xref: /illumos-gate/usr/src/uts/common/sys/dtrace.h (revision 0b38a8bdfd75ac6144f9d462bb38d0c1b3f0ca50)
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, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #ifndef _SYS_DTRACE_H
28 #define	_SYS_DTRACE_H
29 
30 #pragma ident	"%Z%%M%	%I%	%E% SMI"
31 
32 #ifdef	__cplusplus
33 extern "C" {
34 #endif
35 
36 /*
37  * DTrace Dynamic Tracing Software: Kernel Interfaces
38  *
39  * Note: The contents of this file are private to the implementation of the
40  * Solaris system and DTrace subsystem and are subject to change at any time
41  * without notice.  Applications and drivers using these interfaces will fail
42  * to run on future releases.  These interfaces should not be used for any
43  * purpose except those expressly outlined in dtrace(7D) and libdtrace(3LIB).
44  * Please refer to the "Solaris Dynamic Tracing Guide" for more information.
45  */
46 
47 #ifndef _ASM
48 
49 #include <sys/types.h>
50 #include <sys/modctl.h>
51 #include <sys/processor.h>
52 #include <sys/systm.h>
53 #include <sys/ctf_api.h>
54 #include <sys/cyclic.h>
55 #include <sys/int_limits.h>
56 
57 /*
58  * DTrace Universal Constants and Typedefs
59  */
60 #define	DTRACE_CPUALL		-1	/* all CPUs */
61 #define	DTRACE_IDNONE		0	/* invalid probe identifier */
62 #define	DTRACE_EPIDNONE		0	/* invalid enabled probe identifier */
63 #define	DTRACE_AGGIDNONE	0	/* invalid aggregation identifier */
64 #define	DTRACE_CACHEIDNONE	0	/* invalid predicate cache */
65 #define	DTRACE_PROVNONE		0	/* invalid provider identifier */
66 #define	DTRACE_METAPROVNONE	0	/* invalid meta-provider identifier */
67 #define	DTRACE_ARGNONE		-1	/* invalid argument index */
68 
69 #define	DTRACE_PROVNAMELEN	64
70 #define	DTRACE_MODNAMELEN	64
71 #define	DTRACE_FUNCNAMELEN	128
72 #define	DTRACE_NAMELEN		64
73 #define	DTRACE_FULLNAMELEN	(DTRACE_PROVNAMELEN + DTRACE_MODNAMELEN + \
74 				DTRACE_FUNCNAMELEN + DTRACE_NAMELEN + 4)
75 #define	DTRACE_ARGTYPELEN	128
76 
77 typedef uint32_t dtrace_id_t;		/* probe identifier */
78 typedef uint32_t dtrace_epid_t;		/* enabled probe identifier */
79 typedef uint32_t dtrace_aggid_t;	/* aggregation identifier */
80 typedef uint16_t dtrace_actkind_t;	/* action kind */
81 typedef int64_t dtrace_optval_t;	/* option value */
82 typedef uint32_t dtrace_cacheid_t;	/* predicate cache identifier */
83 
84 typedef enum dtrace_probespec {
85 	DTRACE_PROBESPEC_NONE = -1,
86 	DTRACE_PROBESPEC_PROVIDER = 0,
87 	DTRACE_PROBESPEC_MOD,
88 	DTRACE_PROBESPEC_FUNC,
89 	DTRACE_PROBESPEC_NAME
90 } dtrace_probespec_t;
91 
92 /*
93  * DTrace Intermediate Format (DIF)
94  *
95  * The following definitions describe the DTrace Intermediate Format (DIF), a
96  * a RISC-like instruction set and program encoding used to represent
97  * predicates and actions that can be bound to DTrace probes.  The constants
98  * below defining the number of available registers are suggested minimums; the
99  * compiler should use DTRACEIOC_CONF to dynamically obtain the number of
100  * registers provided by the current DTrace implementation.
101  */
102 #define	DIF_VERSION_1	1		/* DIF version 1: Solaris 10 Beta */
103 #define	DIF_VERSION_2	2		/* DIF version 2: Solaris 10 FCS */
104 #define	DIF_VERSION	DIF_VERSION_2	/* latest DIF instruction set version */
105 #define	DIF_DIR_NREGS	8		/* number of DIF integer registers */
106 #define	DIF_DTR_NREGS	8		/* number of DIF tuple registers */
107 
108 #define	DIF_OP_OR	1		/* or	r1, r2, rd */
109 #define	DIF_OP_XOR	2		/* xor	r1, r2, rd */
110 #define	DIF_OP_AND	3		/* and	r1, r2, rd */
111 #define	DIF_OP_SLL	4		/* sll	r1, r2, rd */
112 #define	DIF_OP_SRL	5		/* srl	r1, r2, rd */
113 #define	DIF_OP_SUB	6		/* sub	r1, r2, rd */
114 #define	DIF_OP_ADD	7		/* add	r1, r2, rd */
115 #define	DIF_OP_MUL	8		/* mul	r1, r2, rd */
116 #define	DIF_OP_SDIV	9		/* sdiv	r1, r2, rd */
117 #define	DIF_OP_UDIV	10		/* udiv r1, r2, rd */
118 #define	DIF_OP_SREM	11		/* srem r1, r2, rd */
119 #define	DIF_OP_UREM	12		/* urem r1, r2, rd */
120 #define	DIF_OP_NOT	13		/* not	r1, rd */
121 #define	DIF_OP_MOV	14		/* mov	r1, rd */
122 #define	DIF_OP_CMP	15		/* cmp	r1, r2 */
123 #define	DIF_OP_TST	16		/* tst  r1 */
124 #define	DIF_OP_BA	17		/* ba	label */
125 #define	DIF_OP_BE	18		/* be	label */
126 #define	DIF_OP_BNE	19		/* bne	label */
127 #define	DIF_OP_BG	20		/* bg	label */
128 #define	DIF_OP_BGU	21		/* bgu	label */
129 #define	DIF_OP_BGE	22		/* bge	label */
130 #define	DIF_OP_BGEU	23		/* bgeu	label */
131 #define	DIF_OP_BL	24		/* bl	label */
132 #define	DIF_OP_BLU	25		/* blu	label */
133 #define	DIF_OP_BLE	26		/* ble	label */
134 #define	DIF_OP_BLEU	27		/* bleu	label */
135 #define	DIF_OP_LDSB	28		/* ldsb	[r1], rd */
136 #define	DIF_OP_LDSH	29		/* ldsh	[r1], rd */
137 #define	DIF_OP_LDSW	30		/* ldsw [r1], rd */
138 #define	DIF_OP_LDUB	31		/* ldub	[r1], rd */
139 #define	DIF_OP_LDUH	32		/* lduh	[r1], rd */
140 #define	DIF_OP_LDUW	33		/* lduw	[r1], rd */
141 #define	DIF_OP_LDX	34		/* ldx	[r1], rd */
142 #define	DIF_OP_RET	35		/* ret	rd */
143 #define	DIF_OP_NOP	36		/* nop */
144 #define	DIF_OP_SETX	37		/* setx	intindex, rd */
145 #define	DIF_OP_SETS	38		/* sets strindex, rd */
146 #define	DIF_OP_SCMP	39		/* scmp	r1, r2 */
147 #define	DIF_OP_LDGA	40		/* ldga	var, ri, rd */
148 #define	DIF_OP_LDGS	41		/* ldgs var, rd */
149 #define	DIF_OP_STGS	42		/* stgs var, rs */
150 #define	DIF_OP_LDTA	43		/* ldta var, ri, rd */
151 #define	DIF_OP_LDTS	44		/* ldts var, rd */
152 #define	DIF_OP_STTS	45		/* stts var, rs */
153 #define	DIF_OP_SRA	46		/* sra	r1, r2, rd */
154 #define	DIF_OP_CALL	47		/* call	subr, rd */
155 #define	DIF_OP_PUSHTR	48		/* pushtr type, rs, rr */
156 #define	DIF_OP_PUSHTV	49		/* pushtv type, rs, rv */
157 #define	DIF_OP_POPTS	50		/* popts */
158 #define	DIF_OP_FLUSHTS	51		/* flushts */
159 #define	DIF_OP_LDGAA	52		/* ldgaa var, rd */
160 #define	DIF_OP_LDTAA	53		/* ldtaa var, rd */
161 #define	DIF_OP_STGAA	54		/* stgaa var, rs */
162 #define	DIF_OP_STTAA	55		/* sttaa var, rs */
163 #define	DIF_OP_LDLS	56		/* ldls	var, rd */
164 #define	DIF_OP_STLS	57		/* stls	var, rs */
165 #define	DIF_OP_ALLOCS	58		/* allocs r1, rd */
166 #define	DIF_OP_COPYS	59		/* copys  r1, r2, rd */
167 #define	DIF_OP_STB	60		/* stb	r1, [rd] */
168 #define	DIF_OP_STH	61		/* sth	r1, [rd] */
169 #define	DIF_OP_STW	62		/* stw	r1, [rd] */
170 #define	DIF_OP_STX	63		/* stx	r1, [rd] */
171 #define	DIF_OP_ULDSB	64		/* uldsb [r1], rd */
172 #define	DIF_OP_ULDSH	65		/* uldsh [r1], rd */
173 #define	DIF_OP_ULDSW	66		/* uldsw [r1], rd */
174 #define	DIF_OP_ULDUB	67		/* uldub [r1], rd */
175 #define	DIF_OP_ULDUH	68		/* ulduh [r1], rd */
176 #define	DIF_OP_ULDUW	69		/* ulduw [r1], rd */
177 #define	DIF_OP_ULDX	70		/* uldx  [r1], rd */
178 #define	DIF_OP_RLDSB	71		/* rldsb [r1], rd */
179 #define	DIF_OP_RLDSH	72		/* rldsh [r1], rd */
180 #define	DIF_OP_RLDSW	73		/* rldsw [r1], rd */
181 #define	DIF_OP_RLDUB	74		/* rldub [r1], rd */
182 #define	DIF_OP_RLDUH	75		/* rlduh [r1], rd */
183 #define	DIF_OP_RLDUW	76		/* rlduw [r1], rd */
184 #define	DIF_OP_RLDX	77		/* rldx  [r1], rd */
185 
186 #define	DIF_INTOFF_MAX		0xffff	/* highest integer table offset */
187 #define	DIF_STROFF_MAX		0xffff	/* highest string table offset */
188 #define	DIF_REGISTER_MAX	0xff	/* highest register number */
189 #define	DIF_VARIABLE_MAX	0xffff	/* highest variable identifier */
190 #define	DIF_SUBROUTINE_MAX	0xffff	/* highest subroutine code */
191 
192 #define	DIF_VAR_ARRAY_MIN	0x0000	/* lowest numbered array variable */
193 #define	DIF_VAR_ARRAY_UBASE	0x0080	/* lowest user-defined array */
194 #define	DIF_VAR_ARRAY_MAX	0x00ff	/* highest numbered array variable */
195 
196 #define	DIF_VAR_OTHER_MIN	0x0100	/* lowest numbered scalar or assc */
197 #define	DIF_VAR_OTHER_UBASE	0x0500	/* lowest user-defined scalar or assc */
198 #define	DIF_VAR_OTHER_MAX	0xffff	/* highest numbered scalar or assc */
199 
200 #define	DIF_VAR_ARGS		0x0000	/* arguments array */
201 #define	DIF_VAR_REGS		0x0001	/* registers array */
202 #define	DIF_VAR_UREGS		0x0002	/* user registers array */
203 #define	DIF_VAR_CURTHREAD	0x0100	/* thread pointer */
204 #define	DIF_VAR_TIMESTAMP	0x0101	/* timestamp */
205 #define	DIF_VAR_VTIMESTAMP	0x0102	/* virtual timestamp */
206 #define	DIF_VAR_IPL		0x0103	/* interrupt priority level */
207 #define	DIF_VAR_EPID		0x0104	/* enabled probe ID */
208 #define	DIF_VAR_ID		0x0105	/* probe ID */
209 #define	DIF_VAR_ARG0		0x0106	/* first argument */
210 #define	DIF_VAR_ARG1		0x0107	/* second argument */
211 #define	DIF_VAR_ARG2		0x0108	/* third argument */
212 #define	DIF_VAR_ARG3		0x0109	/* fourth argument */
213 #define	DIF_VAR_ARG4		0x010a	/* fifth argument */
214 #define	DIF_VAR_ARG5		0x010b	/* sixth argument */
215 #define	DIF_VAR_ARG6		0x010c	/* seventh argument */
216 #define	DIF_VAR_ARG7		0x010d	/* eighth argument */
217 #define	DIF_VAR_ARG8		0x010e	/* ninth argument */
218 #define	DIF_VAR_ARG9		0x010f	/* tenth argument */
219 #define	DIF_VAR_STACKDEPTH	0x0110	/* stack depth */
220 #define	DIF_VAR_CALLER		0x0111	/* caller */
221 #define	DIF_VAR_PROBEPROV	0x0112	/* probe provider */
222 #define	DIF_VAR_PROBEMOD	0x0113	/* probe module */
223 #define	DIF_VAR_PROBEFUNC	0x0114	/* probe function */
224 #define	DIF_VAR_PROBENAME	0x0115	/* probe name */
225 #define	DIF_VAR_PID		0x0116	/* process ID */
226 #define	DIF_VAR_TID		0x0117	/* (per-process) thread ID */
227 #define	DIF_VAR_EXECNAME	0x0118	/* name of executable */
228 #define	DIF_VAR_ZONENAME	0x0119	/* zone name associated with process */
229 #define	DIF_VAR_WALLTIMESTAMP	0x011a	/* wall-clock timestamp */
230 #define	DIF_VAR_USTACKDEPTH	0x011b	/* user-land stack depth */
231 
232 #define	DIF_SUBR_RAND			0
233 #define	DIF_SUBR_MUTEX_OWNED		1
234 #define	DIF_SUBR_MUTEX_OWNER		2
235 #define	DIF_SUBR_MUTEX_TYPE_ADAPTIVE	3
236 #define	DIF_SUBR_MUTEX_TYPE_SPIN	4
237 #define	DIF_SUBR_RW_READ_HELD		5
238 #define	DIF_SUBR_RW_WRITE_HELD		6
239 #define	DIF_SUBR_RW_ISWRITER		7
240 #define	DIF_SUBR_COPYIN			8
241 #define	DIF_SUBR_COPYINSTR		9
242 #define	DIF_SUBR_SPECULATION		10
243 #define	DIF_SUBR_PROGENYOF		11
244 #define	DIF_SUBR_STRLEN			12
245 #define	DIF_SUBR_COPYOUT		13
246 #define	DIF_SUBR_COPYOUTSTR		14
247 #define	DIF_SUBR_ALLOCA			15
248 #define	DIF_SUBR_BCOPY			16
249 #define	DIF_SUBR_COPYINTO		17
250 #define	DIF_SUBR_MSGDSIZE		18
251 #define	DIF_SUBR_MSGSIZE		19
252 #define	DIF_SUBR_GETMAJOR		20
253 #define	DIF_SUBR_GETMINOR		21
254 #define	DIF_SUBR_DDI_PATHNAME		22
255 #define	DIF_SUBR_STRJOIN		23
256 #define	DIF_SUBR_LLTOSTR		24
257 #define	DIF_SUBR_BASENAME		25
258 #define	DIF_SUBR_DIRNAME		26
