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 #include <machine/trap.h> 39 40 #include "fbt.h" 41 42 #define FBT_PUSHM 0xe92d0000 43 #define FBT_POPM 0xe8bd0000 44 #define FBT_JUMP 0xea000000 45 46 #define FBT_ENTRY "entry" 47 #define FBT_RETURN "return" 48 49 int 50 fbt_invop(uintptr_t addr, uintptr_t *stack, uintptr_t rval) 51 { 52 struct trapframe *frame = (struct trapframe *)stack; 53 solaris_cpu_t *cpu = &solaris_cpu[curcpu]; 54 fbt_probe_t *fbt = fbt_probetab[FBT_ADDR2NDX(addr)]; 55 register_t fifthparam; 56 57 for (; fbt != NULL; fbt = fbt->fbtp_hashnext) { 58 if ((uintptr_t)fbt->fbtp_patchpoint == addr) { 59 cpu->cpu_dtrace_caller = addr; 60 61 /* Get 5th parameter from stack */ 62 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); 63 fifthparam = *(register_t *)frame->tf_usr_sp; 64 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT | CPU_DTRACE_BADADDR); 65 66 dtrace_probe(fbt->fbtp_id, frame->tf_r0, 67 frame->tf_r1, frame->tf_r2, 68 frame->tf_r3, fifthparam); 69 70 cpu->cpu_dtrace_caller = 0; 71 72 return (fbt->fbtp_rval | (fbt->fbtp_savedval << DTRACE_INVOP_SHIFT)); 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 *fbt->fbtp_patchpoint = val; 84 cpu_icache_sync_range((vm_offset_t)fbt->fbtp_patchpoint, sizeof(val)); 85 } 86 87 int 88 fbt_provide_module_function(linker_file_t lf, int symindx, 89 linker_symval_t *symval, void *opaque) 90 { 91 char *modname = opaque; 92 const char *name = symval->name; 93 fbt_probe_t *fbt, *retfbt; 94 uint32_t *instr, *limit; 95 int popm; 96 97 if (strncmp(name, "dtrace_", 7) == 0 && 98 strncmp(name, "dtrace_safe_", 12) != 0) { 99 /* 100 * Anything beginning with "dtrace_" may be called 101 * from probe context unless it explicitly indicates 102 * that it won't be called from probe context by 103 * using the prefix "dtrace_safe_". 104 */ 105 return (0); 106 } 107 108 if (name[0] == '_' && name[1] == '_') 109 return (0); 110 111 instr = (uint32_t *)symval->value; 112 limit = (uint32_t *)(symval->value + symval->size); 113 114 for (; instr < limit; instr++) 115 if ((*instr & 0xffff0000) == FBT_PUSHM && 116 (*instr & 0x4000) != 0) 117 break; 118 119 if (instr >= limit) 120 return (0); 121 122 fbt = malloc(sizeof (fbt_probe_t), M_FBT, M_WAITOK | M_ZERO); 123 fbt->fbtp_name = name; 124 fbt->fbtp_id = dtrace_probe_create(fbt_id, modname, 125 name, FBT_ENTRY, 2, fbt); 126 fbt->fbtp_patchpoint = instr; 127 fbt->fbtp_ctl = lf; 128 fbt->fbtp_loadcnt = lf->loadcnt; 129 fbt->fbtp_savedval = *instr; 130 fbt->fbtp_patchval = FBT_BREAKPOINT; 131 fbt->fbtp_rval = DTRACE_INVOP_PUSHM; 132 fbt->fbtp_symindx = symindx; 133 134 fbt->fbtp_hashnext = fbt_probetab[FBT_ADDR2NDX(instr)]; 135 fbt_probetab[FBT_ADDR2NDX(instr)] = fbt; 136 137 lf->fbt_nentries++; 138 139 popm = FBT_POPM | ((*instr) & 0x3FFF) | 0x8000; 140 141 retfbt = NULL; 142 again: 143 for (; instr < limit; instr++) { 144 if (*instr == popm) 145 break; 146 else if ((*instr & 0xff000000) == FBT_JUMP) { 147 uint32_t *target, *start; 148 int offset; 149 150 offset = (*instr & 0xffffff); 151 offset <<= 8; 152 offset /= 64; 153 target = instr + (2 + offset); 154 start = (uint32_t *)symval->value; 155 if (target >= limit || target < start) 156 break; 157 } 158 } 159 160 if (instr >= limit) 161 return (0); 162 163 /* 164 * We have a winner! 165 */ 166 fbt = malloc(sizeof (fbt_probe_t), M_FBT, M_WAITOK | M_ZERO); 167 fbt->fbtp_name = name; 168 if (retfbt == NULL) { 169 fbt->fbtp_id = dtrace_probe_create(fbt_id, modname, 170 name, FBT_RETURN, 2, fbt); 171 } else { 172 retfbt->fbtp_next = fbt; 173 fbt->fbtp_id = retfbt->fbtp_id; 174 } 175 retfbt = fbt; 176 177 fbt->fbtp_patchpoint = instr; 178 fbt->fbtp_ctl = lf; 179 fbt->fbtp_loadcnt = lf->loadcnt; 180 fbt->fbtp_symindx = symindx; 181 if ((*instr & 0xff000000) == FBT_JUMP) 182 fbt->fbtp_rval = DTRACE_INVOP_B; 183 else 184 fbt->fbtp_rval = DTRACE_INVOP_POPM; 185 fbt->fbtp_savedval = *instr; 186 fbt->fbtp_patchval = FBT_BREAKPOINT; 187 fbt->fbtp_hashnext = fbt_probetab[FBT_ADDR2NDX(instr)]; 188 fbt_probetab[FBT_ADDR2NDX(instr)] = fbt; 189 190 lf->fbt_nentries++; 191 192 instr++; 193 goto again; 194 } 195