xref: /titanic_41/usr/src/uts/common/sys/dtrace.h (revision 70025d765b044c6d8594bb965a2247a61e991a99)
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 #define	DIF_OP_XLATE	78		/* xlate xlrindex, rd */
186 #define	DIF_OP_XLARG	79		/* xlarg xlrindex, rd */
187 
188 #define	DIF_INTOFF_MAX		0xffff	/* highest integer table offset */
189 #define	DIF_STROFF_MAX		0xffff	/* highest string table offset */
190 #define	DIF_REGISTER_MAX	0xff	/* highest register number */
191 #define	DIF_VARIABLE_MAX	0xffff	/* highest variable identifier */
192 #define	DIF_SUBROUTINE_MAX	0xffff	/* highest subroutine code */
193 
194 #define	DIF_VAR_ARRAY_MIN	0x0000	/* lowest numbered array variable */
195 #define	DIF_VAR_ARRAY_UBASE	0x0080	/* lowest user-defined array */
196 #define	DIF_VAR_ARRAY_MAX	0x00ff	/* highest numbered array variable */
197 
198 #define	DIF_VAR_OTHER_MIN	0x0100	/* lowest numbered scalar or assc */
199 #define	DIF_VAR_OTHER_UBASE	0x0500	/* lowest user-defined scalar or assc */
200 #define	DIF_VAR_OTHER_MAX	0xffff	/* highest numbered scalar or assc */
201 
202 #define	DIF_VAR_ARGS		0x0000	/* arguments array */
203 #define	DIF_VAR_REGS		0x0001	/* registers array */
204 #define	DIF_VAR_UREGS		0x0002	/* user registers array */
205 #define	DIF_VAR_CURTHREAD	0x0100	/* thread pointer */
206 #define	DIF_VAR_TIMESTAMP	0x0101	/* timestamp */
207 #define	DIF_VAR_VTIMESTAMP	0x0102	/* virtual timestamp */
208 #define	DIF_VAR_IPL		0x0103	/* interrupt priority level */
209 #define	DIF_VAR_EPID		0x0104	/* enabled probe ID */
210 #define	DIF_VAR_ID		0x0105	/* probe ID */
211 #define	DIF_VAR_ARG0		0x0106	/* first argument */
212 #define	DIF_VAR_ARG1		0x0107	/* second argument */
213 #define	DIF_VAR_ARG2		0x0108	/* third argument */
214 #define	DIF_VAR_ARG3		0x0109	/* fourth argument */
215 #define	DIF_VAR_ARG4		0x010a	/* fifth argument */
216 #define	DIF_VAR_ARG5		0x010b	/* sixth argument */
217 #define	DIF_VAR_ARG6		0x010c	/* seventh argument */
218 #define	DIF_VAR_ARG7		0x010d	/* eighth argument */
219 #define	DIF_VAR_ARG8		0x010e	/* ninth argument */
220 #define	DIF_VAR_ARG9		0x010f	/* tenth argument */
221 #define	DIF_VAR_STACKDEPTH	0x0110	/* stack depth */
222 #define	DIF_VAR_CALLER		0x0111	/* caller */
223 #define	DIF_VAR_PROBEPROV	0x0112	/* probe provider */
224 #define	DIF_VAR_PROBEMOD	0x0113	/* probe module */
225 #define	DIF_VAR_PROBEFUNC	0x0114	/* probe function */
226 #define	DIF_VAR_PROBENAME	0x0115	/* probe name */
227 #define	DIF_VAR_PID		0x0116	/* process ID */
228 #define	DIF_VAR_TID		0x0117	/* (per-process) thread ID */
229 #define	DIF_VAR_EXECNAME	0x0118	/* name of executable */
230 #define	DIF_VAR_ZONENAME	0x0119	/* zone name associated with process */
231 #define	DIF_VAR_WALLTIMESTAMP	0x011a	/* wall-clock timestamp */
232 #define	DIF_VAR_USTACKDEPTH	0x011b	/* user-land stack depth */
233 #define	DIF_VAR_UCALLER		0x011c	/* user-level caller */
234 
235 #define	DIF_SUBR_RAND			0
236 #define	DIF_SUBR_MUTEX_OWNED		1
237 #define	DIF_SUBR_MUTEX_OWNER		2
238 #define	DIF_SUBR_MUTEX_TYPE_ADAPTIVE	3
239 #define	DIF_SUBR_MUTEX_TYPE_SPIN	4
240 #define	DIF_SUBR_RW_READ_HELD		5
241 #define	DIF_SUBR_RW_WRITE_HELD		6
242 #define	DIF_SUBR_RW_ISWRITER		7
243 #define	DIF_SUBR_COPYIN			8
244 #define	DIF_SUBR_COPYINSTR		9
245 #define	DIF_SUBR_SPECULATION		10
246 #define	DIF_SUBR_PROGENYOF		11
247 #define	DIF_SUBR_STRLEN			12
248 #define	DIF_SUBR_COPYOUT		13
249 #define	DIF_SUBR_COPYOUTSTR		14
250 #define	DIF_SUBR_ALLOCA			15
251 #define	DIF_SUBR_BCOPY			16
252 #define	DIF_SUBR_COPYINTO		17
253 #define	DIF_SUBR_MSGDSIZE		18
254 #define	DIF_SUBR_MSGSIZE		19
255 #define	DIF_SUBR_GETMAJOR		20
256 #define	DIF_SUBR_GETMINOR		21
257 #define	DIF_SUBR_DDI_PATHNAME		22
258 #define	DIF_SUBR_STRJOIN		23
259 #define	DIF_SUBR_LLTOSTR		24
260 #define	DIF_SUBR_BASENAME		25
261 #define	DIF_SUBR_DIRNAME		26
262 #define	DIF_SUBR_CLEANPATH		27
263 #define	DIF_SUBR_STRCHR			28
264 #define	DIF_SUBR_STRRCHR		29
265 #define	DIF_SUBR_STRSTR			30
266 #define	DIF_SUBR_STRTOK			31
267 #define	DIF_SUBR_SUBSTR			32
268 #define	DIF_SUBR_INDEX			33
269 #define	DIF_SUBR_RINDEX			34
270 
271 #define	DIF_SUBR_MAX			34	/* max subroutine value */
272 
273 typedef uint32_t dif_instr_t;
274 
275 #define	DIF_INSTR_OP(i)			(((i) >> 24) & 0xff)
276 #define	DIF_INSTR_R1(i)			(((i) >> 16) & 0xff)
277 #define	DIF_INSTR_R2(i)			(((i) >>  8) & 0xff)
278 #define	DIF_INSTR_RD(i)			((i) & 0xff)
279 #define	DIF_INSTR_RS(i)			((i) & 0xff)
280 #define	DIF_INSTR_LABEL(i)		((i) & 0xffffff)
281 #define	DIF_INSTR_VAR(i)		(((i) >>  8) & 0xffff)
282 #define	DIF_INSTR_INTEGER(i)		(((i) >>  8) & 0xffff)
283 #define	DIF_INSTR_STRING(i)		(((i) >>  8) & 0xffff)
284 #define	DIF_INSTR_SUBR(i)		(((i) >>  8) & 0xffff)
285 #define	DIF_INSTR_TYPE(i)		(((i) >> 16) & 0xff)
286 #define	DIF_INSTR_XLREF(i)		(((i) >>  8) & 0xffff)
287 
288 #define	DIF_INSTR_FMT(op, r1, r2, d) \
289 	(((op) << 24) | ((r1) << 16) | ((r2) << 8) | (d))
290 
291 #define	DIF_INSTR_NOT(r1, d)		(DIF_INSTR_FMT(DIF_OP_NOT, r1, 0, d))
292 #define	DIF_INSTR_MOV(r1, d)		(DIF_INSTR_FMT(DIF_OP_MOV, r1, 0, d))
293 #define	DIF_INSTR_CMP(op, r1, r2)	(DIF_INSTR_FMT(op, r1, r2, 0))
294 #define	DIF_INSTR_TST(r1)		(DIF_INSTR_FMT(DIF_OP_TST, r1, 0, 0))
295 #define	DIF_INSTR_BRANCH(op, label)	(((op) << 24) | (label))
296 #define	DIF_INSTR_LOAD(op, r1, d)	(DIF_INSTR_FMT(op, r1, 0, d))
297 #define	DIF_INSTR_STORE(op, r1, d)	(DIF_INSTR_FMT(op, r1, 0, d))
298 #define	DIF_INSTR_SETX(i, d)		((DIF_OP_SETX << 24) | ((i) << 8) | (d))
299 #define	DIF_INSTR_SETS(s, d)		((DIF_OP_SETS << 24) | ((s) << 8) | (d))
300 #define	DIF_INSTR_RET(d)		(DIF_INSTR_FMT(DIF_OP_RET, 0, 0, d))
301 #define	DIF_INSTR_NOP			(DIF_OP_NOP << 24)
302 #define	DIF_INSTR_LDA(op, v, r, d)	(DIF_INSTR_FMT(op, v, r, d))
303 #define	DIF_INSTR_LDV(op, v, d)		(((op) << 24) | ((v) << 8) | (d))
304 #define	DIF_INSTR_STV(op, v, rs)	(((op) << 24) | ((v) << 8) | (rs))
305 #define	DIF_INSTR_CALL(s, d)		((DIF_OP_CALL << 24) | ((s) << 8) | (d))
306 #define	DIF_INSTR_PUSHTS(op, t, r2, rs)	(DIF_INSTR_FMT(op, t, r2, rs))
307 #define	DIF_INSTR_POPTS			(DIF_OP_POPTS << 24)
308 #define	DIF_INSTR_FLUSHTS		(DIF_OP_FLUSHTS << 24)
309 #define	DIF_INSTR_ALLOCS(r1, d)		(DIF_INSTR_FMT(DIF_OP_ALLOCS, r1, 0, d))
310 #define	DIF_INSTR_COPYS(r1, r2, d)	(DIF_INSTR_FMT(DIF_OP_COPYS, r1, r2, d))
311 #define	DIF_INSTR_XLATE(op, r, d)	(((op) << 24) | ((r) << 8) | (d))
312 
313 #define	DIF_REG_R0	0		/* %r0 is always set to zero */
314 
315 /*
316  * A DTrace Intermediate Format Type (DIF Type) is used to represent the types
317  * of variables, function and associative array arguments, and the return type
318  * for each DIF object (shown below).  It contains a description of the type,
319  * its size in bytes, and a module identifier.