259 #define	DIF_SUBR_CLEANPATH		27
260 #define	DIF_SUBR_STRCHR			28
261 #define	DIF_SUBR_STRRCHR		29
262 #define	DIF_SUBR_STRSTR			30
263 #define	DIF_SUBR_STRTOK			31
264 #define	DIF_SUBR_SUBSTR			32
265 #define	DIF_SUBR_INDEX			33
266 #define	DIF_SUBR_RINDEX			34
267 
268 #define	DIF_SUBR_MAX			34	/* max subroutine value */
269 
270 typedef uint32_t dif_instr_t;
271 
272 #define	DIF_INSTR_OP(i)			(((i) >> 24) & 0xff)
273 #define	DIF_INSTR_R1(i)			(((i) >> 16) & 0xff)
274 #define	DIF_INSTR_R2(i)			(((i) >>  8) & 0xff)
275 #define	DIF_INSTR_RD(i)			((i) & 0xff)
276 #define	DIF_INSTR_RS(i)			((i) & 0xff)
277 #define	DIF_INSTR_LABEL(i)		((i) & 0xffffff)
278 #define	DIF_INSTR_VAR(i)		(((i) >>  8) & 0xffff)
279 #define	DIF_INSTR_INTEGER(i)		(((i) >>  8) & 0xffff)
280 #define	DIF_INSTR_STRING(i)		(((i) >>  8) & 0xffff)
281 #define	DIF_INSTR_SUBR(i)		(((i) >>  8) & 0xffff)
282 #define	DIF_INSTR_TYPE(i)		(((i) >> 16) & 0xff)
283 
284 #define	DIF_INSTR_FMT(op, r1, r2, d) \
285 	(((op) << 24) | ((r1) << 16) | ((r2) << 8) | (d))
286 
287 #define	DIF_INSTR_NOT(r1, d)		(DIF_INSTR_FMT(DIF_OP_NOT, r1, 0, d))
288 #define	DIF_INSTR_MOV(r1, d)		(DIF_INSTR_FMT(DIF_OP_MOV, r1, 0, d))
289 #define	DIF_INSTR_CMP(op, r1, r2)	(DIF_INSTR_FMT(op, r1, r2, 0))
290 #define	DIF_INSTR_TST(r1)		(DIF_INSTR_FMT(DIF_OP_TST, r1, 0, 0))
291 #define	DIF_INSTR_BRANCH(op, label)	(((op) << 24) | (label))
292 #define	DIF_INSTR_LOAD(op, r1, d)	(DIF_INSTR_FMT(op, r1, 0, d))
293 #define	DIF_INSTR_STORE(op, r1, d)	(DIF_INSTR_FMT(op, r1, 0, d))
294 #define	DIF_INSTR_SETX(i, d)		((DIF_OP_SETX << 24) | ((i) << 8) | (d))
295 #define	DIF_INSTR_SETS(s, d)		((DIF_OP_SETS << 24) | ((s) << 8) | (d))
296 #define	DIF_INSTR_RET(d)		(DIF_INSTR_FMT(DIF_OP_RET, 0, 0, d))
297 #define	DIF_INSTR_NOP			(DIF_OP_NOP << 24)
298 #define	DIF_INSTR_LDA(op, v, r, d)	(DIF_INSTR_FMT(op, v, r, d))
299 #define	DIF_INSTR_LDV(op, v, d)		(((op) << 24) | ((v) << 8) | (d))
300 #define	DIF_INSTR_STV(op, v, rs)	(((op) << 24) | ((v) << 8) | (rs))
301 #define	DIF_INSTR_CALL(s, d)		((DIF_OP_CALL << 24) | ((s) << 8) | (d))
302 #define	DIF_INSTR_PUSHTS(op, t, r2, rs)	(DIF_INSTR_FMT(op, t, r2, rs))
303 #define	DIF_INSTR_POPTS			(DIF_OP_POPTS << 24)
304 #define	DIF_INSTR_FLUSHTS		(DIF_OP_FLUSHTS << 24)
305 #define	DIF_INSTR_ALLOCS(r1, d)		(DIF_INSTR_FMT(DIF_OP_ALLOCS, r1, 0, d))
306 #define	DIF_INSTR_COPYS(r1, r2, d)	(DIF_INSTR_FMT(DIF_OP_COPYS, r1, r2, d))
307 
308 #define	DIF_REG_R0	0		/* %r0 is always set to zero */
309 
310 /*
311  * A DTrace Intermediate Format Type (DIF Type) is used to represent the types
312  * of variables, function and associative array arguments, and the return type
313  * for each DIF object (shown below).  It contains a description of the type,
314  * its size in bytes, and a module identifier.
315  */
316 typedef struct dtrace_diftype {
317 	uint8_t dtdt_kind;		/* type kind (see below) */
318 	uint8_t dtdt_ckind;		/* type kind in CTF */
319 	uint8_t dtdt_flags;		/* type flags (see below) */
320 	uint8_t dtdt_pad;		/* reserved for future use */
321 	uint32_t dtdt_size;		/* type size in bytes (unless string) */
322 } dtrace_diftype_t;
323 
324 #define	DIF_TYPE_CTF		0	/* type is a CTF type */
325 #define	DIF_TYPE_STRING		1	/* type is a D string */
326 
327 #define	DIF_TF_BYREF		0x1	/* type is passed by reference */
328 
329 /*
330  * A DTrace Intermediate Format variable record is used to describe each of the
331  * variables referenced by a given DIF object.  It contains an integer variable
332  * identifier along with variable scope and properties, as shown below.  The
333  * size of this structure must be sizeof (int) aligned.
334  */
335 typedef struct dtrace_difv {
336 	uint32_t dtdv_name;		/* variable name index in dtdo_strtab */
337 	uint32_t dtdv_id;		/* variable reference identifier */
338 	uint8_t dtdv_kind;		/* variable kind (see below) */
339 	uint8_t dtdv_scope;		/* variable scope (see below) */
340 	uint16_t dtdv_flags;		/* variable flags (see below) */
341 	dtrace_diftype_t dtdv_type;	/* variable type (see above) */
342 } dtrace_difv_t;
343 
344 #define	DIFV_KIND_ARRAY		0	/* variable is an array of quantities */
345 #define	DIFV_KIND_SCALAR	1	/* variable is a scalar quantity */
346 
347 #define	DIFV_SCOPE_GLOBAL	0	/* variable has global scope */
348 #define	DIFV_SCOPE_THREAD	1	/* variable has thread scope */
349 #define	DIFV_SCOPE_LOCAL	2	/* variable has local scope */
350 
351 #define	DIFV_F_REF		0x1	/* variable is referenced by DIFO */
352 #define	DIFV_F_MOD		0x2	/* variable is written by DIFO */
353 
354 /*
355  * DTrace Actions
356  *
357  * The upper byte determines the class of the action; the low bytes determines
358  * the specific action within that class.  The classes of actions are as
359  * follows:
360  *
361  *   [ no class ]                  <= May record process- or kernel-related data
362  *   DTRACEACT_PROC                <= Only records process-related data
363  *   DTRACEACT_PROC_DESTRUCTIVE    <= Potentially destructive to processes
364  *   DTRACEACT_KERNEL              <= Only records kernel-related data
365  *   DTRACEACT_KERNEL_DESTRUCTIVE  <= Potentially destructive to the kernel
366  *   DTRACEACT_SPECULATIVE         <= Speculation-related action
367  *   DTRACEACT_AGGREGATION         <= Aggregating action
368  */
369 #define	DTRACEACT_NONE			0	/* no action */
370 #define	DTRACEACT_DIFEXPR		1	/* action is DIF expression */
371 #define	DTRACEACT_EXIT			2	/* exit() action */
372 #define	DTRACEACT_PRINTF		3	/* printf() action */
373 #define	DTRACEACT_PRINTA		4	/* printa() action */
374 #define	DTRACEACT_LIBACT		5	/* library-controlled action */
375 
376 #define	DTRACEACT_PROC			0x0100
377 #define	DTRACEACT_USTACK		(DTRACEACT_PROC + 1)
378 #define	DTRACEACT_JSTACK		(DTRACEACT_PROC + 2)
379 
380 #define	DTRACEACT_PROC_DESTRUCTIVE	0x0200
381 #define	DTRACEACT_STOP			(DTRACEACT_PROC_DESTRUCTIVE + 1)
382 #define	DTRACEACT_RAISE			(DTRACEACT_PROC_DESTRUCTIVE + 2)
383 #define	DTRACEACT_SYSTEM		(DTRACEACT_PROC_DESTRUCTIVE + 3)
384 #define	DTRACEACT_FREOPEN		(DTRACEACT_PROC_DESTRUCTIVE + 4)
385 
386 #define	DTRACEACT_PROC_CONTROL		0x0300
387 
388 #define	DTRACEACT_KERNEL		0x0400
389 #define	DTRACEACT_STACK			(DTRACEACT_KERNEL + 1)
390 
391 #define	DTRACEACT_KERNEL_DESTRUCTIVE	0x0500
392 #define	DTRACEACT_BREAKPOINT		(DTRACEACT_KERNEL_DESTRUCTIVE + 1)
393 #define	DTRACEACT_PANIC			(DTRACEACT_KERNEL_DESTRUCTIVE + 2)
394 #define	DTRACEACT_CHILL			(DTRACEACT_KERNEL_DESTRUCTIVE + 3)
395 
396 #define	DTRACEACT_SPECULATIVE		0x0600
397 #define	DTRACEACT_SPECULATE		(DTRACEACT_SPECULATIVE + 1)
398 #define	DTRACEACT_COMMIT		(DTRACEACT_SPECULATIVE + 2)
399 #define	DTRACEACT_DISCARD		(DTRACEACT_SPECULATIVE + 3)
400 
401 #define	DTRACEACT_CLASS(x)		((x) & 0xff00)
402 
403 #define	DTRACEACT_ISDESTRUCTIVE(x)	\
404 	(DTRACEACT_CLASS(x) == DTRACEACT_PROC_DESTRUCTIVE || \
405 	DTRACEACT_CLASS(x) == DTRACEACT_KERNEL_DESTRUCTIVE)
406 
407 #define	DTRACEACT_ISSPECULATIVE(x)	\
408 	(DTRACEACT_CLASS(x) == DTRACEACT_SPECULATIVE)
409 
410 #define	DTRACEACT_ISPRINTFLIKE(x)	\
411 	((x) == DTRACEACT_PRINTF || (x) == DTRACEACT_PRINTA || \
412 	(x) == DTRACEACT_SYSTEM || (x) == DTRACEACT_FREOPEN)
413 
414 /*
415  * DTrace Aggregating Actions
416  *
417  * These are functions f(x) for which the following is true:
418  *
419  *    f(f(x_0) U f(x_1) U ... U f(x_n)) = f(x_0 U x_1 U ... U x_n)
420  *
421  * where x_n is a set of arbitrary data.  Aggregating actions are in their own
422  * DTrace action class, DTTRACEACT_AGGREGATION.  The macros provided here allow
423  * for easier processing of the aggregation argument and data payload for a few
424  * aggregating actions (notably:  quantize(), lquantize(), and ustack()).
425  */
426 #define	DTRACEACT_AGGREGATION		0x0700
427 #define	DTRACEAGG_COUNT			(DTRACEACT_AGGREGATION + 1)
428 #define	DTRACEAGG_MIN			(DTRACEACT_AGGREGATION + 2)
429 #define	DTRACEAGG_MAX			(DTRACEACT_AGGREGATION + 3)
430 #define	DTRACEAGG_AVG			(DTRACEACT_AGGREGATION + 4)
431 #define	DTRACEAGG_SUM			(DTRACEACT_AGGREGATION + 5)
432 #define	DTRACEAGG_STDDEV		(DTRACEACT_AGGREGATION + 6)
433 #define	DTRACEAGG_QUANTIZE		(DTRACEACT_AGGREGATION + 7)
434 #define	DTRACEAGG_LQUANTIZE		(DTRACEACT_AGGREGATION + 8)
435 
436 #define	DTRACEACT_ISAGG(x)		\
437 	(DTRACEACT_CLASS(x) == DTRACEACT_AGGREGATION)
438 
439 #define	DTRACE_QUANTIZE_NBUCKETS	\
440 	(((sizeof (uint64_t) * NBBY) - 1) * 2 + 1)
441 
442 #define	DTRACE_QUANTIZE_ZEROBUCKET	((sizeof (uint64_t) * NBBY) - 1)
443 
444 #define	DTRACE_QUANTIZE_BUCKETVAL(buck)					\
445 	(int64_t)((buck) < DTRACE_QUANTIZE_ZEROBUCKET ?			\
446 	-(1LL << (DTRACE_QUANTIZE_ZEROBUCKET - 1 - (buck))) :		\
447 	(buck) == DTRACE_QUANTIZE_ZEROBUCKET ? 0 :			\
448 	1LL << ((buck) - DTRACE_QUANTIZE_ZEROBUCKET - 1))
449 
450 #define	DTRACE_LQUANTIZE_STEPSHIFT		48
451 #define	DTRACE_LQUANTIZE_STEPMASK		((uint64_t)UINT16_MAX << 48)
452 #define	DTRACE_LQUANTIZE_LEVELSHIFT		32
453 #define	DTRACE_LQUANTIZE_LEVELMASK		((uint64_t)UINT16_MAX << 32)
454 #define	DTRACE_LQUANTIZE_BASESHIFT		0
455 #define	DTRACE_LQUANTIZE_BASEMASK		UINT32_MAX
456 
457 #define	DTRACE_LQUANTIZE_STEP(x)		\
458 	(uint16_t)(((x) & DTRACE_LQUANTIZE_STEPMASK) >> \
459 	DTRACE_LQUANTIZE_STEPSHIFT)
460 
461 #define	DTRACE_LQUANTIZE_LEVELS(x)		\
462 	(uint16_t)(((x) & DTRACE_LQUANTIZE_LEVELMASK) >> \
463 	DTRACE_LQUANTIZE_LEVELSHIFT)
464 
465 #define	DTRACE_LQUANTIZE_BASE(x)		\
466 	(int32_t)(((x) & DTRACE_LQUANTIZE_BASEMASK) >> \
467 	DTRACE_LQUANTIZE_BASESHIFT)
468 
469 #define	DTRACE_USTACK_NFRAMES(x)	(uint32_t)((x) & UINT32_MAX)
470 #define	DTRACE_USTACK_STRSIZE(x)	(uint32_t)((x) >> 32)
471 #define	DTRACE_USTACK_ARG(x, y)		\
472 	((((uint64_t)(y)) << 32) | ((x) & UINT32_MAX))
473 
474 #ifndef _LP64
475 #ifndef _LITTLE_ENDIAN
476 #define	DTRACE_PTR(type, name)	uint32_t name##pad; type *name
477 #else
478 #define	DTRACE_PTR(type, name)	type *name; uint32_t name##pad
479 #endif
480 #else
481 #define	DTRACE_PTR(type, name)	type *name
482 #endif
483 
484 /*
485  * DTrace Object Format (DOF)
486  *
487  * DTrace programs can be persistently encoded in the DOF format so that they
488  * may be embedded in other programs (for example, in an ELF file) or in the
489  * dtrace driver configuration file for use in anonymous tracing.  The DOF
490  * format is versioned and extensible so that it can be revised and so that
491  * internal data structures can be modified or extended compatibly.  All DOF
492  * structures use fixed-size types, so the 32-bit and 64-bit representations
493  * are identical and consumers can use either data model transparently.
