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 (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 * 21 * Portions Copyright 2006-2008 John Birrell jb@freebsd.org 22 * Portions Copyright 2013 Justin Hibbits jhibbits@freebsd.org 23 * Portions Copyright 2013 Howard Su howardsu@freebsd.org 24 * Portions Copyright 2016-2018 Ruslan Bukin <br@bsdpad.com> 25 * 26 * $FreeBSD$ 27 */ 28 29 /* 30 * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 31 * Use is subject to license terms. 32 */ 33 34 #include <sys/cdefs.h> 35 #include <sys/param.h> 36 37 #include <sys/dtrace.h> 38 39 #include <machine/riscvreg.h> 40 #include <machine/encoding.h> 41 42 #include "fbt.h" 43 44 #define FBT_C_PATCHVAL MATCH_C_EBREAK 45 #define FBT_PATCHVAL MATCH_EBREAK 46 #define FBT_ENTRY "entry" 47 #define FBT_RETURN "return" 48 49 int 50 fbt_invop(uintptr_t addr, struct trapframe *frame, uintptr_t rval) 51 { 52 solaris_cpu_t *cpu; 53 fbt_probe_t *fbt; 54 55 cpu = &solaris_cpu[curcpu]; 56 fbt = fbt_probetab[FBT_ADDR2NDX(addr)]; 57 58 for (; fbt != NULL; fbt = fbt->fbtp_hashnext) { 59 if ((uintptr_t)fbt->fbtp_patchpoint == addr) { 60 cpu->cpu_dtrace_caller = addr; 61 62 if (fbt->fbtp_roffset == 0) { 63 dtrace_probe(fbt->fbtp_id, frame->tf_a[0], 64 frame->tf_a[1], frame->tf_a[2], 65 frame->tf_a[3], frame->tf_a[4]); 66 } else { 67 dtrace_probe(fbt->fbtp_id, fbt->fbtp_roffset, 68 frame->tf_a[0], frame->tf_a[1], 0, 0); 69 } 70 71 cpu->cpu_dtrace_caller = 0; 72 return (fbt->fbtp_savedval); 73 } 74 } 75 76 return (0); 77 } 78 79 void 80 fbt_patch_tracepoint(fbt_probe_t *fbt, fbt_patchval_t val) 81 { 82 83 switch(fbt->fbtp_patchval) { 84 case FBT_C_PATCHVAL: 85 *(uint16_t *)fbt->fbtp_patchpoint = (uint16_t)val; 86 fence_i(); 87 break; 88 case FBT_PATCHVAL: 89 *fbt->fbtp_patchpoint = val; 90 fence_i(); 91 break; 92 }; 93 } 94 95 static int 96 match_opcode(uint32_t insn, int match, int mask) 97 { 98 99 if (((insn ^ match) & mask) == 0) 100 return (1); 101 102 return (0); 103 } 104 105 static int 106 check_c_ret(uint32_t **instr) 107 { 108 uint16_t *instr1; 109 int i; 110 111 for (i = 0; i < 2; i++) { 112 instr1 = (uint16_t *)(*instr) + i; 113 if (match_opcode(*instr1, (MATCH_C_JR | (X_RA << RD_SHIFT)), 114 (MASK_C_JR | RD_MASK))) { 115 *instr = (uint32_t *)instr1; 116 return (1); 117 } 118 } 119 120 return (0); 121 } 122 123 static int 124 check_c_sdsp(uint32_t **instr) 125 { 126 uint16_t *instr1; 127 int i; 128 129 for (i = 0; i < 2; i++) { 130 instr1 = (uint16_t *)(*instr) + i; 131 if (match_opcode(*instr1, (MATCH_C_SDSP | RS2_C_RA), 132 (MASK_C_SDSP | RS2_C_MASK))) { 133 *instr = (uint32_t *)instr1; 134 return (1); 135 } 136 } 137 138 return (0); 139 } 140 141 int 142 fbt_provide_module_function(linker_file_t lf, int symindx, 143 linker_symval_t *symval, void *opaque) 144 { 145 fbt_probe_t *fbt, *retfbt; 146 uint32_t *instr, *limit; 147 const char *name; 148 char *modname; 149 int patchval; 150 int rval; 151 152 modname = opaque; 153 name = symval->name; 154 155 /* Check if function is excluded from instrumentation */ 156 if (fbt_excluded(name)) 157 return (0); 158 159 instr = (uint32_t *)(symval->value); 160 limit = (uint32_t *)(symval->value + symval->size); 161 162 /* Look for sd operation */ 163 for (; instr < limit; instr++) { 164 /* Look for a non-compressed store of ra to sp */ 165 if (match_opcode(*instr, (MATCH_SD | RS2_RA | RS1_SP), 166 (MASK_SD | RS2_MASK | RS1_MASK))) { 167 rval = DTRACE_INVOP_SD; 168 patchval = FBT_PATCHVAL; 169 break; 170 } 171 172 /* Look for a 'C'-compressed store of ra to sp. */ 173 if (check_c_sdsp(&instr)) { 174 rval = DTRACE_INVOP_C_SDSP; 175 patchval = FBT_C_PATCHVAL; 176 break; 177 } 178 } 179 180 if (instr >= limit) 181 return (0); 182 183 fbt = malloc(sizeof (fbt_probe_t), M_FBT, M_WAITOK | M_ZERO); 184 fbt->fbtp_name = name; 185 fbt->fbtp_id = dtrace_probe_create(fbt_id, modname, 186 name, FBT_ENTRY, 3, fbt); 187 fbt->fbtp_patchpoint = instr; 188 fbt->fbtp_ctl = lf; 189 fbt->fbtp_loadcnt = lf->loadcnt; 190 fbt->fbtp_savedval = *instr; 191 fbt->fbtp_patchval = patchval; 192 fbt->fbtp_rval = rval; 193 fbt->fbtp_symindx = symindx; 194 195 fbt->fbtp_hashnext = fbt_probetab[FBT_ADDR2NDX(instr)]; 196 fbt_probetab[FBT_ADDR2NDX(instr)] = fbt; 197 198 lf->fbt_nentries++; 199 200 retfbt = NULL; 201 again: 202 for (; instr < limit; instr++) { 203 /* Look for non-compressed return */ 204 if (match_opcode(*instr, (MATCH_JALR | (X_RA << RS1_SHIFT)), 205 (MASK_JALR | RD_MASK | RS1_MASK | IMM_MASK))) { 206 rval = DTRACE_INVOP_RET; 207 patchval = FBT_PATCHVAL; 208 break; 209 } 210 211 /* Look for 'C'-compressed return */ 212 if (check_c_ret(&instr)) { 213 rval = DTRACE_INVOP_C_RET; 214 patchval = FBT_C_PATCHVAL; 215 break; 216 } 217 } 218 219 if (instr >= limit) 220 return (0); 221 222 /* 223 * We have a winner! 224 */ 225 fbt = malloc(sizeof (fbt_probe_t), M_FBT, M_WAITOK | M_ZERO); 226 fbt->fbtp_name = name; 227 if (retfbt == NULL) { 228 fbt->fbtp_id = dtrace_probe_create(fbt_id, modname, 229 name, FBT_RETURN, 3, fbt); 230 } else { 231 retfbt->fbtp_probenext = fbt; 232 fbt->fbtp_id = retfbt->fbtp_id; 233 } 234 retfbt = fbt; 235 236 fbt->fbtp_patchpoint = instr; 237 fbt->fbtp_ctl = lf; 238 fbt->fbtp_loadcnt = lf->loadcnt; 239 fbt->fbtp_symindx = symindx; 240 fbt->fbtp_rval = rval; 241 fbt->fbtp_roffset = (uintptr_t)instr - (uintptr_t)symval->value; 242 fbt->fbtp_savedval = *instr; 243 fbt->fbtp_patchval = patchval; 244 fbt->fbtp_hashnext = fbt_probetab[FBT_ADDR2NDX(instr)]; 245 fbt_probetab[FBT_ADDR2NDX(instr)] = fbt; 246 247 lf->fbt_nentries++; 248 249 instr++; 250 goto again; 251 } 252