320  */
321 typedef struct dtrace_diftype {
322 	uint8_t dtdt_kind;		/* type kind (see below) */
323 	uint8_t dtdt_ckind;		/* type kind in CTF */
324 	uint8_t dtdt_flags;		/* type flags (see below) */
325 	uint8_t dtdt_pad;		/* reserved for future use */
326 	uint32_t dtdt_size;		/* type size in bytes (unless string) */
327 } dtrace_diftype_t;
328 
329 #define	DIF_TYPE_CTF		0	/* type is a CTF type */
330 #define	DIF_TYPE_STRING		1	/* type is a D string */
331 
332 #define	DIF_TF_BYREF		0x1	/* type is passed by reference */
333 
334 /*
335  * A DTrace Intermediate Format variable record is used to describe each of the
336  * variables referenced by a given DIF object.  It contains an integer variable
337  * identifier along with variable scope and properties, as shown below.  The
338  * size of this structure must be sizeof (int) aligned.
339  */
340 typedef struct dtrace_difv {
341 	uint32_t dtdv_name;		/* variable name index in dtdo_strtab */
342 	uint32_t dtdv_id;		/* variable reference identifier */
343 	uint8_t dtdv_kind;		/* variable kind (see below) */
344 	uint8_t dtdv_scope;		/* variable scope (see below) */
345 	uint16_t dtdv_flags;		/* variable flags (see below) */
346 	dtrace_diftype_t dtdv_type;	/* variable type (see above) */
347 } dtrace_difv_t;
348 
349 #define	DIFV_KIND_ARRAY		0	/* variable is an array of quantities */
350 #define	DIFV_KIND_SCALAR	1	/* variable is a scalar quantity */
351 
352 #define	DIFV_SCOPE_GLOBAL	0	/* variable has global scope */
353 #define	DIFV_SCOPE_THREAD	1	/* variable has thread scope */
354 #define	DIFV_SCOPE_LOCAL	2	/* variable has local scope */
355 
356 #define	DIFV_F_REF		0x1	/* variable is referenced by DIFO */
357 #define	DIFV_F_MOD		0x2	/* variable is written by DIFO */
358 
359 /*
360  * DTrace Actions
361  *
362  * The upper byte determines the class of the action; the low bytes determines
363  * the specific action within that class.  The classes of actions are as
364  * follows:
365  *
366  *   [ no class ]                  <= May record process- or kernel-related data
367  *   DTRACEACT_PROC                <= Only records process-related data
368  *   DTRACEACT_PROC_DESTRUCTIVE    <= Potentially destructive to processes
369  *   DTRACEACT_KERNEL              <= Only records kernel-related data
370  *   DTRACEACT_KERNEL_DESTRUCTIVE  <= Potentially destructive to the kernel
371  *   DTRACEACT_SPECULATIVE         <= Speculation-related action
372  *   DTRACEACT_AGGREGATION         <= Aggregating action
373  */
374 #define	DTRACEACT_NONE			0	/* no action */
375 #define	DTRACEACT_DIFEXPR		1	/* action is DIF expression */
376 #define	DTRACEACT_EXIT			2	/* exit() action */
377 #define	DTRACEACT_PRINTF		3	/* printf() action */
378 #define	DTRACEACT_PRINTA		4	/* printa() action */
379 #define	DTRACEACT_LIBACT		5	/* library-controlled action */
380 
381 #define	DTRACEACT_PROC			0x0100
382 #define	DTRACEACT_USTACK		(DTRACEACT_PROC + 1)
383 #define	DTRACEACT_JSTACK		(DTRACEACT_PROC + 2)
384 #define	DTRACEACT_USYM			(DTRACEACT_PROC + 3)
385 #define	DTRACEACT_UMOD			(DTRACEACT_PROC + 4)
386 #define	DTRACEACT_UADDR			(DTRACEACT_PROC + 5)
387 
388 #define	DTRACEACT_PROC_DESTRUCTIVE	0x0200
389 #define	DTRACEACT_STOP			(DTRACEACT_PROC_DESTRUCTIVE + 1)
390 #define	DTRACEACT_RAISE			(DTRACEACT_PROC_DESTRUCTIVE + 2)
391 #define	DTRACEACT_SYSTEM		(DTRACEACT_PROC_DESTRUCTIVE + 3)
392 #define	DTRACEACT_FREOPEN		(DTRACEACT_PROC_DESTRUCTIVE + 4)
393 
394 #define	DTRACEACT_PROC_CONTROL		0x0300
395 
396 #define	DTRACEACT_KERNEL		0x0400
397 #define	DTRACEACT_STACK			(DTRACEACT_KERNEL + 1)
398 #define	DTRACEACT_SYM			(DTRACEACT_KERNEL + 2)
399 #define	DTRACEACT_MOD			(DTRACEACT_KERNEL + 3)
400 
401 #define	DTRACEACT_KERNEL_DESTRUCTIVE	0x0500
402 #define	DTRACEACT_BREAKPOINT		(DTRACEACT_KERNEL_DESTRUCTIVE + 1)
403 #define	DTRACEACT_PANIC			(DTRACEACT_KERNEL_DESTRUCTIVE + 2)
404 #define	DTRACEACT_CHILL			(DTRACEACT_KERNEL_DESTRUCTIVE + 3)
405 
406 #define	DTRACEACT_SPECULATIVE		0x0600
407 #define	DTRACEACT_SPECULATE		(DTRACEACT_SPECULATIVE + 1)
408 #define	DTRACEACT_COMMIT		(DTRACEACT_SPECULATIVE + 2)
409 #define	DTRACEACT_DISCARD		(DTRACEACT_SPECULATIVE + 3)
410 
411 #define	DTRACEACT_CLASS(x)		((x) & 0xff00)
412 
413 #define	DTRACEACT_ISDESTRUCTIVE(x)	\
414 	(DTRACEACT_CLASS(x) == DTRACEACT_PROC_DESTRUCTIVE || \
415 	DTRACEACT_CLASS(x) == DTRACEACT_KERNEL_DESTRUCTIVE)
416 
417 #define	DTRACEACT_ISSPECULATIVE(x)	\
418 	(DTRACEACT_CLASS(x) == DTRACEACT_SPECULATIVE)
419 
420 #define	DTRACEACT_ISPRINTFLIKE(x)	\
421 	((x) == DTRACEACT_PRINTF || (x) == DTRACEACT_PRINTA || \
422 	(x) == DTRACEACT_SYSTEM || (x) == DTRACEACT_FREOPEN)
423 
424 /*
425  * DTrace Aggregating Actions
426  *
427  * These are functions f(x) for which the following is true:
428  *
429  *    f(f(x_0) U f(x_1) U ... U f(x_n)) = f(x_0 U x_1 U ... U x_n)
430  *
431  * where x_n is a set of arbitrary data.  Aggregating actions are in their own
432  * DTrace action class, DTTRACEACT_AGGREGATION.  The macros provided here allow
433  * for easier processing of the aggregation argument and data payload for a few
434  * aggregating actions (notably:  quantize(), lquantize(), and ustack()).