494  *
495  * The file layout is structured as follows:
496  *
497  * +---------------+-------------------+----- ... ----+---- ... ------+
498  * |   dof_hdr_t   |  dof_sec_t[ ... ] |   loadable   | non-loadable  |
499  * | (file header) | (section headers) | section data | section data  |
500  * +---------------+-------------------+----- ... ----+---- ... ------+
501  * |<------------ dof_hdr.dofh_loadsz --------------->|               |
502  * |<------------ dof_hdr.dofh_filesz ------------------------------->|
503  *
504  * The file header stores meta-data including a magic number, data model for
505  * the instrumentation, data encoding, and properties of the DIF code within.
506  * The header describes its own size and the size of the section headers.  By
507  * convention, an array of section headers follows the file header, and then
508  * the data for all loadable sections and unloadable sections.  This permits
509  * consumer code to easily download the headers and all loadable data into the
510  * DTrace driver in one contiguous chunk, omitting other extraneous sections.
511  *
512  * The section headers describe the size, offset, alignment, and section type
513  * for each section.  Sections are described using a set of #defines that tell
514  * the consumer what kind of data is expected.  Sections can contain links to
515  * other sections by storing a dof_secidx_t, an index into the section header
516  * array, inside of the section data structures.  The section header includes
517  * an entry size so that sections with data arrays can grow their structures.
518  *
519  * The DOF data itself can contain many snippets of DIF (i.e. >1 DIFOs), which
520  * are represented themselves as a collection of related DOF sections.  This
521  * permits us to change the set of sections associated with a DIFO over time,
522  * and also permits us to encode DIFOs that contain different sets of sections.
523  * When a DOF section wants to refer to a DIFO, it stores the dof_secidx_t of a
524  * section of type DOF_SECT_DIFOHDR.  This section's data is then an array of
525  * dof_secidx_t's which in turn denote the sections associated with this DIFO.
526  *
527  * This loose coupling of the file structure (header and sections) to the
528  * structure of the DTrace program itself (ECB descriptions, action
529  * descriptions, and DIFOs) permits activities such as relocation processing
530  * to occur in a single pass without having to understand D program structure.
531  *
532  * Finally, strings are always stored in ELF-style string tables along with a
533  * string table section index and string table offset.  Therefore strings in
534  * DOF are always arbitrary-length and not bound to the current implementation.
535  */
536 
537 #define	DOF_ID_SIZE	16	/* total size of dofh_ident[] in bytes */
538 
539 typedef struct dof_hdr {
540 	uint8_t dofh_ident[DOF_ID_SIZE]; /* identification bytes (see below) */
541 	uint32_t dofh_flags;		/* file attribute flags (if any) */
542 	uint32_t dofh_hdrsize;		/* size of file header in bytes */
543 	uint32_t dofh_secsize;		/* size of section header in bytes */
544 	uint32_t dofh_secnum;		/* number of section headers */
545 	uint64_t dofh_secoff;		/* file offset of section headers */
546 	uint64_t dofh_loadsz;		/* file size of loadable portion */
547 	uint64_t dofh_filesz;		/* file size of entire DOF file */
548 	uint64_t dofh_pad;		/* reserved for future use */
549 } dof_hdr_t;
550 
551 #define	DOF_ID_MAG0	0	/* first byte of magic number */
552 #define	DOF_ID_MAG1	1	/* second byte of magic number */
553 #define	DOF_ID_MAG2	2	/* third byte of magic number */
554 #define	DOF_ID_MAG3	3	/* fourth byte of magic number */
555 #define	DOF_ID_MODEL	4	/* DOF data model (see below) */
556 #define	DOF_ID_ENCODING	5	/* DOF data encoding (see below) */
557 #define	DOF_ID_VERSION	6	/* DOF file format major version (see below) */
558 #define	DOF_ID_DIFVERS	7	/* DIF instruction set version */
559 #define	DOF_ID_DIFIREG	8	/* DIF integer registers used by compiler */
560 #define	DOF_ID_DIFTREG	9	/* DIF tuple registers used by compiler */
561 #define	DOF_ID_PAD	10	/* start of padding bytes (all zeroes) */
562 
563 #define	DOF_MAG_MAG0	0x7F	/* DOF_ID_MAG[0-3] */
564 #define	DOF_MAG_MAG1	'D'
565 #define	DOF_MAG_MAG2	'O'
566 #define	DOF_MAG_MAG3	'F'
567 
568 #define	DOF_MAG_STRING	"\177DOF"
569 #define	DOF_MAG_STRLEN	4
570 
571 #define	DOF_MODEL_NONE	0	/* DOF_ID_MODEL */
572 #define	DOF_MODEL_ILP32	1
573 #define	DOF_MODEL_LP64	2
574 
575 #ifdef _LP64
576 #define	DOF_MODEL_NATIVE	DOF_MODEL_LP64
577 #else
578 #define	DOF_MODEL_NATIVE	DOF_MODEL_ILP32
579 #endif
580 
581 #define	DOF_ENCODE_NONE	0	/* DOF_ID_ENCODING */
582 #define	DOF_ENCODE_LSB	1
583 #define	DOF_ENCODE_MSB	2
584 
585 #ifdef _BIG_ENDIAN
586 #define	DOF_ENCODE_NATIVE	DOF_ENCODE_MSB
587 #else
588 #define	DOF_ENCODE_NATIVE	DOF_ENCODE_LSB
589 #endif
590 
591 #define	DOF_VERSION_1	1	/* DOF_ID_VERSION */
592 #define	DOF_VERSION	DOF_VERSION_1
593 
594 #define	DOF_FL_VALID	0	/* mask of all valid dofh_flags bits */
595 
596 typedef uint32_t dof_secidx_t;	/* section header table index type */
597 typedef uint32_t dof_stridx_t;	/* string table index type */
598 
599 #define	DOF_SECIDX_NONE	(-1U)	/* null value for section indices */
600 #define	DOF_STRIDX_NONE	(-1U)	/* null value for string indices */
601 
602 typedef struct dof_sec {
603 	uint32_t dofs_type;	/* section type (see below) */
604 	uint32_t dofs_align;	/* section data memory alignment */
605 	uint32_t dofs_flags;	/* section flags (if any) */
606 	uint32_t dofs_entsize;	/* size of section entry (if table) */
607 	uint64_t dofs_offset;	/* offset of section data within file */
608 	uint64_t dofs_size;	/* size of section data in bytes */
609 } dof_sec_t;
610 
611 #define	DOF_SECT_NONE		0	/* null section */
612 #define	DOF_SECT_COMMENTS	1	/* compiler comments */
613 #define	DOF_SECT_SOURCE		2	/* D program source code */
614 #define	DOF_SECT_ECBDESC	3	/* dof_ecbdesc_t */
615 #define	DOF_SECT_PROBEDESC	4	/* dof_probedesc_t */
616 #define	DOF_SECT_ACTDESC	5	/* dof_actdesc_t array */
617 #define	DOF_SECT_DIFOHDR	6	/* dof_difohdr_t (variable length) */
618 #define	DOF_SECT_DIF		7	/* uint32_t array of byte code */
619 #define	DOF_SECT_STRTAB		8	/* string table */
620 #define	DOF_SECT_VARTAB		9	/* dtrace_difv_t array */
621 #define	DOF_SECT_RELTAB		10	/* dof_relodesc_t array */
622 #define	DOF_SECT_TYPTAB		11	/* dtrace_diftype_t array */
623 #define	DOF_SECT_URELHDR	12	/* dof_relohdr_t (user relocations) */
624 #define	DOF_SECT_KRELHDR	13	/* dof_relohdr_t (kernel relocations) */
625 #define	DOF_SECT_OPTDESC	14	/* dof_optdesc_t array */
626 #define	DOF_SECT_PROVIDER	15	/* dof_provider_t */
627 #define	DOF_SECT_PROBES		16	/* dof_probe_t array */
628 #define	DOF_SECT_PRARGS		17	/* uint8_t array (probe arg mappings) */
629 #define	DOF_SECT_PROFFS		18	/* uint32_t array (probe arg offsets) */
630 #define	DOF_SECT_INTTAB		19	/* uint64_t array */
631 #define	DOF_SECT_UTSNAME	20	/* struct utsname */
632 
633 #define	DOF_SECF_LOAD		1	/* section should be loaded */
634 
635 typedef struct dof_ecbdesc {
636 	dof_secidx_t dofe_probes;	/* link to DOF_SECT_PROBEDESC */
637 	dof_secidx_t dofe_pred;		/* link to DOF_SECT_DIFOHDR */
638 	dof_secidx_t dofe_actions;	/* link to DOF_SECT_ACTDESC */
639 	uint32_t dofe_pad;		/* reserved for future use */
640 	uint64_t dofe_uarg;		/* user-supplied library argument */
641 } dof_ecbdesc_t;
642 
643 typedef struct dof_probedesc {
644 	dof_secidx_t dofp_strtab;	/* link to DOF_SECT_STRTAB section */
645 	dof_stridx_t dofp_provider;	/* provider string */
646 	dof_stridx_t dofp_mod;		/* module string */
647 	dof_stridx_t dofp_func;		/* function string */
648 	dof_stridx_t dofp_name;		/* name string */
649 	uint32_t dofp_id;		/* probe identifier (or zero) */
650 } dof_probedesc_t;
651 
652 typedef struct dof_actdesc {
653 	dof_secidx_t dofa_difo;		/* link to DOF_SECT_DIFOHDR */
654 	dof_secidx_t dofa_strtab;	/* link to DOF_SECT_STRTAB section */
655 	uint32_t dofa_kind;		/* action kind (DTRACEACT_* constant) */
656 	uint32_t dofa_ntuple;		/* number of subsequent tuple actions */
657 	uint64_t dofa_arg;		/* kind-specific argument */
658 	uint64_t dofa_uarg;		/* user-supplied argument */
659 } dof_actdesc_t;
660 
661 typedef struct dof_difohdr {
662 	dtrace_diftype_t dofd_rtype;	/* return type for this fragment */
663 	dof_secidx_t dofd_links[1];	/* variable length array of indices */
664 } dof_difohdr_t;
665 
666 typedef struct dof_relohdr {
667 	dof_secidx_t dofr_strtab;	/* link to DOF_SECT_STRTAB for names */
668 	dof_secidx_t dofr_relsec;	/* link to DOF_SECT_RELTAB for relos */
669 	dof_secidx_t dofr_tgtsec;	/* link to section we are relocating */
670 } dof_relohdr_t;
671 
672 typedef struct dof_relodesc {
673 	dof_stridx_t dofr_name;		/* string name of relocation symbol */
674 	uint32_t dofr_type;		/* relo type (DOF_RELO_* constant) */
675 	uint64_t dofr_offset;		/* byte offset for relocation */
676 	uint64_t dofr_data;		/* additional type-specific data */
677 } dof_relodesc_t;
678 
679 #define	DOF_RELO_NONE	0		/* empty relocation entry */
680 #define	DOF_RELO_SETX	1		/* relocate setx value */
681 
682 typedef struct dof_optdesc {
683 	uint32_t dofo_option;		/* option identifier */
684 	dof_secidx_t dofo_strtab;	/* string table, if string option */
685 	uint64_t dofo_value;		/* option value or string index */
686 } dof_optdesc_t;
687 
688 typedef uint32_t dof_attr_t;		/* encoded stability attributes */
689 
690 #define	DOF_ATTR(n, d, c)	(((n) << 24) | ((d) << 16) | ((c) << 8))
691 #define	DOF_ATTR_NAME(a)	(((a) >> 24) & 0xff)
692 #define	DOF_ATTR_DATA(a)	(((a) >> 16) & 0xff)
693 #define	DOF_ATTR_CLASS(a)	(((a) >>  8) & 0xff)
694 
695 typedef struct dof_provider {
696 	dof_secidx_t dofpv_strtab;	/* link to DOF_SECT_STRTAB section */
697 	dof_secidx_t dofpv_probes;	/* link to DOF_SECT_PROBES section */
698 	dof_secidx_t dofpv_prargs;	/* link to DOF_SECT_PRARGS section */
699 	dof_secidx_t dofpv_proffs;	/* link to DOF_SECT_PROFFS section */
700 	dof_stridx_t dofpv_name;	/* provider name string */
701 	dof_attr_t dofpv_provattr;	/* provider attributes */
702 	dof_attr_t dofpv_modattr;	/* module attributes */
703 	dof_attr_t dofpv_funcattr;	/* function attributes */
704 	dof_attr_t dofpv_nameattr;	/* name attributes */
705 	dof_attr_t dofpv_argsattr;	/* args attributes */
706 } dof_provider_t;
707 
708 typedef struct dof_probe {
709 	uint64_t dofpr_addr;		/* probe base address or offset */
710 	dof_stridx_t dofpr_func;	/* probe function string */
711 	dof_stridx_t dofpr_name;	/* probe name string */
712 	dof_stridx_t dofpr_nargv;	/* native argument type strings */
713 	dof_stridx_t dofpr_xargv;	/* translated argument type strings */
714 	uint32_t dofpr_argidx;		/* index of first argument mapping */
715 	uint32_t dofpr_offidx;		/* index of first offset entry */
716 	uint8_t dofpr_nargc;		/* native argument count */
717 	uint8_t dofpr_xargc;		/* translated argument count */
718 	uint16_t dofpr_noffs;		/* number of offset entries for probe */
719 	uint32_t dofpr_pad;		/* reserved for future use */
720 } dof_probe_t;
721 
722 /*
723  * DTrace Intermediate Format Object (DIFO)
724  *
725  * A DIFO is used to store the compiled DIF for a D expression, its return
726  * type, and its string and variable tables.  The string table is a single
727  * buffer of character data into which sets instructions and variable
728  * references can reference strings using a byte offset.  The variable table
729  * is an array of dtrace_difv_t structures that describe the name and type of
730  * each variable and the id used in the DIF code.  This structure is described
731  * above in the DIF section of this header file.  The DIFO is used at both
732  * user-level (in the library) and in the kernel, but the structure is never
733  * passed between the two: the DOF structures form the only interface.  As a
734  * result, the definition can change depending on the presence of _KERNEL.
