diff options
Diffstat (limited to 'sys/cddl/dev/dtrace/x86/instr_size.c')
-rw-r--r-- | sys/cddl/dev/dtrace/x86/instr_size.c | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/sys/cddl/dev/dtrace/x86/instr_size.c b/sys/cddl/dev/dtrace/x86/instr_size.c new file mode 100644 index 000000000000..6eea987244b1 --- /dev/null +++ b/sys/cddl/dev/dtrace/x86/instr_size.c @@ -0,0 +1,140 @@ +/* + * CDDL HEADER START + * + * The contents of this file are subject to the terms of the + * Common Development and Distribution License, Version 1.0 only + * (the "License"). You may not use this file except in compliance + * with the License. + * + * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE + * or http://www.opensolaris.org/os/licensing. + * See the License for the specific language governing permissions + * and limitations under the License. + * + * When distributing Covered Code, include this CDDL HEADER in each + * file and include the License file at usr/src/OPENSOLARIS.LICENSE. + * If applicable, add the following below this CDDL HEADER, with the + * fields enclosed by brackets "[]" replaced with your own identifying + * information: Portions Copyright [yyyy] [name of copyright owner] + * + * CDDL HEADER END + * + * $FreeBSD$ + */ +/* + * Copyright 2005 Sun Microsystems, Inc. All rights reserved. + * Use is subject to license terms. + */ + +/* Copyright (c) 1988 AT&T */ +/* All Rights Reserved */ + + +#ifdef illumos +#pragma ident "@(#)instr_size.c 1.14 05/07/08 SMI" +#endif + +#include <sys/types.h> +#include <sys/param.h> +#include <sys/proc.h> +#ifdef illumos +#include <sys/cmn_err.h> +#include <sys/archsystm.h> +#include <sys/copyops.h> +#include <vm/seg_enum.h> +#include <sys/privregs.h> +#else +#include <sys/cred.h> +#include <cddl/dev/dtrace/dtrace_cddl.h> + +typedef u_int model_t; +#define DATAMODEL_NATIVE 0 +int dtrace_instr_size(uchar_t *); +int dtrace_instr_size_isa(uchar_t *, model_t, int *); +#endif + +#include <dis_tables.h> + +/* + * This subsystem (with the minor exception of the instr_size() function) is + * is called from DTrace probe context. This imposes several requirements on + * the implementation: + * + * 1. External subsystems and functions may not be referenced. The one current + * exception is for cmn_err, but only to signal the detection of table + * errors. Assuming the tables are correct, no combination of input is to + * trigger a cmn_err call. + * + * 2. These functions can't be allowed to be traced. To prevent this, + * all functions in the probe path (everything except instr_size()) must + * have names that begin with "dtrace_". + */ + +typedef enum dis_isize { + DIS_ISIZE_INSTR, + DIS_ISIZE_OPERAND +} dis_isize_t; + + +/* + * get a byte from instruction stream + */ +static int +dtrace_dis_get_byte(void *p) +{ + int ret; + uchar_t **instr = p; + + ret = **instr; + *instr += 1; + + return (ret); +} + +/* + * Returns either the size of a given instruction, in bytes, or the size of that + * instruction's memory access (if any), depending on the value of `which'. + * If a programming error in the tables is detected, the system will panic to + * ease diagnosis. Invalid instructions will not be flagged. They will appear + * to have an instruction size between 1 and the actual size, and will be + * reported as having no memory impact. + */ +/* ARGSUSED2 */ +static int +dtrace_dis_isize(uchar_t *instr, dis_isize_t which, model_t model, int *rmindex) +{ + int sz; + dis86_t x; + uint_t mode = SIZE32; + + mode = (model == DATAMODEL_LP64) ? SIZE64 : SIZE32; + + x.d86_data = (void **)&instr; + x.d86_get_byte = dtrace_dis_get_byte; + x.d86_check_func = NULL; + + if (dtrace_disx86(&x, mode) != 0) + return (-1); + + if (which == DIS_ISIZE_INSTR) + sz = x.d86_len; /* length of the instruction */ + else + sz = x.d86_memsize; /* length of memory operand */ + + if (rmindex != NULL) + *rmindex = x.d86_rmindex; + return (sz); +} + +int +dtrace_instr_size_isa(uchar_t *instr, model_t model, int *rmindex) +{ + return (dtrace_dis_isize(instr, DIS_ISIZE_INSTR, model, rmindex)); +} + +int +dtrace_instr_size(uchar_t *instr) +{ + return (dtrace_dis_isize(instr, DIS_ISIZE_INSTR, DATAMODEL_NATIVE, + NULL)); +} |