435  */
436 #define	DTRACEACT_AGGREGATION		0x0700
437 #define	DTRACEAGG_COUNT			(DTRACEACT_AGGREGATION + 1)
438 #define	DTRACEAGG_MIN			(DTRACEACT_AGGREGATION + 2)
439 #define	DTRACEAGG_MAX			(DTRACEACT_AGGREGATION + 3)
440 #define	DTRACEAGG_AVG			(DTRACEACT_AGGREGATION + 4)
441 #define	DTRACEAGG_SUM			(DTRACEACT_AGGREGATION + 5)
442 #define	DTRACEAGG_STDDEV		(DTRACEACT_AGGREGATION + 6)
443 #define	DTRACEAGG_QUANTIZE		(DTRACEACT_AGGREGATION + 7)
444 #define	DTRACEAGG_LQUANTIZE		(DTRACEACT_AGGREGATION + 8)
445 
446 #define	DTRACEACT_ISAGG(x)		\
447 	(DTRACEACT_CLASS(x) == DTRACEACT_AGGREGATION)
448 
449 #define	DTRACE_QUANTIZE_NBUCKETS	\
450 	(((sizeof (uint64_t) * NBBY) - 1) * 2 + 1)
451 
452 #define	DTRACE_QUANTIZE_ZEROBUCKET	((sizeof (uint64_t) * NBBY) - 1)
453 
454 #define	DTRACE_QUANTIZE_BUCKETVAL(buck)					\
455 	(int64_t)((buck) < DTRACE_QUANTIZE_ZEROBUCKET ?			\
456 	-(1LL << (DTRACE_QUANTIZE_ZEROBUCKET - 1 - (buck))) :		\
457 	(buck) == DTRACE_QUANTIZE_ZEROBUCKET ? 0 :			\
458 	1LL << ((buck) - DTRACE_QUANTIZE_ZEROBUCKET - 1))
459 
460 #define	DTRACE_LQUANTIZE_STEPSHIFT		48
461 #define	DTRACE_LQUANTIZE_STEPMASK		((uint64_t)UINT16_MAX << 48)
462 #define	DTRACE_LQUANTIZE_LEVELSHIFT		32
463 #define	DTRACE_LQUANTIZE_LEVELMASK		((uint64_t)UINT16_MAX << 32)
464 #define	DTRACE_LQUANTIZE_BASESHIFT		0
465 #define	DTRACE_LQUANTIZE_BASEMASK		UINT32_MAX
466 
467 #define	DTRACE_LQUANTIZE_STEP(x)		\
468 	(uint16_t)(((x) & DTRACE_LQUANTIZE_STEPMASK) >> \
469 	DTRACE_LQUANTIZE_STEPSHIFT)
470 
471 #define	DTRACE_LQUANTIZE_LEVELS(x)		\
472 	(uint16_t)(((x) & DTRACE_LQUANTIZE_LEVELMASK) >> \
473 	DTRACE_LQUANTIZE_LEVELSHIFT)
474 
475 #define	DTRACE_LQUANTIZE_BASE(x)		\
476 	(int32_t)(((x) & DTRACE_LQUANTIZE_BASEMASK) >> \
477 	DTRACE_LQUANTIZE_BASESHIFT)
478 
479 #define	DTRACE_USTACK_NFRAMES(x)	(uint32_t)((x) & UINT32_MAX)
480 #define	DTRACE_USTACK_STRSIZE(x)	(uint32_t)((x) >> 32)
481 #define	DTRACE_USTACK_ARG(x, y)		\
482 	((((uint64_t)(y)) << 32) | ((x) & UINT32_MAX))
483 
484 #ifndef _LP64
485 #ifndef _LITTLE_ENDIAN
486 #define	DTRACE_PTR(type, name)	uint32_t name##pad; type *name
487 #else
488 #define	DTRACE_PTR(type, name)	type *name; uint32_t name##pad
489 #endif
490 #else
491 #define	DTRACE_PTR(type, name)	type *name
492 #endif
493 
494 /*
495  * DTrace Object Format (DOF)
496  *
497  * DTrace programs can be persistently encoded in the DOF format so that they
498  * may be embedded in other programs (for example, in an ELF file) or in the
499  * dtrace driver configuration file for use in anonymous tracing.  The DOF
500  * format is versioned and extensible so that it can be revised and so that
501  * internal data structures can be modified or extended compatibly.  All DOF
502  * structures use fixed-size types, so the 32-bit and 64-bit representations
503  * are identical and consumers can use either data model transparently.
504  *
505  * The file layout is structured as follows:
506  *
507  * +---------------+-------------------+----- ... ----+---- ... ------+
508  * |   dof_hdr_t   |  dof_sec_t[ ... ] |   loadable   | non-loadable  |
509  * | (file header) | (section headers) | section data | section data  |
510  * +---------------+-------------------+----- ... ----+---- ... ------+
511  * |<------------ dof_hdr.dofh_loadsz --------------->|               |
512  * |<------------ dof_hdr.dofh_filesz ------------------------------->|
513  *
514  * The file header stores meta-data including a magic number, data model for
515  * the instrumentation, data encoding, and properties of the DIF code within.
516  * The header describes its own size and the size of the section headers.  By
517  * convention, an array of section headers follows the file header, and then
518  * the data for all loadable sections and unloadable sections.  This permits
519  * consumer code to easily download the headers and all loadable data into the
520  * DTrace driver in one contiguous chunk, omitting other extraneous sections.
521  *
522  * The section headers describe the size, offset, alignment, and section type
523  * for each section.  Sections are described using a set of #defines that tell
524  * the consumer what kind of data is expected.  Sections can contain links to
525  * other sections by storing a dof_secidx_t, an index into the section header
526  * array, inside of the section data structures.  The section header includes
527  * an entry size so that sections with data arrays can grow their structures.
528  *
529  * The DOF data itself can contain many snippets of DIF (i.e. >1 DIFOs), which
530  * are represented themselves as a collection of related DOF sections.  This
531  * permits us to change the set of sections associated with a DIFO over time,
532  * and also permits us to encode DIFOs that contain different sets of sections.
533  * When a DOF section wants to refer to a DIFO, it stores the dof_secidx_t of a
534  * section of type DOF_SECT_DIFOHDR.  This section's data is then an array of
535  * dof_secidx_t's which in turn denote the sections associated with this DIFO.
536  *
537  * This loose coupling of the file structure (header and sections) to the
538  * structure of the DTrace program itself (ECB descriptions, action
539  * descriptions, and DIFOs) permits activities such as relocation processing
540  * to occur in a single pass without having to understand D program structure.
541  *
542  * Finally, strings are always stored in ELF-style string tables along with a
543  * string table section index and string table offset.  Therefore strings in
544  * DOF are always arbitrary-length and not bound to the current implementation.