735  */
736 typedef struct dtrace_difo {
737 	dif_instr_t *dtdo_buf;		/* instruction buffer */
738 	uint64_t *dtdo_inttab;		/* integer table (optional) */
739 	char *dtdo_strtab;		/* string table (optional) */
740 	dtrace_difv_t *dtdo_vartab;	/* variable table (optional) */
741 	uint_t dtdo_len;		/* length of instruction buffer */
742 	uint_t dtdo_intlen;		/* length of integer table */
743 	uint_t dtdo_strlen;		/* length of string table */
744 	uint_t dtdo_varlen;		/* length of variable table */
745 	dtrace_diftype_t dtdo_rtype;	/* return type */
746 	uint_t dtdo_refcnt;		/* owner reference count */
747 	uint_t dtdo_destructive;	/* invokes destructive subroutines */
748 #ifndef _KERNEL
749 	dof_relodesc_t *dtdo_kreltab;	/* kernel relocations */
750 	dof_relodesc_t *dtdo_ureltab;	/* user relocations */
751 	uint32_t dtdo_krelen;		/* length of krelo table */
752 	uint32_t dtdo_urelen;		/* length of urelo table */
753 #endif
754 } dtrace_difo_t;
755 
756 /*
757  * DTrace Enabling Description Structures
758  *
759  * When DTrace is tracking the description of a DTrace enabling entity (probe,
760  * predicate, action, ECB, record, etc.), it does so in a description
761  * structure.  These structures all end in "desc", and are used at both
762  * user-level and in the kernel -- but (with the exception of
763  * dtrace_probedesc_t) they are never passed between them.  Typically,
764  * user-level will use the description structures when assembling an enabling.
765  * It will then distill those description structures into a DOF object (see
766  * above), and send it into the kernel.  The kernel will again use the
767  * description structures to create a description of the enabling as it reads
768  * the DOF.  When the description is complete, the enabling will be actually
769  * created -- turning it into the structures that represent the enabling
770  * instead of merely describing it.  Not surprisingly, the description
771  * structures bear a strong resemblance to the DOF structures that act as their
772  * conduit.
773  */
774 struct dtrace_predicate;
775 
776 typedef struct dtrace_probedesc {
777 	dtrace_id_t dtpd_id;			/* probe identifier */
778 	char dtpd_provider[DTRACE_PROVNAMELEN]; /* probe provider name */
779 	char dtpd_mod[DTRACE_MODNAMELEN];	/* probe module name */
780 	char dtpd_func[DTRACE_FUNCNAMELEN];	/* probe function name */
781 	char dtpd_name[DTRACE_NAMELEN];		/* probe name */
782 } dtrace_probedesc_t;
783 
784 typedef struct dtrace_repldesc {
785 	dtrace_probedesc_t dtrpd_match;		/* probe descr. to match */
786 	dtrace_probedesc_t dtrpd_create;	/* probe descr. to create */
787 } dtrace_repldesc_t;
788 
789 typedef struct dtrace_preddesc {
790 	dtrace_difo_t *dtpdd_difo;		/* pointer to DIF object */
791 	struct dtrace_predicate *dtpdd_predicate; /* pointer to predicate */
792 } dtrace_preddesc_t;
793 
794 typedef struct dtrace_actdesc {
795 	dtrace_difo_t *dtad_difo;		/* pointer to DIF object */
796 	struct dtrace_actdesc *dtad_next;	/* next action */
797 	dtrace_actkind_t dtad_kind;		/* kind of action */
798 	uint32_t dtad_ntuple;			/* number in tuple */
799 	uint64_t dtad_arg;			/* action argument */
800 	uint64_t dtad_uarg;			/* user argument */
801 	int dtad_refcnt;			/* reference count */
802 } dtrace_actdesc_t;
803 
804 typedef struct dtrace_ecbdesc {
805 	dtrace_actdesc_t *dted_action;		/* action description(s) */
806 	dtrace_preddesc_t dted_pred;		/* predicate description */
807 	dtrace_probedesc_t dted_probe;		/* probe description */
808 	uint64_t dted_uarg;			/* library argument */
809 	int dted_refcnt;			/* reference count */
810 } dtrace_ecbdesc_t;
811 
812 /*
813  * DTrace Metadata Description Structures
814  *
815  * DTrace separates the trace data stream from the metadata stream.  The only
816  * metadata tokens placed in the data stream are enabled probe identifiers
817  * (EPIDs) or (in the case of aggregations) aggregation identifiers.  In order
818  * to determine the structure of the data, DTrace consumers pass the token to
819  * the kernel, and receive in return a corresponding description of the enabled
820  * probe (via the dtrace_eprobedesc structure) or the aggregation (via the
821  * dtrace_aggdesc structure).  Both of these structures are expressed in terms
822  * of record descriptions (via the dtrace_recdesc structure) that describe the
823  * exact structure of the data.  Some record descriptions may also contain a
824  * format identifier; this additional bit of metadata can be retrieved from the
825  * kernel, for which a format description is returned via the dtrace_fmtdesc
826  * structure.  Note that all four of these structures must be bitness-neutral
827  * to allow for a 32-bit DTrace consumer on a 64-bit kernel.
828  */
829 typedef struct dtrace_recdesc {
830 	dtrace_actkind_t dtrd_action;		/* kind of action */
831 	uint32_t dtrd_size;			/* size of record */
832 	uint32_t dtrd_offset;			/* offset in ECB's data */
833 	uint16_t dtrd_alignment;		/* required alignment */
834 	uint16_t dtrd_format;			/* format, if any */
835 	uint64_t dtrd_arg;			/* action argument */
836 	uint64_t dtrd_uarg;			/* user argument */
837 } dtrace_recdesc_t;
838 
839 typedef struct dtrace_eprobedesc {
840 	dtrace_epid_t dtepd_epid;		/* enabled probe ID */
841 	dtrace_id_t dtepd_probeid;		/* probe ID */
842 	uint64_t dtepd_uarg;			/* library argument */
843 	uint32_t dtepd_size;			/* total size */
844 	int dtepd_nrecs;			/* number of records */
845 	dtrace_recdesc_t dtepd_rec[1];		/* records themselves */
846 } dtrace_eprobedesc_t;
847 
848 typedef struct dtrace_aggdesc {
849 	DTRACE_PTR(char, dtagd_name);		/* not filled in by kernel */
850 	int dtagd_flags;			/* not filled in by kernel */
851 	dtrace_aggid_t dtagd_id;		/* aggregation ID */
852 	dtrace_epid_t dtagd_epid;		/* enabled probe ID */
853 	uint32_t dtagd_size;			/* size in bytes */
854 	int dtagd_nrecs;			/* number of records */
855 	uint32_t dtagd_pad;			/* explicit padding */
856 	dtrace_recdesc_t dtagd_rec[1];		/* record descriptions */
857 } dtrace_aggdesc_t;
858 
859 typedef struct dtrace_fmtdesc {
860 	DTRACE_PTR(char, dtfd_string);		/* format string */
861 	int dtfd_length;			/* length of format string */
862 	uint16_t dtfd_format;			/* format identifier */
863 } dtrace_fmtdesc_t;
864 
865 #define	DTRACE_SIZEOF_EPROBEDESC(desc)				\
866 	(sizeof (dtrace_eprobedesc_t) + ((desc)->dtepd_nrecs ?	\
867 	(((desc)->dtepd_nrecs - 1) * sizeof (dtrace_recdesc_t)) : 0))
868 
869 #define	DTRACE_SIZEOF_AGGDESC(desc)				\
870 	(sizeof (dtrace_aggdesc_t) + ((desc)->dtagd_nrecs ?	\
871 	(((desc)->dtagd_nrecs - 1) * sizeof (dtrace_recdesc_t)) : 0))
872 
873 /*
874  * DTrace Option Interface
875  *
876  * Run-time DTrace options are set and retrieved via DOF_SECT_OPTDESC sections
877  * in a DOF image.  The dof_optdesc structure contains an option identifier and
878  * an option value.  The valid option identifiers are found below; the mapping
879  * between option identifiers and option identifying strings is maintained at
880  * user-level.  Note that the value of DTRACEOPT_UNSET is such that all of the
881  * following are potentially valid option values:  all positive integers, zero
882  * and negative one.  Some options (notably "bufpolicy" and "bufresize") take
883  * predefined tokens as their values; these are defined with
884  * DTRACEOPT_{option}_{token}.
885  */
886 #define	DTRACEOPT_BUFSIZE	0	/* buffer size */
887 #define	DTRACEOPT_BUFPOLICY	1	/* buffer policy */
888 #define	DTRACEOPT_DYNVARSIZE	2	/* dynamic variable size */
889 #define	DTRACEOPT_AGGSIZE	3	/* aggregation size */
890 #define	DTRACEOPT_SPECSIZE	4	/* speculation size */
891 #define	DTRACEOPT_NSPEC		5	/* number of speculations */
892 #define	DTRACEOPT_STRSIZE	6	/* string size */
893 #define	DTRACEOPT_CLEANRATE	7	/* dynvar cleaning rate */
894 #define	DTRACEOPT_CPU		8	/* CPU to trace */
895 #define	DTRACEOPT_BUFRESIZE	9	/* buffer resizing policy */
896 #define	DTRACEOPT_GRABANON	10	/* grab anonymous state, if any */
897 #define	DTRACEOPT_FLOWINDENT	11	/* indent function entry/return */
898 #define	DTRACEOPT_QUIET		12	/* only output explicitly traced data */
899 #define	DTRACEOPT_STACKFRAMES	13	/* number of stack frames */
900 #define	DTRACEOPT_USTACKFRAMES	14	/* number of user stack frames */
901 #define	DTRACEOPT_AGGRATE	15	/* aggregation snapshot rate */
902 #define	DTRACEOPT_SWITCHRATE	16	/* buffer switching rate */
903 #define	DTRACEOPT_STATUSRATE	17	/* status rate */
904 #define	DTRACEOPT_DESTRUCTIVE	18	/* destructive actions allowed */
905 #define	DTRACEOPT_STACKINDENT	19	/* output indent for stack traces */
906 #define	DTRACEOPT_RAWBYTES	20	/* always print bytes in raw form */
907 #define	DTRACEOPT_JSTACKFRAMES	21	/* number of jstack() frames */
908 #define	DTRACEOPT_JSTACKSTRSIZE	22	/* size of jstack() string table */
909 #define	DTRACEOPT_MAX		23	/* number of options */
910 
911 #define	DTRACEOPT_UNSET		(dtrace_optval_t)-2	/* unset option */
912 
913 #define	DTRACEOPT_BUFPOLICY_RING	0	/* ring buffer */
914 #define	DTRACEOPT_BUFPOLICY_FILL	1	/* fill buffer, then stop */
915 #define	DTRACEOPT_BUFPOLICY_SWITCH	2	/* switch buffers */
916 
917 #define	DTRACEOPT_BUFRESIZE_AUTO	0	/* automatic resizing */
918 #define	DTRACEOPT_BUFRESIZE_MANUAL	1	/* manual resizing */
919 
920 /*
921  * DTrace Buffer Interface
922  *
923  * In order to get a snapshot of the principal or aggregation buffer,
924  * user-level passes a buffer description to the kernel with the dtrace_bufdesc
925  * structure.  This describes which CPU user-level is interested in, and
926  * where user-level wishes the kernel to snapshot the buffer to (the
927  * dtbd_data field).  The kernel uses the same structure to pass back some
928  * information regarding the buffer:  the size of data actually copied out, the
929  * number of drops, the number of errors, and the offset of the oldest record.
930  * If the buffer policy is a "switch" policy, taking a snapshot of the
931  * principal buffer has the additional effect of switching the active and
932  * inactive buffers.  Taking a snapshot of the aggregation buffer _always_ has
933  * the additional effect of switching the active and inactive buffers.
934  */
935 typedef struct dtrace_bufdesc {
936 	uint64_t dtbd_size;			/* size of buffer */
937 	uint32_t dtbd_cpu;			/* CPU or DTRACE_CPUALL */
938 	uint32_t dtbd_errors;			/* number of errors */
939 	uint64_t dtbd_drops;			/* number of drops */
940 	DTRACE_PTR(char, dtbd_data);		/* data */
941 	uint64_t dtbd_oldest;			/* offset of oldest record */
942 } dtrace_bufdesc_t;
943 
944 /*
945  * DTrace Status
946  *
947  * The status of DTrace is relayed via the dtrace_status structure.  This
948  * structure contains members to count drops other than the capacity drops
949  * available via the buffer interface (see above).  This consists of dynamic
950  * drops (including capacity dynamic drops, rinsing drops and dirty drops), and
951  * speculative drops (including capacity speculative drops, drops due to busy
952  * speculative buffers and drops due to unavailable speculative buffers).
953  * Additionally, the status structure contains a field to indicate the number
954  * of "fill"-policy buffers have been filled and a boolean field to indicate
955  * that exit() has been called.  If the dtst_exiting field is non-zero, no
956  * further data will be generated until tracing is stopped (at which time any
957  * enablings of the END action will be processed); if user-level sees that
958  * this field is non-zero, tracing should be stopped as soon as possible.
959  */
960 typedef struct dtrace_status {
961 	uint64_t dtst_dyndrops;			/* dynamic drops */
962 	uint64_t dtst_dyndrops_rinsing;		/* dyn drops due to rinsing */
963 	uint64_t dtst_dyndrops_dirty;		/* dyn drops due to dirty */
964 	uint64_t dtst_specdrops;		/* speculative drops */
965 	uint64_t dtst_specdrops_busy;		/* spec drops due to busy */
966 	uint64_t dtst_specdrops_unavail;	/* spec drops due to unavail */
967 	uint64_t dtst_errors;			/* total errors */
968 	uint64_t dtst_filled;			/* number of filled bufs */
969 	char dtst_killed;			/* non-zero if killed */
970 	char dtst_exiting;			/* non-zero if exit() called */
971 	char dtst_pad[6];			/* pad out to 64-bit align */
972 } dtrace_status_t;
973 
974 /*
975  * DTrace Configuration
976  *
977  * User-level may need to understand some elements of the kernel DTrace
978  * configuration in order to generate correct DIF.  This information is
979  * conveyed via the dtrace_conf structure.
