (-1); 271 } 272 273 void 274 dtrace_invop_init(void) 275 { 276 277 dtrace_invop_jump_addr = dtrace_invop_start; 278 } 279 280 void 281 dtrace_invop_uninit(void) 282 { 283 284 dtrace_invop_jump_addr = 0; 285 } 286