545  */
546 
547 #define	DOF_ID_SIZE	16	/* total size of dofh_ident[] in bytes */
548 
549 typedef struct dof_hdr {
550 	uint8_t dofh_ident[DOF_ID_SIZE]; /* identification bytes (see below) */
551 	uint32_t dofh_flags;		/* file attribute flags (if any) */
552 	uint32_t dofh_hdrsize;		/* size of file header in bytes */
553 	uint32_t dofh_secsize;		/* size of section header in bytes */
554 	uint32_t dofh_secnum;		/* number of section headers */
555 	uint64_t dofh_secoff;		/* file offset of section headers */
556 	uint64_t dofh_loadsz;		/* file size of loadable portion */
557 	uint64_t dofh_filesz;		/* file size of entire DOF file */
558 	uint64_t dofh_pad;		/* reserved for future use */
559 } dof_hdr_t;
560 
561 #define	DOF_ID_MAG0	0	/* first byte of magic number */
562 #define	DOF_ID_MAG1	1	/* second byte of magic number */
563 #define	DOF_ID_MAG2	2	/* third byte of magic number */
564 #define	DOF_ID_MAG3	3	/* fourth byte of magic number */
565 #define	DOF_ID_MODEL	4	/* DOF data model (see below) */
566 #define	DOF_ID_ENCODING	5	/* DOF data encoding (see below) */
567 #define	DOF_ID_VERSION	6	/* DOF file format major version (see below) */
568 #define	DOF_ID_DIFVERS	7	/* DIF instruction set version */
569 #define	DOF_ID_DIFIREG	8	/* DIF integer registers used by compiler */
570 #define	DOF_ID_DIFTREG	9	/* DIF tuple registers used by compiler */
571 #define	DOF_ID_PAD	10	/* start of padding bytes (all zeroes) */
572 
573 #define	DOF_MAG_MAG0	0x7F	/* DOF_ID_MAG[0-3] */
574 #define	DOF_MAG_MAG1	'D'
575 #define	DOF_MAG_MAG2	'O'
576 #define	DOF_MAG_MAG3	'F'
577 
578 #define	DOF_MAG_STRING	"\177DOF"
579 #define	DOF_MAG_STRLEN	4
580 
581 #define	DOF_MODEL_NONE	0	/* DOF_ID_MODEL */
582 #define	DOF_MODEL_ILP32	1
583 #define	DOF_MODEL_LP64	2
584 
585 #ifdef _LP64
586 #define	DOF_MODEL_NATIVE	DOF_MODEL_LP64
587 #else
588 #define	DOF_MODEL_NATIVE	DOF_MODEL_ILP32
589 #endif
590 
591 #define	DOF_ENCODE_NONE	0	/* DOF_ID_ENCODING */
592 #define	DOF_ENCODE_LSB	1
593 #define	DOF_ENCODE_MSB	2
594 
595 #ifdef _BIG_ENDIAN
596 #define	DOF_ENCODE_NATIVE	DOF_ENCODE_MSB
597 #else
598 #define	DOF_ENCODE_NATIVE	DOF_ENCODE_LSB
599 #endif
600 
601 #define	DOF_VERSION_1	1	/* DOF_ID_VERSION */
602 #define	DOF_VERSION	DOF_VERSION_1
603 
604 #define	DOF_FL_VALID	0	/* mask of all valid dofh_flags bits */
605 
606 typedef uint32_t dof_secidx_t;	/* section header table index type */
607 typedef uint32_t dof_stridx_t;	/* string table index type */
608 
609 #define	DOF_SECIDX_NONE	(-1U)	/* null value for section indices */
610 #define	DOF_STRIDX_NONE	(-1U)	/* null value for string indices */
611 
612 typedef struct dof_sec {
613 	uint32_t dofs_type;	/* section type (see below) */
614 	uint32_t dofs_align;	/* section data memory alignment */
615 	uint32_t dofs_flags;	/* section flags (if any) */
616 	uint32_t dofs_entsize;	/* size of section entry (if table) */
617 	uint64_t dofs_offset;	/* offset of section data within file */
618 	uint64_t dofs_size;	/* size of section data in bytes */
619 } dof_sec_t;
620 
621 #define	DOF_SECT_NONE		0	/* null section */
622 #define	DOF_SECT_COMMENTS	1	/* compiler comments */
623 #define	DOF_SECT_SOURCE		2	/* D program source code */
624 #define	DOF_SECT_ECBDESC	3	/* dof_ecbdesc_t */
625 #define	DOF_SECT_PROBEDESC	4	/* dof_probedesc_t */
626 #define	DOF_SECT_ACTDESC	5	/* dof_actdesc_t array */
627 #define	DOF_SECT_DIFOHDR	6	/* dof_difohdr_t (variable length) */
628 #define	DOF_SECT_DIF		7	/* uint32_t array of byte code */
629 #define	DOF_SECT_STRTAB		8	/* string table */
630 #define	DOF_SECT_VARTAB		9	/* dtrace_difv_t array */
631 #define	DOF_SECT_RELTAB		10	/* dof_relodesc_t array */
632 #define	DOF_SECT_TYPTAB		11	/* dtrace_diftype_t array */
633 #define	DOF_SECT_URELHDR	12	/* dof_relohdr_t (user relocations) */
634 #define	DOF_SECT_KRELHDR	13	/* dof_relohdr_t (kernel relocations) */
635 #define	DOF_SECT_OPTDESC	14	/* dof_optdesc_t array */
636 #define	DOF_SECT_PROVIDER	15	/* dof_provider_t */
637 #define	DOF_SECT_PROBES		16	/* dof_probe_t array */
638 #define	DOF_SECT_PRARGS		17	/* uint8_t array (probe arg mappings) */
639 #define	DOF_SECT_PROFFS		18	/* uint32_t array (probe arg offsets) */
640 #define	DOF_SECT_INTTAB		19	/* uint64_t array */
641 #define	DOF_SECT_UTSNAME	20	/* struct utsname */
642 #define	DOF_SECT_XLTAB		21	/* dof_xlref_t array */
643 #define	DOF_SECT_XLMEMBERS	22	/* dof_xlmember_t array */
644 #define	DOF_SECT_XLIMPORT	23	/* dof_xlator_t */
645 #define	DOF_SECT_XLEXPORT	24	/* dof_xlator_t */
646 #define	DOF_SECT_PREXPORT	25	/* dof_secidx_t array (exported objs) */
647 
648 #define	DOF_SECF_LOAD		1	/* section should be loaded */
649 
650 typedef struct dof_ecbdesc {
651 	dof_secidx_t dofe_probes;	/* link to DOF_SECT_PROBEDESC */
652 	dof_secidx_t dofe_pred;		/* link to DOF_SECT_DIFOHDR */
653 	dof_secidx_t dofe_actions;	/* link to DOF_SECT_ACTDESC */
654 	uint32_t dofe_pad;		/* reserved for future use */
655 	uint64_t dofe_uarg;		/* user-supplied library argument */
656 } dof_ecbdesc_t;
657 
658 typedef struct dof_probedesc {
659 	dof_secidx_t dofp_strtab;	/* link to DOF_SECT_STRTAB section */
660 	dof_stridx_t dofp_provider;	/* provider string */
661 	dof_stridx_t dofp_mod;		/* module string */
662 	dof_stridx_t dofp_func;		/* function string */
663 	dof_stridx_t dofp_name;		/* name string */
664 	uint32_t dofp_id;		/* probe identifier (or zero) */
665 } dof_probedesc_t;
666 
667 typedef struct dof_actdesc {
668 	dof_secidx_t dofa_difo;		/* link to DOF_SECT_DIFOHDR */
669 	dof_secidx_t dofa_strtab;	/* link to DOF_SECT_STRTAB section */
670 	uint32_t dofa_kind;		/* action kind (DTRACEACT_* constant) */
671 	uint32_t dofa_ntuple;		/* number of subsequent tuple actions */
672 	uint64_t dofa_arg;		/* kind-specific argument */
673 	uint64_t dofa_uarg;		/* user-supplied argument */
674 } dof_actdesc_t;
675 
676 typedef struct dof_difohdr {
677 	dtrace_diftype_t dofd_rtype;	/* return type for this fragment */
678 	dof_secidx_t dofd_links[1];	/* variable length array of indices */
679 } dof_difohdr_t;
680 
681 typedef struct dof_relohdr {
682 	dof_secidx_t dofr_strtab;	/* link to DOF_SECT_STRTAB for names */
683 	dof_secidx_t dofr_relsec;	/* link to DOF_SECT_RELTAB for relos */
684 	dof_secidx_t dofr_tgtsec;	/* link to section we are relocating */
685 } dof_relohdr_t;
686 
687 typedef struct dof_relodesc {
688 	dof_stridx_t dofr_name;		/* string name of relocation symbol */
689 	uint32_t dofr_type;		/* relo type (DOF_RELO_* constant) */
690 	uint64_t dofr_offset;		/* byte offset for relocation */
691 	uint64_t dofr_data;		/* additional type-specific data */
692 } dof_relodesc_t;
693 
694 #define	DOF_RELO_NONE	0		/* empty relocation entry */
695 #define	DOF_RELO_SETX	1		/* relocate setx value */
696 
697 typedef struct dof_optdesc {
698 	uint32_t dofo_option;		/* option identifier */
699 	dof_secidx_t dofo_strtab;	/* string table, if string option */
700 	uint64_t dofo_value;		/* option value or string index */
701 } dof_optdesc_t;
702 
703 typedef uint32_t dof_attr_t;		/* encoded stability attributes */
704 
705 #define	DOF_ATTR(n, d, c)	(((n) << 24) | ((d) << 16) | ((c) << 8))
706 #define	DOF_ATTR_NAME(a)	(((a) >> 24) & 0xff)
707 #define	DOF_ATTR_DATA(a)	(((a) >> 16) & 0xff)
708 #define	DOF_ATTR_CLASS(a)	(((a) >>  8) & 0xff)
709 
710 typedef struct dof_provider {
711 	dof_secidx_t dofpv_strtab;	/* link to DOF_SECT_STRTAB section */
712 	dof_secidx_t dofpv_probes;	/* link to DOF_SECT_PROBES section */
713 	dof_secidx_t dofpv_prargs;	/* link to DOF_SECT_PRARGS section */
714 	dof_secidx_t dofpv_proffs;	/* link to DOF_SECT_PROFFS section */
715 	dof_stridx_t dofpv_name;	/* provider name string */
716 	dof_attr_t dofpv_provattr;	/* provider attributes */