980  */
981 typedef struct dtrace_conf {
982 	uint_t dtc_difversion;			/* supported DIF version */
983 	uint_t dtc_difintregs;			/* # of DIF integer registers */
984 	uint_t dtc_diftupregs;			/* # of DIF tuple registers */
985 	uint_t dtc_ctfmodel;			/* CTF data model */
986 	uint_t dtc_pad[8];			/* reserved for future use */
987 } dtrace_conf_t;
988 
989 /*
990  * DTrace Faults
991  *
992  * The constants below DTRACEFLT_LIBRARY indicate probe processing faults;
993  * constants at or above DTRACEFLT_LIBRARY indicate faults in probe
994  * postprocessing at user-level.  Probe processing faults induce an ERROR
995  * probe and are replicated in unistd.d to allow users' ERROR probes to decode
996  * the error condition using thse symbolic labels.
997  */
998 #define	DTRACEFLT_UNKNOWN		0	/* Unknown fault */
999 #define	DTRACEFLT_BADADDR		1	/* Bad address */
1000 #define	DTRACEFLT_BADALIGN		2	/* Bad alignment */
1001 #define	DTRACEFLT_ILLOP			3	/* Illegal operation */
1002 #define	DTRACEFLT_DIVZERO		4	/* Divide-by-zero */
1003 #define	DTRACEFLT_NOSCRATCH		5	/* Out of scratch space */
1004 #define	DTRACEFLT_KPRIV			6	/* Illegal kernel access */
1005 #define	DTRACEFLT_UPRIV			7	/* Illegal user access */
1006 #define	DTRACEFLT_TUPOFLOW		8	/* Tuple stack overflow */
1007 
1008 #define	DTRACEFLT_LIBRARY		1000	/* Library-level fault */
1009 
1010 /*
1011  * DTrace Argument Types
1012  *
1013  * Because it would waste both space and time, argument types do not reside
1014  * with the probe.  In order to determine argument types for args[X]
1015  * variables, the D compiler queries for argument types on a probe-by-probe
1016  * basis.  (This optimizes for the common case that arguments are either not
1017  * used or used in an untyped fashion.)  Typed arguments are specified with a
1018  * string of the type name in the dtragd_native member of the argument
1019  * description structure.  Typed arguments may be further translated to types
1020  * of greater stability; the provider indicates such a translated argument by
1021  * filling in the dtargd_xlate member with the string of the translated type.
1022  * Finally, the provider may indicate which argument value a given argument
1023  * maps to by setting the dtargd_mapping member -- allowing a single argument
1024  * to map to multiple args[X] variables.
1025  */
1026 typedef struct dtrace_argdesc {
1027 	dtrace_id_t dtargd_id;			/* probe identifier */
1028 	int dtargd_ndx;				/* arg number (-1 iff none) */
1029 	int dtargd_mapping;			/* value mapping */
1030 	char dtargd_native[DTRACE_ARGTYPELEN];	/* native type name */
1031 	char dtargd_xlate[DTRACE_ARGTYPELEN];	/* translated type name */
1032 } dtrace_argdesc_t;
1033 
1034 /*
1035  * DTrace Stability Attributes
1036  *
1037  * Each DTrace provider advertises the name and data stability of each of its
1038  * probe description components, as well as its architectural dependencies.
1039  * The D compiler can query the provider attributes (dtrace_pattr_t below) in
1040  * order to compute the properties of an input program and report them.
1041  */
1042 typedef uint8_t dtrace_stability_t;	/* stability code (see attributes(5)) */
1043 typedef uint8_t dtrace_class_t;		/* architectural dependency class */
1044 
1045 #define	DTRACE_STABILITY_INTERNAL	0	/* private to DTrace itself */
1046 #define	DTRACE_STABILITY_PRIVATE	1	/* private to Sun (see docs) */
1047 #define	DTRACE_STABILITY_OBSOLETE	2	/* scheduled for removal */
1048 #define	DTRACE_STABILITY_EXTERNAL	3	/* not controlled by Sun */
1049 #define	DTRACE_STABILITY_UNSTABLE	4	/* new or rapidly changing */
1050 #define	DTRACE_STABILITY_EVOLVING	5	/* less rapidly changing */
1051 #define	DTRACE_STABILITY_STABLE		6	/* mature interface from Sun */
1052 #define	DTRACE_STABILITY_STANDARD	7	/* industry standard */
1053 #define	DTRACE_STABILITY_MAX		7	/* maximum valid stability */
1054 
1055 #define	DTRACE_CLASS_UNKNOWN	0	/* unknown architectural dependency */
1056 #define	DTRACE_CLASS_CPU	1	/* CPU-module-specific */
1057 #define	DTRACE_CLASS_PLATFORM	2	/* platform-specific (uname -i) */
1058 #define	DTRACE_CLASS_GROUP	3	/* hardware-group-specific (uname -m) */
1059 #define	DTRACE_CLASS_ISA	4	/* ISA-specific (uname -p) */
1060 #define	DTRACE_CLASS_COMMON	5	/* common to all systems */
1061 #define	DTRACE_CLASS_MAX	5	/* maximum valid class */
1062 
1063 #define	DTRACE_PRIV_NONE	0x0000
1064 #define	DTRACE_PRIV_KERNEL	0x0001
1065 #define	DTRACE_PRIV_USER	0x0002
1066 #define	DTRACE_PRIV_PROC	0x0004
1067 #define	DTRACE_PRIV_OWNER	0x0008
1068 
1069 #define	DTRACE_PRIV_ALL	\
1070 	(DTRACE_PRIV_KERNEL | DTRACE_PRIV_USER | \
1071 	DTRACE_PRIV_PROC | DTRACE_PRIV_OWNER)
1072 
1073 typedef struct dtrace_ppriv {
1074 	uint32_t dtpp_flags;			/* privilege flags */
1075 	uid_t dtpp_uid;				/* user ID */
1076 } dtrace_ppriv_t;
1077 
1078 typedef struct dtrace_attribute {
1079 	dtrace_stability_t dtat_name;		/* entity name stability */
1080 	dtrace_stability_t dtat_data;		/* entity data stability */
1081 	dtrace_class_t dtat_class;		/* entity data dependency */
1082 } dtrace_attribute_t;
1083 
1084 typedef struct dtrace_pattr {
1085 	dtrace_attribute_t dtpa_provider;	/* provider attributes */
1086 	dtrace_attribute_t dtpa_mod;		/* module attributes */
1087 	dtrace_attribute_t dtpa_func;		/* function attributes */
1088 	dtrace_attribute_t dtpa_name;		/* name attributes */
1089 	dtrace_attribute_t dtpa_args;		/* args[] attributes */
1090 } dtrace_pattr_t;
1091 
1092 typedef struct dtrace_providerdesc {
1093 	char dtvd_name[DTRACE_PROVNAMELEN];	/* provider name */
1094 	dtrace_pattr_t dtvd_attr;		/* stability attributes */
1095 	dtrace_ppriv_t dtvd_priv;		/* privileges required */
1096 } dtrace_providerdesc_t;
1097 
1098 /*
1099  * DTrace Pseudodevice Interface
1100  *
1101  * DTrace is controlled through ioctl(2)'s to the in-kernel dtrace:dtrace
1102  * pseudodevice driver.  These ioctls comprise the user-kernel interface to
1103  * DTrace.
1104  */
1105 #define	DTRACEIOC		(('d' << 24) | ('t' << 16) | ('r' << 8))
1106 #define	DTRACEIOC_PROVIDER	(DTRACEIOC | 1)		/* provider query */
1107 #define	DTRACEIOC_PROBES	(DTRACEIOC | 2)		/* probe query */
1108 #define	DTRACEIOC_BUFSNAP	(DTRACEIOC | 4)		/* snapshot buffer */
1109 #define	DTRACEIOC_PROBEMATCH	(DTRACEIOC | 5)		/* match probes */
1110 #define	DTRACEIOC_ENABLE	(DTRACEIOC | 6)		/* enable probes */
1111 #define	DTRACEIOC_AGGSNAP	(DTRACEIOC | 7)		/* snapshot agg. */
1112 #define	DTRACEIOC_EPROBE	(DTRACEIOC | 8)		/* get eprobe desc. */
1113 #define	DTRACEIOC_PROBEARG	(DTRACEIOC | 9)		/* get probe arg */
1114 #define	DTRACEIOC_CONF		(DTRACEIOC | 10)	/* get config. */
1115 #define	DTRACEIOC_STATUS	(DTRACEIOC | 11)	/* get status */
1116 #define	DTRACEIOC_GO		(DTRACEIOC | 12)	/* start tracing */
1117 #define	DTRACEIOC_STOP		(DTRACEIOC | 13)	/* stop tracing */
1118 #define	DTRACEIOC_AGGDESC	(DTRACEIOC | 15)	/* get agg. desc. */
1119 #define	DTRACEIOC_FORMAT	(DTRACEIOC | 16)	/* get format str */
1120 #define	DTRACEIOC_DOFGET	(DTRACEIOC | 17)	/* get DOF */
1121 #define	DTRACEIOC_REPLICATE	(DTRACEIOC | 18)	/* replicate enab */
1122 
1123 /*
1124  * DTrace Helpers
1125  *
1126  * In general, DTrace establishes probes in processes and takes actions on
1127  * processes without knowing their specific user-level structures.  Instead of
1128  * existing in the framework, process-specific knowledge is contained by the
1129  * enabling D program -- which can apply process-specific knowledge by making
1130  * appropriate use of DTrace primitives like copyin() and copyinstr() to
1131  * operate on user-level data.  However, there may exist some specific probes
1132  * of particular semantic relevance that the application developer may wish to
1133  * explicitly export.  For example, an application may wish to export a probe
1134  * at the point that it begins and ends certain well-defined transactions.  In
1135  * addition to providing probes, programs may wish to offer assistance for
1136  * certain actions.  For example, in highly dynamic environments (e.g., Java),
1137  * it may be difficult to obtain a stack trace in terms of meaningful symbol
1138  * names (the translation from instruction addresses to corresponding symbol
1139  * names may only be possible in situ); these environments may wish to define
1140  * a series of actions to be applied in situ to obtain a meaningful stack
1141  * trace.
1142  *
1143  * These two mechanisms -- user-level statically defined tracing and assisting
1144  * DTrace actions -- are provided via DTrace _helpers_.  Helpers are specified
1145  * via DOF, but unlike enabling DOF, helper DOF may contain definitions of
1146  * providers, probes and their arguments.  If a helper wishes to provide
1147  * action assistance, probe descriptions and corresponding DIF actions may be
1148  * specified in the helper DOF.  For such helper actions, however, the probe
1149  * description describes the specific helper:  all DTrace helpers have the
1150  * provider name "dtrace" and the module name "helper", and the name of the
1151  * helper is contained in the function name (for example, the ustack() helper
1152  * is named "ustack").  Any helper-specific name may be contained in the name
1153  * (for example, if a helper were to have a constructor, it might be named
1154  * "dtrace:helper:<helper>:init").  Helper actions are only called when the
1155  * action that they are helping is taken.  Helper actions may only return DIF
1156  * expressions, and may only call the following subroutines:
1157  *
1158  *    alloca()      <= Allocates memory out of the consumer's scratch space
1159  *    bcopy()       <= Copies memory to scratch space
1160  *    copyin()      <= Copies memory from user-level into consumer's scratch
1161  *    copyinto()    <= Copies memory into a specific location in scratch
1162  *    copyinstr()   <= Copies a string into a specific location in scratch
1163  *
1164  * Helper actions may only access the following built-in variables:
1165  *
1166  *    curthread     <= Current kthread_t pointer
1167  *    tid           <= Current thread identifier
1168  *    pid           <= Current process identifier
1169  *    execname      <= Current executable name
1170  *
1171  * Helper actions may not manipulate or allocate dynamic variables, but they
1172  * may have clause-local and statically-allocated global variables.  The
1173  * helper action variable state is specific to the helper action -- variables
1174  * used by the helper action may not be accessed outside of the helper
1175  * action, and the helper action may not access variables that like outside
1176  * of it.  Helper actions may not load from kernel memory at-large; they are
1177  * restricting to loading current user state (via copyin() and variants) and
1178  * scratch space.  As with probe enablings, helper actions are executed in
1179  * program order.  The result of the helper action is the result of the last
1180  * executing helper expression.
1181  *
1182  * Helpers -- composed of either providers/probes or probes/actions (or both)
1183  * -- are added by opening the "helper" minor node, and issuing an ioctl(2)
1184  * (DTRACEHIOC_ADDDOF) that specifies the dof_helper_t structure. This
1185  * encapsulates the name and base address of the user-level library or
1186  * executable publishing the helpers and probes as well as the DOF that
1187  * contains the definitions of those helpers and probes.
1188  *
1189  * The DTRACEHIOC_ADD and DTRACEHIOC_REMOVE are left in place for legacy
1190  * helpers and should no longer be used.  No other ioctls are valid on the
1191  * helper minor node.
1192  */
1193 #define	DTRACEHIOC		(('d' << 24) | ('t' << 16) | ('h' << 8))
1194 #define	DTRACEHIOC_ADD		(DTRACEHIOC | 1)	/* add helper */
1195 #define	DTRACEHIOC_REMOVE	(DTRACEHIOC | 2)	/* remove helper */
1196 #define	DTRACEHIOC_ADDDOF	(DTRACEHIOC | 3)	/* add helper DOF */
1197 
1198 typedef struct dof_helper {
1199 	char dofhp_mod[DTRACE_MODNAMELEN];	/* executable or library name */
1200 	uint64_t dofhp_addr;			/* base address of object */
1201 	uint64_t dofhp_dof;			/* address of helper DOF */
1202 } dof_helper_t;
1203 
1204 #define	DTRACEMNR_DTRACE	"dtrace"	/* node for DTrace ops */
1205 #define	DTRACEMNR_HELPER	"helper"	/* node for helpers */
1206 #define	DTRACEMNRN_DTRACE	0		/* minor for DTrace ops */
1207 #define	DTRACEMNRN_HELPER	1		/* minor for helpers */
1208 #define	DTRACEMNRN_CLONE	2		/* first clone minor */
1209 
1210 #ifdef _KERNEL
1211 
1212 /*
1213  * DTrace Provider API
1214  *
1215  * The following functions are implemented by the DTrace framework and are
1216  * used to implement separate in-kernel DTrace providers.  Common functions
1217  * are provided in uts/common/os/dtrace.c.  ISA-dependent subroutines are
1218  * defined in uts/<isa>/dtrace/dtrace_asm.s or uts/<isa>/dtrace/dtrace_isa.c.
1219  *
1220  * The provider API has two halves:  the API that the providers consume from
1221  * DTrace, and the API that providers make available to DTrace.
