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 2015 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 "fbt.h" 40 41 #define AARCH64_BRK 0xd4200000 42 #define AARCH64_BRK_IMM16_SHIFT 5 43 #define AARCH64_BRK_IMM16_VAL (0x40d << AARCH64_BRK_IMM16_SHIFT) 44 #define FBT_PATCHVAL (AARCH64_BRK | AARCH64_BRK_IMM16_VAL) 45 #define FBT_ENTRY "entry" 46 #define FBT_RETURN "return" 47 48 int 49 fbt_invop(uintptr_t addr, struct trapframe *frame, uintptr_t rval) 50 { 51 solaris_cpu_t *cpu; 52 fbt_probe_t *fbt; 53 54 cpu = &solaris_cpu[curcpu]; 55 fbt = fbt_probetab[FBT_ADDR2NDX(addr)]; 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 dtrace_probe(fbt->fbtp_id, frame->tf_x[0], 62 frame->tf_x[1], frame->tf_x[2], 63 frame->tf_x[3], frame->tf_x[4]); 64 65 cpu->cpu_dtrace_caller = 0; 66 return (fbt->fbtp_savedval); 67 } 68 } 69 70 return (0); 71 } 72 73 void 74 fbt_patch_tracepoint(fbt_probe_t *fbt, fbt_patchval_t val) 75 { 76 77 *fbt->fbtp_patchpoint = val; 78 cpu_icache_sync_range((vm_offset_t)fbt->fbtp_patchpoint, 4); 79 } 80 81 int 82 fbt_provide_module_function(linker_file_t lf, int symindx, 83 linker_symval_t *symval, void *opaque) 84 { 85 fbt_probe_t *fbt, *retfbt; 86 uint32_t *target, *start; 87 uint32_t *instr, *limit; 88 const char *name; 89 char *modname; 90 int offs; 91 92 modname = opaque; 93 name = symval->name; 94 95 /* Check if function is excluded from instrumentation */ 96 if (fbt_excluded(name)) 97 return (0); 98 99 /* 100 * Instrumenting certain exception handling functions can lead to FBT 101 * recursion, so exclude from instrumentation. 102 */ 103 if (strcmp(name, "handle_el1h_sync") == 0 || 104 strcmp(name, "do_el1h_sync") == 0) 105 return (1); 106 107 instr = (uint32_t *)(symval->value); 108 limit = (uint32_t *)(symval->value + symval->size); 109 110 /* Look for stp (pre-indexed) operation */ 111 for (; instr < limit; instr++) { 112 if ((*instr & LDP_STP_MASK) == STP_64) 113 break; 114 } 115 116 if (instr >= limit) 117 return (0); 118 119 fbt = malloc(sizeof (fbt_probe_t), M_FBT, M_WAITOK | M_ZERO); 120 fbt->fbtp_name = name; 121 fbt->fbtp_id = dtrace_probe_create(fbt_id, modname, 122 name, FBT_ENTRY, 3, fbt); 123 fbt->fbtp_patchpoint = instr; 124 fbt->fbtp_ctl = lf; 125 fbt->fbtp_loadcnt = lf->loadcnt; 126 fbt->fbtp_savedval = *instr; 127 fbt->fbtp_patchval = FBT_PATCHVAL; 128 fbt->fbtp_rval = DTRACE_INVOP_PUSHM; 129 fbt->fbtp_symindx = symindx; 130 131 fbt->fbtp_hashnext = fbt_probetab[FBT_ADDR2NDX(instr)]; 132 fbt_probetab[FBT_ADDR2NDX(instr)] = fbt; 133 134 lf->fbt_nentries++; 135 136 retfbt = NULL; 137 again: 138 for (; instr < limit; instr++) { 139 if (*instr == RET_INSTR) 140 break; 141 else if ((*instr & B_MASK) == B_INSTR) { 142 offs = (*instr & B_DATA_MASK); 143 offs *= 4; 144 target = (instr + offs); 145 start = (uint32_t *)symval->value; 146 if (target >= limit || target < start) 147 break; 148 } 149 } 150 151 if (instr >= limit) 152 return (0); 153 154 /* 155 * We have a winner! 156 */ 157 fbt = malloc(sizeof (fbt_probe_t), M_FBT, M_WAITOK | M_ZERO); 158 fbt->fbtp_name = name; 159 if (retfbt == NULL) { 160 fbt->fbtp_id = dtrace_probe_create(fbt_id, modname, 161 name, FBT_RETURN, 3, fbt); 162 } else { 163 retfbt->fbtp_probenext = fbt; 164 fbt->fbtp_id = retfbt->fbtp_id; 165 } 166 retfbt = fbt; 167 168 fbt->fbtp_patchpoint = instr; 169 fbt->fbtp_ctl = lf; 170 fbt->fbtp_loadcnt = lf->loadcnt; 171 fbt->fbtp_symindx = symindx; 172 if ((*instr & B_MASK) == B_INSTR) 173 fbt->fbtp_rval = DTRACE_INVOP_B; 174 else 175 fbt->fbtp_rval = DTRACE_INVOP_RET; 176 fbt->fbtp_savedval = *instr; 177 fbt->fbtp_patchval = FBT_PATCHVAL; 178 fbt->fbtp_hashnext = fbt_probetab[FBT_ADDR2NDX(instr)]; 179 fbt_probetab[FBT_ADDR2NDX(instr)] = fbt; 180 181 lf->fbt_nentries++; 182 183 instr++; 184 goto again; 185 } 186