717 	dof_attr_t dofpv_modattr;	/* module attributes */
718 	dof_attr_t dofpv_funcattr;	/* function attributes */
719 	dof_attr_t dofpv_nameattr;	/* name attributes */
720 	dof_attr_t dofpv_argsattr;	/* args attributes */
721 } dof_provider_t;
722 
723 typedef struct dof_probe {
724 	uint64_t dofpr_addr;		/* probe base address or offset */
725 	dof_stridx_t dofpr_func;	/* probe function string */
726 	dof_stridx_t dofpr_name;	/* probe name string */
727 	dof_stridx_t dofpr_nargv;	/* native argument type strings */
728 	dof_stridx_t dofpr_xargv;	/* translated argument type strings */
729 	uint32_t dofpr_argidx;		/* index of first argument mapping */
730 	uint32_t dofpr_offidx;		/* index of first offset entry */
731 	uint8_t dofpr_nargc;		/* native argument count */
732 	uint8_t dofpr_xargc;		/* translated argument count */
733 	uint16_t dofpr_noffs;		/* number of offset entries for probe */
734 	uint32_t dofpr_pad;		/* reserved for future use */
735 } dof_probe_t;
736 
737 typedef struct dof_xlator {
738 	dof_secidx_t dofxl_members;	/* link to DOF_SECT_XLMEMBERS section */
739 	dof_secidx_t dofxl_strtab;	/* link to DOF_SECT_STRTAB section */
740 	dof_stridx_t dofxl_argv;	/* input parameter type strings */
741 	uint32_t dofxl_argc;		/* input parameter list length */
742 	dof_stridx_t dofxl_type;	/* output type string name */
743 	dof_attr_t dofxl_attr;		/* output stability attributes */
744 } dof_xlator_t;
745 
746 typedef struct dof_xlmember {
747 	dof_secidx_t dofxm_difo;	/* member link to DOF_SECT_DIFOHDR */
748 	dof_stridx_t dofxm_name;	/* member name */
749 	dtrace_diftype_t dofxm_type;	/* member type */
750 } dof_xlmember_t;
751 
752 typedef struct dof_xlref {
753 	dof_secidx_t dofxr_xlator;	/* link to DOF_SECT_XLATORS section */
754 	uint32_t dofxr_member;		/* index of referenced dof_xlmember */
755 	uint32_t dofxr_argn;		/* index of argument for DIF_OP_XLARG */
756 } dof_xlref_t;
757 
758 /*
759  * DTrace Intermediate Format Object (DIFO)
760  *
761  * A DIFO is used to store the compiled DIF for a D expression, its return
762  * type, and its string and variable tables.  The string table is a single
763  * buffer of character data into which sets instructions and variable
764  * references can reference strings using a byte offset.  The variable table
765  * is an array of dtrace_difv_t structures that describe the name and type of
766  * each variable and the id used in the DIF code.  This structure is described
767  * above in the DIF section of this header file.  The DIFO is used at both
768  * user-level (in the library) and in the kernel, but the structure is never
769  * passed between the two: the DOF structures form the only interface.  As a
770  * result, the definition can change depending on the presence of _KERNEL.
771  */
772 typedef struct dtrace_difo {
773 	dif_instr_t *dtdo_buf;		/* instruction buffer */
774 	uint64_t *dtdo_inttab;		/* integer table (optional) */
775 	char *dtdo_strtab;		/* string table (optional) */
776 	dtrace_difv_t *dtdo_vartab;	/* variable table (optional) */
777 	uint_t dtdo_len;		/* length of instruction buffer */
778 	uint_t dtdo_intlen;		/* length of integer table */
779 	uint_t dtdo_strlen;		/* length of string table */
780 	uint_t dtdo_varlen;		/* length of variable table */
781 	dtrace_diftype_t dtdo_rtype;	/* return type */
782 	uint_t dtdo_refcnt;		/* owner reference count */
783 	uint_t dtdo_destructive;	/* invokes destructive subroutines */
784 #ifndef _KERNEL
785 	dof_relodesc_t *dtdo_kreltab;	/* kernel relocations */
786 	dof_relodesc_t *dtdo_ureltab;	/* user relocations */
787 	struct dt_node **dtdo_xlmtab;	/* translator references */
788 	uint_t dtdo_krelen;		/* length of krelo table */
789 	uint_t dtdo_urelen;		/* length of urelo table */
790 	uint_t dtdo_xlmlen;		/* length of translator table */
791 #endif
792 } dtrace_difo_t;
793 
794 /*
795  * DTrace Enabling Description Structures
796  *
797  * When DTrace is tracking the description of a DTrace enabling entity (probe,
798  * predicate, action, ECB, record, etc.), it does so in a description
799  * structure.  These structures all end in "desc", and are used at both
800  * user-level and in the kernel -- but (with the exception of
801  * dtrace_probedesc_t) they are never passed between them.  Typically,
802  * user-level will use the description structures when assembling an enabling.
803  * It will then distill those description structures into a DOF object (see
804  * above), and send it into the kernel.  The kernel will again use the
805  * description structures to create a description of the enabling as it reads
806  * the DOF.  When the description is complete, the enabling will be actually
807  * created -- turning it into the structures that represent the enabling
808  * instead of merely describing it.  Not surprisingly, the description
809  * structures bear a strong resemblance to the DOF structures that act as their
810  * conduit.
811  */
812 struct dtrace_predicate;
813 
814 typedef struct dtrace_probedesc {
815 	dtrace_id_t dtpd_id;			/* probe identifier */
816 	char dtpd_provider[DTRACE_PROVNAMELEN]; /* probe provider name */
817 	char dtpd_mod[DTRACE_MODNAMELEN];	/* probe module name */
818 	char dtpd_func[DTRACE_FUNCNAMELEN];	/* probe function name */
819 	char dtpd_name[DTRACE_NAMELEN];		/* probe name */
820 } dtrace_probedesc_t;
821 
822 typedef struct dtrace_repldesc {
823 	dtrace_probedesc_t dtrpd_match;		/* probe descr. to match */
824 	dtrace_probedesc_t dtrpd_create;	/* probe descr. to create */
825 } dtrace_repldesc_t;
826 
827 typedef struct dtrace_preddesc {
828 	dtrace_difo_t *dtpdd_difo;		/* pointer to DIF object */
829 	struct dtrace_predicate *dtpdd_predicate; /* pointer to predicate */
830 } dtrace_preddesc_t;
831 
832 typedef struct dtrace_actdesc {
833 	dtrace_difo_t *dtad_difo;		/* pointer to DIF object */
834 	struct dtrace_actdesc *dtad_next;	/* next action */
835 	dtrace_actkind_t dtad_kind;		/* kind of action */
836 	uint32_t dtad_ntuple;			/* number in tuple */
837 	uint64_t dtad_arg;			/* action argument */
838 	uint64_t dtad_uarg;			/* user argument */
839 	int dtad_refcnt;			/* reference count */
840 } dtrace_actdesc_t;
841 
842 typedef struct dtrace_ecbdesc {
843 	dtrace_actdesc_t *dted_action;		/* action description(s) */
844 	dtrace_preddesc_t dted_pred;		/* predicate description */
845 	dtrace_probedesc_t dted_probe;		/* probe description */
846 	uint64_t dted_uarg;			/* library argument */
847 	int dted_refcnt;			/* reference count */
848 } dtrace_ecbdesc_t;
849 
850 /*
851  * DTrace Metadata Description Structures
852  *
853  * DTrace separates the trace data stream from the metadata stream.  The only
854  * metadata tokens placed in the data stream are enabled probe identifiers
855  * (EPIDs) or (in the case of aggregations) aggregation identifiers.  In order
856  * to determine the structure of the data, DTrace consumers pass the token to
857  * the kernel, and receive in return a corresponding description of the enabled
858  * probe (via the dtrace_eprobedesc structure) or the aggregation (via the
859  * dtrace_aggdesc structure).  Both of these structures are expressed in terms
860  * of record descriptions (via the dtrace_recdesc structure) that describe the
861  * exact structure of the data.  Some record descriptions may also contain a
862  * format identifier; this additional bit of metadata can be retrieved from the
863  * kernel, for which a format description is returned via the dtrace_fmtdesc
864  * structure.  Note that all four of these structures must be bitness-neutral
865  * to allow for a 32-bit DTrace consumer on a 64-bit kernel.