1222  *
1223  * 1 Framework-to-Provider API
1224  *
1225  * 1.1  Overview
1226  *
1227  * The Framework-to-Provider API is represented by the dtrace_pops structure
1228  * that the provider passes to the framework when registering itself.  This
1229  * structure consists of the following members:
1230  *
1231  *   dtps_provide()          <-- Provide all probes, all modules
1232  *   dtps_provide_module()   <-- Provide all probes in specified module
1233  *   dtps_enable()           <-- Enable specified probe
1234  *   dtps_disable()          <-- Disable specified probe
1235  *   dtps_suspend()          <-- Suspend specified probe
1236  *   dtps_resume()           <-- Resume specified probe
1237  *   dtps_getargdesc()       <-- Get the argument description for args[X]
1238  *   dtps_getargval()        <-- Get the value for an argX or args[X] variable
1239  *   dtps_usermode()         <-- Find out if the probe was fired in user mode
1240  *   dtps_destroy()          <-- Destroy all state associated with this probe
1241  *
1242  * 1.2  void dtps_provide(void *arg, const dtrace_probedesc_t *spec)
1243  *
1244  * 1.2.1  Overview
1245  *
1246  *   Called to indicate that the provider should provide all probes.  If the
1247  *   specified description is non-NULL, dtps_provide() is being called because
1248  *   no probe matched a specified probe -- if the provider has the ability to
1249  *   create custom probes, it may wish to create a probe that matches the
1250  *   specified description.
1251  *
1252  * 1.2.2  Arguments and notes
1253  *
1254  *   The first argument is the cookie as passed to dtrace_register().  The
1255  *   second argument is a pointer to a probe description that the provider may
1256  *   wish to consider when creating custom probes.  The provider is expected to
1257  *   call back into the DTrace framework via dtrace_probe_create() to create
1258  *   any necessary probes.  dtps_provide() may be called even if the provider
1259  *   has made available all probes; the provider should check the return value
1260  *   of dtrace_probe_create() to handle this case.  Note that the provider need
1261  *   not implement both dtps_provide() and dtps_provide_module(); see
1262  *   "Arguments and Notes" for dtrace_register(), below.
1263  *
1264  * 1.2.3  Return value
1265  *
1266  *   None.
1267  *
1268  * 1.2.4  Caller's context
1269  *
1270  *   dtps_provide() is typically called from open() or ioctl() context, but may
1271  *   be called from other contexts as well.  The DTrace framework is locked in
1272  *   such a way that providers may not register or unregister.  This means that
1273  *   the provider may not call any DTrace API that affects its registration with
1274  *   the framework, including dtrace_register(), dtrace_unregister(),
1275  *   dtrace_invalidate(), and dtrace_condense().  However, the context is such
1276  *   that the provider may (and indeed, is expected to) call probe-related
1277  *   DTrace routines, including dtrace_probe_create(), dtrace_probe_lookup(),
1278  *   and dtrace_probe_arg().
1279  *
1280  * 1.3  void dtps_provide_module(void *arg, struct modctl *mp)
1281  *
1282  * 1.3.1  Overview
1283  *
1284  *   Called to indicate that the provider should provide all probes in the
1285  *   specified module.
1286  *
1287  * 1.3.2  Arguments and notes
1288  *
1289  *   The first argument is the cookie as passed to dtrace_register().  The
1290  *   second argument is a pointer to a modctl structure that indicates the
1291  *   module for which probes should be created.
1292  *
1293  * 1.3.3  Return value
1294  *
1295  *   None.
1296  *
1297  * 1.3.4  Caller's context
1298  *
1299  *   dtps_provide_module() may be called from open() or ioctl() context, but
1300  *   may also be called from a module loading context.  mod_lock is held, and
1301  *   the DTrace framework is locked in such a way that providers may not
1302  *   register or unregister.  This means that the provider may not call any
1303  *   DTrace API that affects its registration with the framework, including
1304  *   dtrace_register(), dtrace_unregister(), dtrace_invalidate(), and
1305  *   dtrace_condense().  However, the context is such that the provider may (and
1306  *   indeed, is expected to) call probe-related DTrace routines, including
1307  *   dtrace_probe_create(), dtrace_probe_lookup(), and dtrace_probe_arg().  Note
1308  *   that the provider need not implement both dtps_provide() and
1309  *   dtps_provide_module(); see "Arguments and Notes" for dtrace_register(),
1310  *   below.
1311  *
1312  * 1.4  void dtps_enable(void *arg, dtrace_id_t id, void *parg)
1313  *
1314  * 1.4.1  Overview
1315  *
1316  *   Called to enable the specified probe.
1317  *
1318  * 1.4.2  Arguments and notes
1319  *
1320  *   The first argument is the cookie as passed to dtrace_register().  The
1321  *   second argument is the identifier of the probe to be enabled.  The third
1322  *   argument is the probe argument as passed to dtrace_probe_create().
1323  *   dtps_enable() will be called when a probe transitions from not being
1324  *   enabled at all to having one or more ECB.  The number of ECBs associated
1325  *   with the probe may change without subsequent calls into the provider.
1326  *   When the number of ECBs drops to zero, the provider will be explicitly
1327  *   told to disable the probe via dtps_disable().  dtrace_probe() should never
1328  *   be called for a probe identifier that hasn't been explicitly enabled via
1329  *   dtps_enable().
1330  *
1331  * 1.4.3  Return value
1332  *
1333  *   None.
1334  *
1335  * 1.4.4  Caller's context
1336  *
1337  *   The DTrace framework is locked in such a way that it may not be called
1338  *   back into at all.  cpu_lock is held.  mod_lock is not held and may not
1339  *   be acquired.
1340  *
1341  * 1.5  void dtps_disable(void *arg, dtrace_id_t id, void *parg)
1342  *
1343  * 1.5.1  Overview
1344  *
1345  *   Called to disable the specified probe.
1346  *
1347  * 1.5.2  Arguments and notes
1348  *
1349  *   The first argument is the cookie as passed to dtrace_register().  The
1350  *   second argument is the identifier of the probe to be disabled.  The third
1351  *   argument is the probe argument as passed to dtrace_probe_create().
1352  *   dtps_disable() will be called when a probe transitions from being enabled
1353  *   to having zero ECBs.  dtrace_probe() should never be called for a probe
1354  *   identifier that has been explicitly enabled via dtps_disable().
1355  *
1356  * 1.5.3  Return value
1357  *
1358  *   None.
1359  *
1360  * 1.5.4  Caller's context
1361  *
1362  *   The DTrace framework is locked in such a way that it may not be called
1363  *   back into at all.  cpu_lock is held.  mod_lock is not held and may not
1364  *   be acquired.
1365  *
1366  * 1.6  void dtps_suspend(void *arg, dtrace_id_t id, void *parg)
1367  *
1368  * 1.6.1  Overview
1369  *
1370  *   Called to suspend the specified enabled probe.  This entry point is for
1371  *   providers that may need to suspend some or all of their probes when CPUs
1372  *   are being powered on or when the boot monitor is being entered for a
1373  *   prolonged period of time.
1374  *
1375  * 1.6.2  Arguments and notes
1376  *
1377  *   The first argument is the cookie as passed to dtrace_register().  The
1378  *   second argument is the identifier of the probe to be suspended.  The
1379  *   third argument is the probe argument as passed to dtrace_probe_create().
1380  *   dtps_suspend will only be called on an enabled probe.  Providers that
1381  *   provide a dtps_suspend entry point will want to take roughly the action
1382  *   that it takes for dtps_disable.
1383  *
1384  * 1.6.3  Return value
1385  *
1386  *   None.
1387  *
1388  * 1.6.4  Caller's context
1389  *
1390  *   Interrupts are disabled.  The DTrace framework is in a state such that the
1391  *   specified probe cannot be disabled or destroyed for the duration of
1392  *   dtps_suspend().  As interrupts are disabled, the provider is afforded
1393  *   little latitude; the provider is expected to do no more than a store to
1394  *   memory.
1395  *
1396  * 1.7  void dtps_resume(void *arg, dtrace_id_t id, void *parg)
1397  *
1398  * 1.7.1  Overview
1399  *
1400  *   Called to resume the specified enabled probe.  This entry point is for
1401  *   providers that may need to resume some or all of their probes after the
1402  *   completion of an event that induced a call to dtps_suspend().
1403  *
1404  * 1.7.2  Arguments and notes
1405  *
1406  *   The first argument is the cookie as passed to dtrace_register().  The
1407  *   second argument is the identifier of the probe to be resumed.  The
1408  *   third argument is the probe argument as passed to dtrace_probe_create().
1409  *   dtps_resume will only be called on an enabled probe.  Providers that
1410  *   provide a dtps_resume entry point will want to take roughly the action
1411  *   that it takes for dtps_enable.
1412  *
1413  * 1.7.3  Return value
1414  *
1415  *   None.
1416  *
1417  * 1.7.4  Caller's context
1418  *
1419  *   Interrupts are disabled.  The DTrace framework is in a state such that the
1420  *   specified probe cannot be disabled or destroyed for the duration of
1421  *   dtps_resume().  As interrupts are disabled, the provider is afforded
1422  *   little latitude; the provider is expected to do no more than a store to
1423  *   memory.
1424  *
1425  * 1.8  void dtps_getargdesc(void *arg, dtrace_id_t id, void *parg,
1426  *           dtrace_argdesc_t *desc)
1427  *
1428  * 1.8.1  Overview
1429  *
1430  *   Called to retrieve the argument description for an args[X] variable.
1431  *
1432  * 1.8.2  Arguments and notes
1433  *
1434  *   The first argument is the cookie as passed to dtrace_register(). The
1435  *   second argument is the identifier of the current probe. The third
1436  *   argument is the probe argument as passed to dtrace_probe_create(). The
1437  *   fourth argument is a pointer to the argument description.  This
1438  *   description is both an input and output parameter:  it contains the
1439  *   index of the desired argument in the dtargd_ndx field, and expects
1440  *   the other fields to be filled in upon return.  If there is no argument
1441  *   corresponding to the specified index, the dtargd_ndx field should be set
1442  *   to DTRACE_ARGNONE.
1443  *
1444  * 1.8.3  Return value
1445  *
1446  *   None.  The dtargd_ndx, dtargd_native, dtargd_xlate and dtargd_mapping
1447  *   members of the dtrace_argdesc_t structure are all output values.
1448  *
1449  * 1.8.4  Caller's context
1450  *
1451  *   dtps_getargdesc() is called from ioctl() context. mod_lock is held, and
1452  *   the DTrace framework is locked in such a way that providers may not
1453  *   register or unregister.  This means that the provider may not call any
1454  *   DTrace API that affects its registration with the framework, including
1455  *   dtrace_register(), dtrace_unregister(), dtrace_invalidate(), and
1456  *   dtrace_condense().
1457  *
1458  * 1.9  uint64_t dtps_getargval(void *arg, dtrace_id_t id, void *parg,
1459  *               int argno, int aframes)
1460  *
1461  * 1.9.1  Overview
1462  *
1463  *   Called to retrieve a value for an argX or args[X] variable.
1464  *
1465  * 1.9.2  Arguments and notes
1466  *
1467  *   The first argument is the cookie as passed to dtrace_register(). The
1468  *   second argument is the identifier of the current probe. The third
1469  *   argument is the probe argument as passed to dtrace_probe_create(). The
1470  *   fourth argument is the number of the argument (the X in the example in
1471  *   1.9.1). The fifth argument is the number of stack frames that were used
1472  *   to get from the actual place in the code that fired the probe to
1473  *   dtrace_probe() itself, the so-called artificial frames. This argument may
1474  *   be used to descend an appropriate number of frames to find the correct
1475  *   values. If this entry point is left NULL, the dtrace_getarg() built-in
1476  *   function is used.
1477  *
1478  * 1.9.3  Return value
1479  *
1480  *   The value of the argument.
1481  *
1482  * 1.9.4  Caller's context
1483  *
1484  *   This is called from within dtrace_probe() meaning that interrupts
1485  *   are disabled. No locks should be taken within this entry point.
1486  *
1487  * 1.10  int dtps_usermode(void *arg, dtrace_id_t id, void *parg)
1488  *
1489  * 1.10.1  Overview
1490  *
1491  *   Called to determine if the probe was fired in a user context.
1492  *
1493  * 1.10.2  Arguments and notes
1494  *
1495  *   The first argument is the cookie as passed to dtrace_register(). The
1496  *   second argument is the identifier of the current probe. The third
1497  *   argument is the probe argument as passed to dtrace_probe_create().  This
1498  *   entry point must not be left NULL for providers whose probes allow for
1499  *   mixed mode tracing, that is to say those probes that can fire during
1500  *   kernel- _or_ user-mode execution
1501  *
1502  * 1.10.3  Return value
1503  *
1504  *   A boolean value.
1505  *
1506  * 1.10.4  Caller's context
1507  *
1508  *   This is called from within dtrace_probe() meaning that interrupts
1509  *   are disabled. No locks should be taken within this entry point.
1510  *
1511  * 1.11 void dtps_destroy(void *arg, dtrace_id_t id, void *parg)
1512  *
1513  * 1.11.1 Overview
1514  *
1515  *   Called to destroy the specified probe.
1516  *
1517  * 1.11.2 Arguments and notes
1518  *
1519  *   The first argument is the cookie as passed to dtrace_register().  The
1520  *   second argument is the identifier of the probe to be destroyed.  The third
1521  *   argument is the probe argument as passed to dtrace_probe_create().  The
1522  *   provider should free all state associated with the probe.  The framework
1523  *   guarantees that dtps_destroy() is only called for probes that have either
1524  *   been disabled via dtps_disable() or were never enabled via dtps_enable().
1525  *   Once dtps_disable() has been called for a probe, no further call will be
1526  *   made specifying the probe.
1527  *
1528  * 1.11.3 Return value
1529  *
1530  *   None.
1531  *
1532  * 1.11.4 Caller's context
1533  *
1534  *   The DTrace framework is locked in such a way that it may not be called
1535  *   back into at all.  mod_lock is held.  cpu_lock is not held, and may not be
1536  *   acquired.
1537  *
1538  *
1539  * 2 Provider-to-Framework API
1540  *
1541  * 2.1  Overview
1542  *
1543  * The Provider-to-Framework API provides the mechanism for the provider to
1544  * register itself with the DTrace framework, to create probes, to lookup
1545  * probes and (most importantly) to fire probes.  The Provider-to-Framework
1546  * consists of:
1547  *
1548  *   dtrace_register()       <-- Register a provider with the DTrace framework
1549  *   dtrace_unregister()     <-- Remove a provider's DTrace registration
1550  *   dtrace_invalidate()     <-- Invalidate the specified provider
1551  *   dtrace_condense()       <-- Remove a provider's unenabled probes
1552  *   dtrace_attached()       <-- Indicates whether or not DTrace has attached
1553  *   dtrace_probe_create()   <-- Create a DTrace probe
1554  *   dtrace_probe_lookup()   <-- Lookup a DTrace probe based on its name
1555  *   dtrace_probe_arg()      <-- Return the probe argument for a specific probe
1556  *   dtrace_probe()          <-- Fire the specified probe
1557  *
1558  * 2.2  int dtrace_register(const char *name, const dtrace_pattr_t *pap,
1559  *          uint32_t priv, uid_t uid, const dtrace_pops_t *pops, void *arg,
1560  *          dtrace_provider_id_t *idp)
1561  *
1562  * 2.2.1  Overview
1563  *
1564  *   dtrace_register() registers the calling provider with the DTrace
1565  *   framework.  It should generally be called by DTrace providers in their
1566  *   attach(9E) entry point.
