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 * 25 * $FreeBSD$ 26 * 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 "fbt.h" 40 41 #define FBT_PATCHVAL 0xe7f000f0 /* Specified undefined instruction */ 42 43 #define FBT_PUSHM 0xe92d0000 44 #define FBT_POPM 0xe8bd0000 45 #define FBT_JUMP 0xea000000 46 47 #define FBT_ENTRY "entry" 48 #define FBT_RETURN "return" 49 50 int 51 fbt_invop(uintptr_t addr, uintptr_t *stack, uintptr_t rval) 52 { 53 struct trapframe *frame = (struct trapframe *)stack; 54 solaris_cpu_t *cpu = &solaris_cpu[curcpu]; 55 fbt_probe_t *fbt = fbt_probetab[FBT_ADDR2NDX(addr)]; 56 57 for (; fbt != NULL; fbt = fbt->fbtp_hashnext) { 58 if ((uintptr_t)fbt->fbtp_patchpoint == addr) { 59 fbt->fbtp_invop_cnt++; 60 cpu->cpu_dtrace_caller = addr; 61 62 /* TODO: Need 5th parameter from stack */ 63 dtrace_probe(fbt->fbtp_id, frame->tf_r0, 64 frame->tf_r1, frame->tf_r2, 65 frame->tf_r3, 0); 66 67 cpu->cpu_dtrace_caller = 0; 68 69 return (fbt->fbtp_rval | (fbt->fbtp_savedval << DTRACE_INVOP_SHIFT)); 70 } 71 } 72 73 return (0); 74 } 75 76 void 77 fbt_patch_tracepoint(fbt_probe_t *fbt, fbt_patchval_t val) 78 { 79 80 *fbt->fbtp_patchpoint = val; 81 cpu_icache_sync_range((vm_offset_t)fbt->fbtp_patchpoint, 4); 82 } 83 84 int 85 fbt_provide_module_function(linker_file_t lf, int symindx, 86 linker_symval_t *symval, void *opaque) 87 { 88 char *modname = opaque; 89 const char *name = symval->name; 90 fbt_probe_t *fbt, *retfbt; 91 uint32_t *instr, *limit; 92 int popm; 93 94 if (strncmp(name, "dtrace_", 7) == 0 && 95 strncmp(name, "dtrace_safe_", 12) != 0) { 96 /* 97 * Anything beginning with "dtrace_" may be called 98 * from probe context unless it explicitly indicates 99 * that it won't be called from probe context by 100 * using the prefix "dtrace_safe_". 101 */ 102 return (0); 103 } 104 105 if (name[0] == '_' && name[1] == '_') 106 return (0); 107 108 /* 109 * Architecture-specific exclusion list, largely to do with FBT trap 110 * processing, to prevent reentrance. 111 */ 112 if (strcmp(name, "undefinedinstruction") == 0) 113 return (0); 114 115 instr = (uint32_t *)symval->value; 116 limit = (uint32_t *)(symval->value + symval->size); 117 118 for (; instr < limit; instr++) 119 if ((*instr & 0xffff0000) == FBT_PUSHM && 120 (*instr & 0x4000) != 0) 121 break; 122 123 if (instr >= limit) 124 return (0); 125 126 fbt = malloc(sizeof (fbt_probe_t), M_FBT, M_WAITOK | M_ZERO); 127 fbt->fbtp_name = name; 128 fbt->fbtp_id = dtrace_probe_create(fbt_id, modname, 129 name, FBT_ENTRY, 3, fbt); 130 fbt->fbtp_patchpoint = instr; 131 fbt->fbtp_ctl = lf; 132 fbt->fbtp_loadcnt = lf->loadcnt; 133 fbt->fbtp_savedval = *instr; 134 fbt->fbtp_patchval = FBT_PATCHVAL; 135 fbt->fbtp_rval = DTRACE_INVOP_PUSHM; 136 fbt->fbtp_symindx = symindx; 137 138 fbt->fbtp_hashnext = fbt_probetab[FBT_ADDR2NDX(instr)]; 139 fbt_probetab[FBT_ADDR2NDX(instr)] = fbt; 140 141 lf->fbt_nentries++; 142 143 popm = FBT_POPM | ((*instr) & 0x3FFF) | 0x8000; 144 145 retfbt = NULL; 146 again: 147 for (; instr < limit; instr++) { 148 if (*instr == popm) 149 break; 150 else if ((*instr & 0xff000000) == FBT_JUMP) { 151 uint32_t *target, *start; 152 int offset; 153 154 offset = (*instr & 0xffffff); 155 offset <<= 8; 156 offset /= 64; 157 target = instr + (2 + offset); 158 start = (uint32_t *)symval->value; 159 if (target >= limit || target < start) 160 break; 161 instr++; /* skip delay slot */ 162 } 163 } 164 165 if (instr >= limit) 166 return (0); 167 168 /* 169 * We have a winner! 170 */ 171 fbt = malloc(sizeof (fbt_probe_t), M_FBT, M_WAITOK | M_ZERO); 172 fbt->fbtp_name = name; 173 if (retfbt == NULL) { 174 fbt->fbtp_id = dtrace_probe_create(fbt_id, modname, 175 name, FBT_RETURN, 5, fbt); 176 } else { 177 retfbt->fbtp_next = fbt; 178 fbt->fbtp_id = retfbt->fbtp_id; 179 } 180 retfbt = fbt; 181 182 fbt->fbtp_patchpoint = instr; 183 fbt->fbtp_ctl = lf; 184 fbt->fbtp_loadcnt = lf->loadcnt; 185 fbt->fbtp_symindx = symindx; 186 if ((*instr & 0xff000000) == FBT_JUMP) 187 fbt->fbtp_rval = DTRACE_INVOP_B; 188 else 189 fbt->fbtp_rval = DTRACE_INVOP_POPM; 190 fbt->fbtp_savedval = *instr; 191 fbt->fbtp_patchval = FBT_PATCHVAL; 192 fbt->fbtp_hashnext = fbt_probetab[FBT_ADDR2NDX(instr)]; 193 fbt_probetab[FBT_ADDR2NDX(instr)] = fbt; 194 195 lf->fbt_nentries++; 196 197 instr++; 198 goto again; 199 } 200