866  */
867 typedef struct dtrace_recdesc {
868 	dtrace_actkind_t dtrd_action;		/* kind of action */
869 	uint32_t dtrd_size;			/* size of record */
870 	uint32_t dtrd_offset;			/* offset in ECB's data */
871 	uint16_t dtrd_alignment;		/* required alignment */
872 	uint16_t dtrd_format;			/* format, if any */
873 	uint64_t dtrd_arg;			/* action argument */
874 	uint64_t dtrd_uarg;			/* user argument */
875 } dtrace_recdesc_t;
876 
877 typedef struct dtrace_eprobedesc {
878 	dtrace_epid_t dtepd_epid;		/* enabled probe ID */
879 	dtrace_id_t dtepd_probeid;		/* probe ID */
880 	uint64_t dtepd_uarg;			/* library argument */
881 	uint32_t dtepd_size;			/* total size */
882 	int dtepd_nrecs;			/* number of records */
883 	dtrace_recdesc_t dtepd_rec[1];		/* records themselves */
884 } dtrace_eprobedesc_t;
885 
886 typedef struct dtrace_aggdesc {
887 	DTRACE_PTR(char, dtagd_name);		/* not filled in by kernel */
888 	int dtagd_flags;			/* not filled in by kernel */
889 	dtrace_aggid_t dtagd_id;		/* aggregation ID */
890 	dtrace_epid_t dtagd_epid;		/* enabled probe ID */
891 	uint32_t dtagd_size;			/* size in bytes */
892 	int dtagd_nrecs;			/* number of records */
893 	uint32_t dtagd_pad;			/* explicit padding */
894 	dtrace_recdesc_t dtagd_rec[1];		/* record descriptions */
895 } dtrace_aggdesc_t;
896 
897 typedef struct dtrace_fmtdesc {
898 	DTRACE_PTR(char, dtfd_string);		/* format string */
899 	int dtfd_length;			/* length of format string */
900 	uint16_t dtfd_format;			/* format identifier */
901 } dtrace_fmtdesc_t;
902 
903 #define	DTRACE_SIZEOF_EPROBEDESC(desc)				\
904 	(sizeof (dtrace_eprobedesc_t) + ((desc)->dtepd_nrecs ?	\
905 	(((desc)->dtepd_nrecs - 1) * sizeof (dtrace_recdesc_t)) : 0))
906 
907 #define	DTRACE_SIZEOF_AGGDESC(desc)				\
908 	(sizeof (dtrace_aggdesc_t) + ((desc)->dtagd_nrecs ?	\
909 	(((desc)->dtagd_nrecs - 1) * sizeof (dtrace_recdesc_t)) : 0))
910 
911 /*
912  * DTrace Option Interface
913  *
914  * Run-time DTrace options are set and retrieved via DOF_SECT_OPTDESC sections
915  * in a DOF image.  The dof_optdesc structure contains an option identifier and
916  * an option value.  The valid option identifiers are found below; the mapping
917  * between option identifiers and option identifying strings is maintained at
918  * user-level.  Note that the value of DTRACEOPT_UNSET is such that all of the
919  * following are potentially valid option values:  all positive integers, zero
920  * and negative one.  Some options (notably "bufpolicy" and "bufresize") take
921  * predefined tokens as their values; these are defined with
922  * DTRACEOPT_{option}_{token}.
923  */
924 #define	DTRACEOPT_BUFSIZE	0	/* buffer size */
925 #define	DTRACEOPT_BUFPOLICY	1	/* buffer policy */
926 #define	DTRACEOPT_DYNVARSIZE	2	/* dynamic variable size */
927 #define	DTRACEOPT_AGGSIZE	3	/* aggregation size */
928 #define	DTRACEOPT_SPECSIZE	4	/* speculation size */
929 #define	DTRACEOPT_NSPEC		5	/* number of speculations */
930 #define	DTRACEOPT_STRSIZE	6	/* string size */
931 #define	DTRACEOPT_CLEANRATE	7	/* dynvar cleaning rate */
932 #define	DTRACEOPT_CPU		8	/* CPU to trace */
933 #define	DTRACEOPT_BUFRESIZE	9	/* buffer resizing policy */
934 #define	DTRACEOPT_GRABANON	10	/* grab anonymous state, if any */
935 #define	DTRACEOPT_FLOWINDENT	11	/* indent function entry/return */
936 #define	DTRACEOPT_QUIET		12	/* only output explicitly traced data */
937 #define	DTRACEOPT_STACKFRAMES	13	/* number of stack frames */
938 #define	DTRACEOPT_USTACKFRAMES	14	/* number of user stack frames */
939 #define	DTRACEOPT_AGGRATE	15	/* aggregation snapshot rate */
940 #define	DTRACEOPT_SWITCHRATE	16	/* buffer switching rate */
941 #define	DTRACEOPT_STATUSRATE	17	/* status rate */
942 #define	DTRACEOPT_DESTRUCTIVE	18	/* destructive actions allowed */
943 #define	DTRACEOPT_STACKINDENT	19	/* output indent for stack traces */
944 #define	DTRACEOPT_RAWBYTES	20	/* always print bytes in raw form */
945 #define	DTRACEOPT_JSTACKFRAMES	21	/* number of jstack() frames */
946 #define	DTRACEOPT_JSTACKSTRSIZE	22	/* size of jstack() string table */
947 #define	DTRACEOPT_MAX		23	/* number of options */
948 
949 #define	DTRACEOPT_UNSET		(dtrace_optval_t)-2	/* unset option */
950 
951 #define	DTRACEOPT_BUFPOLICY_RING	0	/* ring buffer */
952 #define	DTRACEOPT_BUFPOLICY_FILL	1	/* fill buffer, then stop */
953 #define	DTRACEOPT_BUFPOLICY_SWITCH	2	/* switch buffers */
954 
955 #define	DTRACEOPT_BUFRESIZE_AUTO	0	/* automatic resizing */
956 #define	DTRACEOPT_BUFRESIZE_MANUAL	1	/* manual resizing */
957 
958 /*
959  * DTrace Buffer Interface
960  *
961  * In order to get a snapshot of the principal or aggregation buffer,
962  * user-level passes a buffer description to the kernel with the dtrace_bufdesc
963  * structure.  This describes which CPU user-level is interested in, and
964  * where user-level wishes the kernel to snapshot the buffer to (the
965  * dtbd_data field).  The kernel uses the same structure to pass back some
966  * information regarding the buffer:  the size of data actually copied out, the
967  * number of drops, the number of errors, and the offset of the oldest record.
968  * If the buffer policy is a "switch" policy, taking a snapshot of the
969  * principal buffer has the additional effect of switching the active and
970  * inactive buffers.  Taking a snapshot of the aggregation buffer _always_ has
971  * the additional effect of switching the active and inactive buffers.
972  */
973 typedef struct dtrace_bufdesc {
974 	uint64_t dtbd_size;			/* size of buffer */
975 	uint32_t dtbd_cpu;			/* CPU or DTRACE_CPUALL */
976 	uint32_t dtbd_errors;			/* number of errors */
977 	uint64_t dtbd_drops;			/* number of drops */
978 	DTRACE_PTR(char, dtbd_data);		/* data */
979 	uint64_t dtbd_oldest;			/* offset of oldest record */
980 } dtrace_bufdesc_t;
981 
982 /*
983  * DTrace Status
984  *
985  * The status of DTrace is relayed via the dtrace_status structure.  This
986  * structure contains members to count drops other than the capacity drops
987  * available via the buffer interface (see above).  This consists of dynamic
988  * drops (including capacity dynamic drops, rinsing drops and dirty drops), and
989  * speculative drops (including capacity speculative drops, drops due to busy
990  * speculative buffers and drops due to unavailable speculative buffers).
991  * Additionally, the status structure contains a field to indicate the number
992  * of "fill"-policy buffers have been filled and a boolean field to indicate
993  * that exit() has been called.  If the dtst_exiting field is non-zero, no
994  * further data will be generated until tracing is stopped (at which time any
995  * enablings of the END action will be processed); if user-level sees that
996  * this field is non-zero, tracing should be stopped as soon as possible.