1567  *
1568  * 2.2.2  Arguments and Notes
1569  *
1570  *   The first argument is the name of the provider.  The second argument is a
1571  *   pointer to the stability attributes for the provider.  The third argument
1572  *   is the privilege flags for the provider, and must be some combination of:
1573  *
1574  *     DTRACE_PRIV_NONE     <= All users may enable probes from this provider
1575  *
1576  *     DTRACE_PRIV_PROC     <= Any user with privilege of PRIV_DTRACE_PROC may
1577  *                             enable probes from this provider
1578  *
1579  *     DTRACE_PRIV_USER     <= Any user with privilege of PRIV_DTRACE_USER may
1580  *                             enable probes from this provider
1581  *
1582  *     DTRACE_PRIV_KERNEL   <= Any user with privilege of PRIV_DTRACE_KERNEL
1583  *                             may enable probes from this provider
1584  *
1585  *     DTRACE_PRIV_OWNER    <= This flag places an additional constraint on
1586  *                             the privilege requirements above. These probes
1587  *                             require either (a) a user ID matching the user
1588  *                             ID passed as the fourth argument to
1589  *                             dtrace_register() or (b) the PRIV_PROC_OWNER
1590  *                             privilege.
1591  *
1592  *   Note that these flags designate the _visibility_ of the probes, not
1593  *   the conditions under which they may or may not fire.
1594  *
1595  *   The fourth argument is a user ID that is associated with the provider.
1596  *   This argument should be 0 if the privilege flags don't include
1597  *   DTRACE_PRIV_OWNER.
1598  *
1599  *   The fifth argument is a DTrace provider operations vector, which provides
1600  *   the implementation for the Framework-to-Provider API.  (See Section 1,
1601  *   above.)  This must be non-NULL, and each member must be non-NULL.  The
1602  *   exceptions to this are (1) the dtps_provide() and dtps_provide_module()
1603  *   members (if the provider so desires, _one_ of these members may be left
1604  *   NULL -- denoting that the provider only implements the other) and (2)
1605  *   the dtps_suspend() and dtps_resume() members, which must either both be
1606  *   NULL or both be non-NULL.
1607  *
1608  *   The sixth argument is a cookie to be specified as the first argument for
1609  *   each function in the Framework-to-Provider API.  This argument may have
1610  *   any value.
1611  *
1612  *   The final argument is a pointer to dtrace_provider_id_t.  If
1613  *   dtrace_register() successfully completes, the provider identifier will be
1614  *   stored in the memory pointed to be this argument.  This argument must be
1615  *   non-NULL.
1616  *
1617  * 2.2.3  Return value
1618  *
1619  *   On success, dtrace_register() returns 0 and stores the new provider's
1620  *   identifier into the memory pointed to by the idp argument.  On failure,
1621  *   dtrace_register() returns an errno:
1622  *
1623  *     EINVAL   The arguments passed to dtrace_register() were somehow invalid.
1624  *              This may because a parameter that must be non-NULL was NULL,
1625  *              because the name was invalid (either empty or an illegal
1626  *              provider name) or because the attributes were invalid.
1627  *
1628  *   No other failure code is returned.
1629  *
1630  * 2.2.4  Caller's context
1631  *
1632  *   dtrace_register() may induce calls to dtrace_provide(); the provider must
1633  *   hold no locks across dtrace_register() that may also be acquired by
1634  *   dtrace_provide().  cpu_lock and mod_lock must not be held.
1635  *
1636  * 2.3  int dtrace_unregister(dtrace_provider_t id)
1637  *
1638  * 2.3.1  Overview
1639  *
1640  *   Unregisters the specified provider from the DTrace framework.  It should
1641  *   generally be called by DTrace providers in their detach(9E) entry point.
1642  *
1643  * 2.3.2  Arguments and Notes
1644  *
1645  *   The only argument is the provider identifier, as returned from a
1646  *   successful call to dtrace_register().  As a result of calling
1647  *   dtrace_unregister(), the DTrace framework will call back into the provider
1648  *   via the dtps_destroy() entry point.  Once dtrace_unregister() successfully
1649  *   completes, however, the DTrace framework will no longer make calls through
1650  *   the Framework-to-Provider API.
1651  *
1652  * 2.3.3  Return value
1653  *
1654  *   On success, dtrace_unregister returns 0.  On failure, dtrace_unregister()
1655  *   returns an errno:
1656  *
1657  *     EBUSY    There are currently processes that have the DTrace pseudodevice
1658  *              open, or there exists an anonymous enabling that hasn't yet
1659  *              been claimed.
1660  *
1661  *   No other failure code is returned.
1662  *
1663  * 2.3.4  Caller's context
1664  *
1665  *   Because a call to dtrace_unregister() may induce calls through the
1666  *   Framework-to-Provider API, the caller may not hold any lock across
1667  *   dtrace_register() that is also acquired in any of the Framework-to-
1668  *   Provider API functions.  Additionally, mod_lock may not be held.
1669  *
1670  * 2.4  void dtrace_invalidate(dtrace_provider_id_t id)
1671  *
1672  * 2.4.1  Overview
1673  *
1674  *   Invalidates the specified provider.  All subsequent probe lookups for the
1675  *   specified provider will fail, but its probes will not be removed.
1676  *
1677  * 2.4.2  Arguments and note
1678  *
1679  *   The only argument is the provider identifier, as returned from a
1680  *   successful call to dtrace_register().  In general, a provider's probes
1681  *   always remain valid; dtrace_invalidate() is a mechanism for invalidating
1682  *   an entire provider, regardless of whether or not probes are enabled or
1683  *   not.  Note that dtrace_invalidate() will _not_ prevent already enabled
1684  *   probes from firing -- it will merely prevent any new enablings of the
1685  *   provider's probes.
1686  *
1687  * 2.5 int dtrace_condense(dtrace_provider_id_t id)
1688  *
1689  * 2.5.1  Overview
1690  *
1691  *   Removes all the unenabled probes for the given provider. This function is
1692  *   not unlike dtrace_unregister(), except that it doesn't remove the
1693  *   provider just as many of its associated probes as it can.
1694  *
1695  * 2.5.2  Arguments and Notes
1696  *
1697  *   As with dtrace_unregister(), the sole argument is the provider identifier
1698  *   as returned from a successful call to dtrace_register().  As a result of
1699  *   calling dtrace_condense(), the DTrace framework will call back into the
1700  *   given provider's dtps_destroy() entry point for each of the provider's
1701  *   unenabled probes.
1702  *
1703  * 2.5.3  Return value
1704  *
1705  *   Currently, dtrace_condense() always returns 0.  However, consumers of this
1706  *   function should check the return value as appropriate; its behavior may
1707  *   change in the future.
1708  *
1709  * 2.5.4  Caller's context
1710  *
1711  *   As with dtrace_unregister(), the caller may not hold any lock across
1712  *   dtrace_condense() that is also acquired in the provider's entry points.
1713  *   Also, mod_lock may not be held.
1714  *
1715  * 2.6 int dtrace_attached()
1716  *
1717  * 2.6.1  Overview
1718  *
1719  *   Indicates whether or not DTrace has attached.
1720  *
1721  * 2.6.2  Arguments and Notes
1722  *
1723  *   For most providers, DTrace makes initial contact beyond registration.
1724  *   That is, once a provider has registered with DTrace, it waits to hear
1725  *   from DTrace to create probes.  However, some providers may wish to
1726  *   proactively create probes without first being told by DTrace to do so.
1727  *   If providers wish to do this, they must first call dtrace_attached() to
1728  *   determine if DTrace itself has attached.  If dtrace_attached() returns 0,
1729  *   the provider must not make any other Provider-to-Framework API call.
1730  *
1731  * 2.6.3  Return value
1732  *
1733  *   dtrace_attached() returns 1 if DTrace has attached, 0 otherwise.
1734  *
1735  * 2.7  int dtrace_probe_create(dtrace_provider_t id, const char *mod,
1736  *	    const char *func, const char *name, int aframes, void *arg)
1737  *
1738  * 2.7.1  Overview
1739  *
1740  *   Creates a probe with specified module name, function name, and name.
1741  *
1742  * 2.7.2  Arguments and Notes
1743  *
1744  *   The first argument is the provider identifier, as returned from a
1745  *   successful call to dtrace_register().  The second, third, and fourth
1746  *   arguments are the module name, function name, and probe name,
1747  *   respectively.  Of these, module name and function name may both be NULL
1748  *   (in which case the probe is considered to be unanchored), or they may both
1749  *   be non-NULL.  The name must be non-NULL, and must point to a non-empty
1750  *   string.
1751  *
1752  *   The fifth argument is the number of artificial stack frames that will be
1753  *   found on the stack when dtrace_probe() is called for the new probe.  These
1754  *   artificial frames will be automatically be pruned should the stack() or
1755  *   stackdepth() functions be called as part of one of the probe's ECBs.  If
1756  *   the parameter doesn't add an artificial frame, this parameter should be
1757  *   zero.
1758  *
1759  *   The final argument is a probe argument that will be passed back to the
1760  *   provider when a probe-specific operation is called.  (e.g., via
1761  *   dtps_enable(), dtps_disable(), etc.)
1762  *
1763  *   Note that it is up to the provider to be sure that the probe that it
1764  *   creates does not already exist -- if the provider is unsure of the probe's
1765  *   existence, it should assure its absence with dtrace_probe_lookup() before
1766  *   calling dtrace_probe_create().
1767  *
1768  * 2.7.3  Return value
1769  *
1770  *   dtrace_probe_create() always succeeds, and always returns the identifier
1771  *   of the newly-created probe.
1772  *
1773  * 2.7.4  Caller's context
1774  *
1775  *   While dtrace_probe_create() is generally expected to be called from
1776  *   dtps_provide() and/or dtps_provide_module(), it may be called from other
1777  *   non-DTrace contexts.  Neither cpu_lock nor mod_lock may be held.
1778  *
1779  * 2.8  dtrace_id_t dtrace_probe_lookup(dtrace_provider_t id, const char *mod,
1780  *	    const char *func, const char *name)
1781  *
1782  * 2.8.1  Overview
1783  *
1784  *   Looks up a probe based on provdider and one or more of module name,
1785  *   function name and probe name.
1786  *
1787  * 2.8.2  Arguments and Notes
1788  *
1789  *   The first argument is the provider identifier, as returned from a
1790  *   successful call to dtrace_register().  The second, third, and fourth
1791  *   arguments are the module name, function name, and probe name,
1792  *   respectively.  Any of these may be NULL; dtrace_probe_lookup() will return
1793  *   the identifier of the first probe that is provided by the specified
1794  *   provider and matches all of the non-NULL matching criteria.
1795  *   dtrace_probe_lookup() is generally used by a provider to be check the
1796  *   existence of a probe before creating it with dtrace_probe_create().
1797  *
1798  * 2.8.3  Return value
1799  *
1800  *   If the probe exists, returns its identifier.  If the probe does not exist,
1801  *   return DTRACE_IDNONE.
1802  *
1803  * 2.8.4  Caller's context
1804  *
1805  *   While dtrace_probe_lookup() is generally expected to be called from
1806  *   dtps_provide() and/or dtps_provide_module(), it may also be called from
1807  *   other non-DTrace contexts.  Neither cpu_lock nor mod_lock may be held.
1808  *
1809  * 2.9  void *dtrace_probe_arg(dtrace_provider_t id, dtrace_id_t probe)
1810  *
1811  * 2.9.1  Overview
1812  *
1813  *   Returns the probe argument associated with the specified probe.
1814  *
1815  * 2.9.2  Arguments and Notes
1816  *
1817  *   The first argument is the provider identifier, as returned from a
1818  *   successful call to dtrace_register().  The second argument is a probe
1819  *   identifier, as returned from dtrace_probe_lookup() or
1820  *   dtrace_probe_create().  This is useful if a probe has multiple
1821  *   provider-specific components to it:  the provider can create the probe
1822  *   once with provider-specific state, and then add to the state by looking
1823  *   up the probe based on probe identifier.
1824  *
1825  * 2.9.3  Return value
1826  *
1827  *   Returns the argument associated with the specified probe.  If the
1828  *   specified probe does not exist, or if the specified probe is not provided
1829  *   by the specified provider, NULL is returned.
1830  *
1831  * 2.9.4  Caller's context
1832  *
1833  *   While dtrace_probe_arg() is generally expected to be called from
1834  *   dtps_provide() and/or dtps_provide_module(), it may also be called from
1835  *   other non-DTrace contexts.  Neither cpu_lock nor mod_lock may be held.
1836  *
1837  * 2.10  void dtrace_probe(dtrace_id_t probe, uintptr_t arg0, uintptr_t arg1,
1838  *		uintptr_t arg2, uintptr_t arg3, uintptr_t arg4)
1839  *
1840  * 2.10.1  Overview
1841  *
1842  *   The epicenter of DTrace:  fires the specified probes with the specified
1843  *   arguments.
1844  *
1845  * 2.10.2  Arguments and Notes
1846  *
1847  *   The first argument is a probe identifier as returned by
1848  *   dtrace_probe_create() or dtrace_probe_lookup().  The second through sixth
1849  *   arguments are the values to which the D variables "arg0" through "arg4"
1850  *   will be mapped.
1851  *
1852  *   dtrace_probe() should be called whenever the specified probe has fired --
1853  *   however the provider defines it.
1854  *
1855  * 2.10.3  Return value
1856  *
1857  *   None.
1858  *
1859  * 2.10.4  Caller's context
1860  *
1861  *   dtrace_probe() may be called in virtually any context:  kernel, user,
1862  *   interrupt, high-level interrupt, with arbitrary adaptive locks held, with
1863  *   dispatcher locks held, with interrupts disabled, etc.  The only latitude
1864  *   that must be afforded to DTrace is the ability to make calls within
1865  *   itself (and to its in-kernel subroutines) and the ability to access
1866  *   arbitrary (but mapped) memory.  On some platforms, this constrains
1867  *   context.  For example, on UltraSPARC, dtrace_probe() cannot be called
1868  *   from any context in which TL is greater than zero.  dtrace_probe() may
1869  *   also not be called from any routine which may be called by dtrace_probe()
1870  *   -- which includes functions in the DTrace framework and some in-kernel
1871  *   DTrace subroutines.  All such functions "dtrace_"; providers that
1872  *   instrument the kernel arbitrarily should be sure to not instrument these
1873  *   routines.