997  */
998 typedef struct dtrace_status {
999 	uint64_t dtst_dyndrops;			/* dynamic drops */
1000 	uint64_t dtst_dyndrops_rinsing;		/* dyn drops due to rinsing */
1001 	uint64_t dtst_dyndrops_dirty;		/* dyn drops due to dirty */
1002 	uint64_t dtst_specdrops;		/* speculative drops */
1003 	uint64_t dtst_specdrops_busy;		/* spec drops due to busy */
1004 	uint64_t dtst_specdrops_unavail;	/* spec drops due to unavail */
1005 	uint64_t dtst_errors;			/* total errors */
1006 	uint64_t dtst_filled;			/* number of filled bufs */
1007 	uint64_t dtst_stkstroverflows;		/* stack string tab overflows */
1008 	uint64_t dtst_dblerrors;		/* errors in ERROR probes */
1009 	char dtst_killed;			/* non-zero if killed */
1010 	char dtst_exiting;			/* non-zero if exit() called */
1011 	char dtst_pad[6];			/* pad out to 64-bit align */
1012 } dtrace_status_t;
1013 
1014 /*
1015  * DTrace Configuration
1016  *
1017  * User-level may need to understand some elements of the kernel DTrace
1018  * configuration in order to generate correct DIF.  This information is
1019  * conveyed via the dtrace_conf structure.
1020  */
1021 typedef struct dtrace_conf {
1022 	uint_t dtc_difversion;			/* supported DIF version */
1023 	uint_t dtc_difintregs;			/* # of DIF integer registers */
1024 	uint_t dtc_diftupregs;			/* # of DIF tuple registers */
1025 	uint_t dtc_ctfmodel;			/* CTF data model */
1026 	uint_t dtc_pad[8];			/* reserved for future use */
1027 } dtrace_conf_t;
1028 
1029 /*
1030  * DTrace Faults
1031  *
1032  * The constants below DTRACEFLT_LIBRARY indicate probe processing faults;
1033  * constants at or above DTRACEFLT_LIBRARY indicate faults in probe
1034  * postprocessing at user-level.  Probe processing faults induce an ERROR
1035  * probe and are replicated in unistd.d to allow users' ERROR probes to decode
1036  * the error condition using thse symbolic labels.
1037  */
1038 #define	DTRACEFLT_UNKNOWN		0	/* Unknown fault */
1039 #define	DTRACEFLT_BADADDR		1	/* Bad address */
1040 #define	DTRACEFLT_BADALIGN		2	/* Bad alignment */
1041 #define	DTRACEFLT_ILLOP			3	/* Illegal operation */
1042 #define	DTRACEFLT_DIVZERO		4	/* Divide-by-zero */
1043 #define	DTRACEFLT_NOSCRATCH		5	/* Out of scratch space */
1044 #define	DTRACEFLT_KPRIV			6	/* Illegal kernel access */
1045 #define	DTRACEFLT_UPRIV			7	/* Illegal user access */
1046 #define	DTRACEFLT_TUPOFLOW		8	/* Tuple stack overflow */
1047 
1048 #define	DTRACEFLT_LIBRARY		1000	/* Library-level fault */
1049 
1050 /*
1051  * DTrace Argument Types
1052  *
1053  * Because it would waste both space and time, argument types do not reside
1054  * with the probe.  In order to determine argument types for args[X]
1055  * variables, the D compiler queries for argument types on a probe-by-probe
1056  * basis.  (This optimizes for the common case that arguments are either not
1057  * used or used in an untyped fashion.)  Typed arguments are specified with a
1058  * string of the type name in the dtragd_native member of the argument
1059  * description structure.  Typed arguments may be further translated to types
1060  * of greater stability; the provider indicates such a translated argument by
1061  * filling in the dtargd_xlate member with the string of the translated type.
1062  * Finally, the provider may indicate which argument value a given argument
1063  * maps to by setting the dtargd_mapping member -- allowing a single argument
1064  * to map to multiple args[X] variables.
1065  */
1066 typedef struct dtrace_argdesc {
1067 	dtrace_id_t dtargd_id;			/* probe identifier */
1068 	int dtargd_ndx;				/* arg number (-1 iff none) */
1069 	int dtargd_mapping;			/* value mapping */
1070 	char dtargd_native[DTRACE_ARGTYPELEN];	/* native type name */
1071 	char dtargd_xlate[DTRACE_ARGTYPELEN];	/* translated type name */
1072 } dtrace_argdesc_t;
1073 
1074 /*
1075  * DTrace Stability Attributes
1076  *
1077  * Each DTrace provider advertises the name and data stability of each of its
1078  * probe description components, as well as its architectural dependencies.
1079  * The D compiler can query the provider attributes (dtrace_pattr_t below) in
1080  * order to compute the properties of an input program and report them.
1081  */
1082 typedef uint8_t dtrace_stability_t;	/* stability code (see attributes(5)) */
1083 typedef uint8_t dtrace_class_t;		/* architectural dependency class */
1084 
1085 #define	DTRACE_STABILITY_INTERNAL	0	/* private to DTrace itself */
1086 #define	DTRACE_STABILITY_PRIVATE	1	/* private to Sun (see docs) */
1087 #define	DTRACE_STABILITY_OBSOLETE	2	/* scheduled for removal */
1088 #define	DTRACE_STABILITY_EXTERNAL	3	/* not controlled by Sun */
1089 #define	DTRACE_STABILITY_UNSTABLE	4	/* new or rapidly changing */
1090 #define	DTRACE_STABILITY_EVOLVING	5	/* less rapidly changing */
1091 #define	DTRACE_STABILITY_STABLE		6	/* mature interface from Sun */
1092 #define	DTRACE_STABILITY_STANDARD	7	/* industry standard */
1093 #define	DTRACE_STABILITY_MAX		7	/* maximum valid stability */
1094 
1095 #define	DTRACE_CLASS_UNKNOWN	0	/* unknown architectural dependency */
1096 #define	DTRACE_CLASS_CPU	1	/* CPU-module-specific */
1097 #define	DTRACE_CLASS_PLATFORM	2	/* platform-specific (uname -i) */
1098 #define	DTRACE_CLASS_GROUP	3	/* hardware-group-specific (uname -m) */
1099 #define	DTRACE_CLASS_ISA	4	/* ISA-specific (uname -p) */
1100 #define	DTRACE_CLASS_COMMON	5	/* common to all systems */
1101 #define	DTRACE_CLASS_MAX	5	/* maximum valid class */
1102 
1103 #define	DTRACE_PRIV_NONE	0x0000
1104 #define	DTRACE_PRIV_KERNEL	0x0001
1105 #define	DTRACE_PRIV_USER	0x0002
1106 #define	DTRACE_PRIV_PROC	0x0004
1107 #define	DTRACE_PRIV_OWNER	0x0008
1108 
1109 #define	DTRACE_PRIV_ALL	\
1110 	(DTRACE_PRIV_KERNEL | DTRACE_PRIV_USER | \
1111 	DTRACE_PRIV_PROC | DTRACE_PRIV_OWNER)
1112 
1113 typedef struct dtrace_ppriv {
1114 	uint32_t dtpp_flags;			/* privilege flags */
1115 	uid_t dtpp_uid;				/* user ID */
1116 } dtrace_ppriv_t;
1117 
1118 typedef struct dtrace_attribute {
1119 	dtrace_stability_t dtat_name;		/* entity name stability */
1120 	dtrace_stability_t dtat_data;		/* entity data stability */
1121 	dtrace_class_t dtat_class;		/* entity data dependency */
1122 } dtrace_attribute_t;
1123 
1124 typedef struct dtrace_pattr {
1125 	dtrace_attribute_t dtpa_provider;	/* provider attributes */
1126 	dtrace_attribute_t dtpa_mod;		/* module attributes */
1127 	dtrace_attribute_t dtpa_func;		/* function attributes */
1128 	dtrace_attribute_t dtpa_name;		/* name attributes */
1129 	dtrace_attribute_t dtpa_args;		/* args[] attributes */
1130 } dtrace_pattr_t;
1131 
1132 typedef struct dtrace_providerdesc {
1133 	char dtvd_name[DTRACE_PROVNAMELEN];	/* provider name */
1134 	dtrace_pattr_t dtvd_attr;		/* stability attributes */
1135 	dtrace_ppriv_t dtvd_priv;		/* privileges required */
1136 } dtrace_providerdesc_t;
1137 
1138 /*
1139  * DTrace Pseudodevice Interface
1140  *
1141  * DTrace is controlled through ioctl(2)'s to the in-kernel dtrace:dtrace
1142  * pseudodevice driver.  These ioctls comprise the user-kernel interface to
1143  * DTrace.