1874  */
1875 typedef struct dtrace_pops {
1876 	void (*dtps_provide)(void *arg, const dtrace_probedesc_t *spec);
1877 	void (*dtps_provide_module)(void *arg, struct modctl *mp);
1878 	void (*dtps_enable)(void *arg, dtrace_id_t id, void *parg);
1879 	void (*dtps_disable)(void *arg, dtrace_id_t id, void *parg);
1880 	void (*dtps_suspend)(void *arg, dtrace_id_t id, void *parg);
1881 	void (*dtps_resume)(void *arg, dtrace_id_t id, void *parg);
1882 	void (*dtps_getargdesc)(void *arg, dtrace_id_t id, void *parg,
1883 	    dtrace_argdesc_t *desc);
1884 	uint64_t (*dtps_getargval)(void *arg, dtrace_id_t id, void *parg,
1885 	    int argno, int aframes);
1886 	int (*dtps_usermode)(void *arg, dtrace_id_t id, void *parg);
1887 	void (*dtps_destroy)(void *arg, dtrace_id_t id, void *parg);
1888 } dtrace_pops_t;
1889 
1890 typedef uintptr_t	dtrace_provider_id_t;
1891 
1892 extern int dtrace_register(const char *, const dtrace_pattr_t *, uint32_t,
1893     uid_t, const dtrace_pops_t *, void *, dtrace_provider_id_t *);
1894 extern int dtrace_unregister(dtrace_provider_id_t);
1895 extern int dtrace_condense(dtrace_provider_id_t);
1896 extern void dtrace_invalidate(dtrace_provider_id_t);
1897 extern dtrace_id_t dtrace_probe_lookup(dtrace_provider_id_t, const char *,
1898     const char *, const char *);
1899 extern dtrace_id_t dtrace_probe_create(dtrace_provider_id_t, const char *,
1900     const char *, const char *, int, void *);
1901 extern void *dtrace_probe_arg(dtrace_provider_id_t, dtrace_id_t);
1902 extern void dtrace_probe(dtrace_id_t, uintptr_t arg0, uintptr_t arg1,
1903     uintptr_t arg2, uintptr_t arg3, uintptr_t arg4);
1904 
1905 /*
1906  * DTrace Meta Provider API
1907  *
1908  * The following functions are implemented by the DTrace framework and are
1909  * used to implement meta providers. Meta providers plug into the DTrace
1910  * framework and are used to instantiate new providers on the fly. At
1911  * present, there is only one type of meta provider and only one meta
1912  * provider may be registered with the DTrace framework at a time. The
1913  * sole meta provider type provides user-land static tracing facilities
1914  * by taking meta probe descriptions and adding a corresponding provider
1915  * into the DTrace framework.
1916  *
1917  * 1 Framework-to-Provider
1918  *
1919  * 1.1 Overview
1920  *
1921  * The Framework-to-Provider API is represented by the dtrace_mops structure
1922  * that the meta provider passes to the framework when registering itself as
1923  * a meta provider. This structure consists of the following members:
1924  *
1925  *   dtms_create_probe()	<-- Add a new probe to a created provider
1926  *   dtms_provide_pid()		<-- Create a new provider for a given process
1927  *   dtms_remove_pid()		<-- Remove a previously created provider
1928  *
1929  * 1.2  void dtms_create_probe(void *arg, void *parg,
1930  *           dtrace_helper_probedesc_t *probedesc);
1931  *
1932  * 1.2.1  Overview
1933  *
1934  *   Called by the DTrace framework to create a new probe in a provider
1935  *   created by this meta provider.
1936  *
1937  * 1.2.2  Arguments and notes
1938  *
1939  *   The first argument is the cookie as passed to dtrace_meta_register().
1940  *   The second argument is the provider cookie for the associated provider;
1941  *   this is obtained from the return value of dtms_provide_pid(). The third
1942  *   argument is the helper probe description.
1943  *
1944  * 1.2.3  Return value
1945  *
1946  *   None
1947  *
1948  * 1.2.4  Caller's context
1949  *
1950  *   dtms_create_probe() is called from either ioctl() or module load context.
1951  *   The DTrace framework is locked in such a way that meta providers may not
1952  *   register or unregister. This means that the meta provider cannot call
1953  *   dtrace_meta_register() or dtrace_meta_unregister(). However, the context is
1954  *   such that the provider may (and is expected to) call provider-related
1955  *   DTrace provider APIs including dtrace_probe_create().
1956  *
1957  * 1.3  void *dtms_provide_pid(void *arg, dtrace_meta_provider_t *mprov,
1958  *	      pid_t pid)
1959  *
1960  * 1.3.1  Overview
1961  *
1962  *   Called by the DTrace framework to instantiate a new provider given the
1963  *   description of the provider and probes in the mprov argument. The
1964  *   meta provider should call dtrace_register() to insert the new provider
1965  *   into the DTrace framework.
1966  *
1967  * 1.3.2  Arguments and notes
1968  *
1969  *   The first argument is the cookie as passed to dtrace_meta_register().
1970  *   The second argument is a pointer to a structure describing the new
1971  *   helper provider. The third argument is the process identifier for
1972  *   process associated with this new provider. Note that the name of the
1973  *   provider as passed to dtrace_register() should be the contatenation of
1974  *   the dtmpb_provname member of the mprov argument and the processs
1975  *   identifier as a string.
1976  *
1977  * 1.3.3  Return value
1978  *
1979  *   The cookie for the provider that the meta provider creates. This is
1980  *   the same value that it passed to dtrace_register().
1981  *
1982  * 1.3.4  Caller's context
1983  *
1984  *   dtms_provide_pid() is called from either ioctl() or module load context.
1985  *   The DTrace framework is locked in such a way that meta providers may not
1986  *   register or unregister. This means that the meta provider cannot call
1987  *   dtrace_meta_register() or dtrace_meta_unregister(). However, the context
1988  *   is such that the provider may -- and is expected to --  call
1989  *   provider-related DTrace provider APIs including dtrace_register().
1990  *
1991  * 1.4  void dtms_remove_pid(void *arg, dtrace_meta_provider_t *mprov,
1992  *	     pid_t pid)
1993  *
1994  * 1.4.1  Overview
1995  *
1996  *   Called by the DTrace framework to remove a provider that had previously
1997  *   been instantiated via the dtms_provide_pid() entry point. The meta
1998  *   provider need not remove the provider immediately, but this entry
1999  *   point indicates that the provider should be removed as soon as possible
2000  *   using the dtrace_unregister() API.
2001  *
2002  * 1.4.2  Arguments and notes
2003  *
2004  *   The first argument is the cookie as passed to dtrace_meta_register().
2005  *   The second argument is a pointer to a structure describing the helper
2006  *   provider. The third argument is the process identifier for process
2007  *   associated with this new provider.
2008  *
2009  * 1.4.3  Return value
2010  *
2011  *   None
2012  *
2013  * 1.4.4  Caller's context
2014  *
2015  *   dtms_remove_pid() is called from either ioctl() or exit() context.
2016  *   The DTrace framework is locked in such a way that meta providers may not
2017  *   register or unregister. This means that the meta provider cannot call
2018  *   dtrace_meta_register() or dtrace_meta_unregister(). However, the context
2019  *   is such that the provider may -- and is expected to -- call
2020  *   provider-related DTrace provider APIs including dtrace_unregister().
2021  */
2022 typedef struct dtrace_helper_probedesc {
2023 	char *dthpb_mod;			/* probe module */
2024 	char *dthpb_func; 			/* probe function */
2025 	char *dthpb_name; 			/* probe name */
2026 	uint64_t dthpb_base;			/* base address */
2027 	uint32_t *dthpb_offs;			/* offsets array */
2028 	uint32_t dthpb_noffs;			/* offsets count */
2029 	uint8_t *dthpb_args;			/* argument mapping array */
2030 	uint8_t dthpb_xargc;			/* translated argument count */
2031 	uint8_t dthpb_nargc;			/* native argument count */
2032 	char *dthpb_xtypes;			/* translated types strings */
2033 	char *dthpb_ntypes;			/* native types strings */
2034 } dtrace_helper_probedesc_t;
2035 
2036 typedef struct dtrace_helper_provdesc {
2037 	char *dthpv_provname;			/* provider name */
2038 	dtrace_pattr_t dthpv_pattr;		/* stability attributes */
2039 } dtrace_helper_provdesc_t;
2040 
2041 typedef struct dtrace_mops {
2042 	void (*dtms_create_probe)(void *, void *, dtrace_helper_probedesc_t *);
2043 	void *(*dtms_provide_pid)(void *, dtrace_helper_provdesc_t *, pid_t);
2044 	void (*dtms_remove_pid)(void *, dtrace_helper_provdesc_t *, pid_t);
2045 } dtrace_mops_t;
2046 
2047 typedef uintptr_t	dtrace_meta_provider_id_t;
2048 
2049 extern int dtrace_meta_register(const char *, const dtrace_mops_t *, void *,
2050     dtrace_meta_provider_id_t *);
2051 extern int dtrace_meta_unregister(dtrace_meta_provider_id_t);
2052 
2053 /*
2054  * DTrace Kernel Hooks
2055  *
2056  * The following functions are implemented by the base kernel and form a set of
2057  * hooks used by the DTrace framework.  DTrace hooks are implemented in either
2058  * uts/common/os/dtrace_subr.c, an ISA-specific assembly file, or in a
2059  * uts/<platform>/os/dtrace_subr.c corresponding to each hardware platform.
2060  */
2061 
2062 typedef enum dtrace_vtime_state {
2063 	DTRACE_VTIME_INACTIVE = 0,	/* No DTrace, no TNF */
2064 	DTRACE_VTIME_ACTIVE,		/* DTrace virtual time, no TNF */
2065 	DTRACE_VTIME_INACTIVE_TNF,	/* No DTrace, TNF active */
2066 	DTRACE_VTIME_ACTIVE_TNF		/* DTrace virtual time _and_ TNF */
2067 } dtrace_vtime_state_t;
2068 
2069 extern dtrace_vtime_state_t dtrace_vtime_active;
2070 extern void dtrace_vtime_switch(kthread_t *next);
2071 extern void dtrace_vtime_enable_tnf(void);
2072 extern void dtrace_vtime_disable_tnf(void);
2073 extern void dtrace_vtime_enable(void);
2074 extern void dtrace_vtime_disable(void);
2075 
2076 struct regs;
2077 
2078 extern int (*dtrace_pid_probe_ptr)(struct regs *);
2079 extern int (*dtrace_fasttrap_probe_ptr)(struct regs *);
2080 extern int (*dtrace_return_probe_ptr)(struct regs *);
2081 extern void (*dtrace_fasttrap_fork_ptr)(proc_t *, proc_t *);
2082 extern void (*dtrace_fasttrap_exec_ptr)(proc_t *);
2083 extern void (*dtrace_fasttrap_exit_ptr)(proc_t *);
2084 extern void dtrace_fasttrap_fork(proc_t *, proc_t *);
2085 
2086 typedef uintptr_t dtrace_icookie_t;
2087 typedef void (*dtrace_xcall_t)(void *);
2088 
2089 extern dtrace_icookie_t dtrace_interrupt_disable(void);
2090 extern void dtrace_interrupt_enable(dtrace_icookie_t);
2091 
2092 extern void dtrace_membar_producer(void);
2093 extern void dtrace_membar_consumer(void);
2094 
2095 extern void (*dtrace_cpu_init)(processorid_t);
2096 extern void (*dtrace_modload)(struct modctl *);
2097 extern void (*dtrace_modunload)(struct modctl *);
2098 extern void (*dtrace_helpers_cleanup)();
2099 extern void (*dtrace_helpers_fork)(proc_t *parent, proc_t *child);
2100 extern void (*dtrace_cpustart_init)();
2101 extern void (*dtrace_cpustart_fini)();
2102 
2103 extern void (*dtrace_kreloc_init)();
2104 extern void (*dtrace_kreloc_fini)();
2105 
2106 extern void (*dtrace_debugger_init)();
2107 extern void (*dtrace_debugger_fini)();
2108 extern dtrace_cacheid_t dtrace_predcache_id;
2109 
2110 extern hrtime_t dtrace_gethrtime(void);
2111 extern void dtrace_sync(void);
2112 extern void dtrace_toxic_ranges(void (*)(uintptr_t, uintptr_t));
2113 extern void dtrace_xcall(processorid_t, dtrace_xcall_t, void *);
2114 extern void dtrace_vpanic(const char *, __va_list);
2115 extern void dtrace_panic(const char *, ...);
2116 
2117 extern int dtrace_safe_defer_signal(void);
2118 extern void dtrace_safe_synchronous_signal(void);
2119 
2120 #if defined(__i386) || defined(__amd64)
2121 extern int dtrace_instr_size(uchar_t *instr);
2122 extern int dtrace_instr_size_isa(uchar_t *, model_t, int *);
2123 extern void dtrace_invop_add(int (*)(uintptr_t, uintptr_t *, uintptr_t));
2124 extern void dtrace_invop_remove(int (*)(uintptr_t, uintptr_t *, uintptr_t));
2125 extern void dtrace_invop_callsite(void);
2126 #endif
2127 
2128 #ifdef __sparc
2129 extern int dtrace_blksuword32(uintptr_t, uint32_t *, int);
2130 extern void dtrace_getfsr(uint64_t *);
2131 #endif
2132 
2133 #define	DTRACE_CPUFLAG_ISSET(flag) \
2134 	(cpu_core[CPU->cpu_id].cpuc_dtrace_flags & (flag))
2135 
2136 #define	DTRACE_CPUFLAG_SET(flag) \
2137 	(cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= (flag))
2138 
2139 #define	DTRACE_CPUFLAG_CLEAR(flag) \
2140 	(cpu_core[CPU->cpu_id].cpuc_dtrace_flags &= ~(flag))
2141 
2142 #endif /* _KERNEL */
2143 
2144 #endif	/* _ASM */
2145 
2146 #if defined(__i386) || defined(__amd64)
2147 
2148 #define	DTRACE_INVOP_PUSHL_EBP		1
2149 #define	DTRACE_INVOP_POPL_EBP		2
2150 #define	DTRACE_INVOP_LEAVE		3
2151 #define	DTRACE_INVOP_NOP		4
2152 #define	DTRACE_INVOP_RET		5
2153 
2154 #endif
2155 
2156 #ifdef	__cplusplus
2157 }
2158 #endif
2159 
2160 #endif	/* _SYS_DTRACE_H */
2161