1144  */
1145 #define	DTRACEIOC		(('d' << 24) | ('t' << 16) | ('r' << 8))
1146 #define	DTRACEIOC_PROVIDER	(DTRACEIOC | 1)		/* provider query */
1147 #define	DTRACEIOC_PROBES	(DTRACEIOC | 2)		/* probe query */
1148 #define	DTRACEIOC_BUFSNAP	(DTRACEIOC | 4)		/* snapshot buffer */
1149 #define	DTRACEIOC_PROBEMATCH	(DTRACEIOC | 5)		/* match probes */
1150 #define	DTRACEIOC_ENABLE	(DTRACEIOC | 6)		/* enable probes */
1151 #define	DTRACEIOC_AGGSNAP	(DTRACEIOC | 7)		/* snapshot agg. */
1152 #define	DTRACEIOC_EPROBE	(DTRACEIOC | 8)		/* get eprobe desc. */
1153 #define	DTRACEIOC_PROBEARG	(DTRACEIOC | 9)		/* get probe arg */
1154 #define	DTRACEIOC_CONF		(DTRACEIOC | 10)	/* get config. */
1155 #define	DTRACEIOC_STATUS	(DTRACEIOC | 11)	/* get status */
1156 #define	DTRACEIOC_GO		(DTRACEIOC | 12)	/* start tracing */
1157 #define	DTRACEIOC_STOP		(DTRACEIOC | 13)	/* stop tracing */
1158 #define	DTRACEIOC_AGGDESC	(DTRACEIOC | 15)	/* get agg. desc. */
1159 #define	DTRACEIOC_FORMAT	(DTRACEIOC | 16)	/* get format str */
1160 #define	DTRACEIOC_DOFGET	(DTRACEIOC | 17)	/* get DOF */
1161 #define	DTRACEIOC_REPLICATE	(DTRACEIOC | 18)	/* replicate enab */
1162 
1163 /*
1164  * DTrace Helpers
1165  *
1166  * In general, DTrace establishes probes in processes and takes actions on
1167  * processes without knowing their specific user-level structures.  Instead of
1168  * existing in the framework, process-specific knowledge is contained by the
1169  * enabling D program -- which can apply process-specific knowledge by making
1170  * appropriate use of DTrace primitives like copyin() and copyinstr() to
1171  * operate on user-level data.  However, there may exist some specific probes
1172  * of particular semantic relevance that the application developer may wish to
1173  * explicitly export.  For example, an application may wish to export a probe
1174  * at the point that it begins and ends certain well-defined transactions.  In
1175  * addition to providing probes, programs may wish to offer assistance for
1176  * certain actions.  For example, in highly dynamic environments (e.g., Java),
1177  * it may be difficult to obtain a stack trace in terms of meaningful symbol
1178  * names (the translation from instruction addresses to corresponding symbol
1179  * names may only be possible in situ); these environments may wish to define
1180  * a series of actions to be applied in situ to obtain a meaningful stack
1181  * trace.
1182  *
1183  * These two mechanisms -- user-level statically defined tracing and assisting
1184  * DTrace actions -- are provided via DTrace _helpers_.  Helpers are specified
1185  * via DOF, but unlike enabling DOF, helper DOF may contain definitions of
1186  * providers, probes and their arguments.  If a helper wishes to provide
1187  * action assistance, probe descriptions and corresponding DIF actions may be
1188  * specified in the helper DOF.  For such helper actions, however, the probe
1189  * description describes the specific helper:  all DTrace helpers have the
1190  * provider name "dtrace" and the module name "helper", and the name of the
1191  * helper is contained in the function name (for example, the ustack() helper
1192  * is named "ustack").  Any helper-specific name may be contained in the name
1193  * (for example, if a helper were to have a constructor, it might be named
1194  * "dtrace:helper:<helper>:init").  Helper actions are only called when the
1195  * action that they are helping is taken.  Helper actions may only return DIF
1196  * expressions, and may only call the following subroutines:
1197  *
1198  *    alloca()      <= Allocates memory out of the consumer's scratch space
1199  *    bcopy()       <= Copies memory to scratch space
1200  *    copyin()      <= Copies memory from user-level into consumer's scratch
1201  *    copyinto()    <= Copies memory into a specific location in scratch
1202  *    copyinstr()   <= Copies a string into a specific location in scratch
1203  *
1204  * Helper actions may only access the following built-in variables:
1205  *
1206  *    curthread     <= Current kthread_t pointer
1207  *    tid           <= Current thread identifier
1208  *    pid           <= Current process identifier
1209  *    execname      <= Current executable name
1210  *
1211  * Helper actions may not manipulate or allocate dynamic variables, but they
1212  * may have clause-local and statically-allocated global variables.  The
1213  * helper action variable state is specific to the helper action -- variables
1214  * used by the helper action may not be accessed outside of the helper
1215  * action, and the helper action may not access variables that like outside
1216  * of it.  Helper actions may not load from kernel memory at-large; they are
1217  * restricting to loading current user state (via copyin() and variants) and
1218  * scratch space.  As with probe enablings, helper actions are executed in
1219  * program order.  The result of the helper action is the result of the last
1220  * executing helper expression.
1221  *
1222  * Helpers -- composed of either providers/probes or probes/actions (or both)
1223  * -- are added by opening the "helper" minor node, and issuing an ioctl(2)
1224  * (DTRACEHIOC_ADDDOF) that specifies the dof_helper_t structure. This
1225  * encapsulates the name and base address of the user-level library or
1226  * executable publishing the helpers and probes as well as the DOF that
1227  * contains the definitions of those helpers and probes.
1228  *
1229  * The DTRACEHIOC_ADD and DTRACEHIOC_REMOVE are left in place for legacy
1230  * helpers and should no longer be used.  No other ioctls are valid on the
1231  * helper minor node.
1232  */
1233 #define	DTRACEHIOC		(('d' << 24) | ('t' << 16) | ('h' << 8))
1234 #define	DTRACEHIOC_ADD		(DTRACEHIOC | 1)	/* add helper */
1235 #define	DTRACEHIOC_REMOVE	(DTRACEHIOC | 2)	/* remove helper */
1236 #define	DTRACEHIOC_ADDDOF	(DTRACEHIOC | 3)	/* add helper DOF */
1237 
1238 typedef struct dof_helper {
1239 	char dofhp_mod[DTRACE_MODNAMELEN];	/* executable or library name */
1240 	uint64_t dofhp_addr;			/* base address of object */
1241 	uint64_t dofhp_dof;			/* address of helper DOF */
1242 } dof_helper_t;
1243 
1244 #define	DTRACEMNR_DTRACE	"dtrace"	/* node for DTrace ops */
1245 #define	DTRACEMNR_HELPER	"helper"	/* node for helpers */
1246 #define	DTRACEMNRN_DTRACE	0		/* minor for DTrace ops */
1247 #define	DTRACEMNRN_HELPER	1		/* minor for helpers */
1248 #define	DTRACEMNRN_CLONE	2		/* first clone minor */
1249 
1250 #ifdef _KERNEL
1251 
1252 /*
1253  * DTrace Provider API
1254  *
1255  * The following functions are implemented by the DTrace framework and are
1256  * used to implement separate in-kernel DTrace providers.  Common functions
1257  * are provided in uts/common/os/dtrace.c.  ISA-dependent subroutines are
1258  * defined in uts/<isa>/dtrace/dtrace_asm.s or uts/<isa>/dtrace/dtrace_isa.c.
1259  *
1260  * The provider API has two halves:  the API that the providers consume from
1261  * DTrace, and the API that providers make available to DTrace.
1262  *
1263  * 1 Framework-to-Provider API
1264  *
1265  * 1.1  Overview
1266  *
1267  * The Framework-to-Provider API is represented by the dtrace_pops structure
1268  * that the provider passes to the framework when registering itself.  This
1269  * structure consists of the following members:
1270  *
1271  *   dtps_provide()          <-- Provide all probes, all modules
1272  *   dtps_provide_module()   <-- Provide all probes in specified module
1273  *   dtps_enable()           <-- Enable specified probe
1274  *   dtps_disable()          <-- Disable specified probe
1275  *   dtps_suspend()          <-- Suspend specified probe
1276  *   dtps_resume()           <-- Resume specified probe
1277  *   dtps_getargdesc()       <-- Get the argument description for args[X]
1278  *   dtps_getargval()        <-- Get the value for an argX or args[X] variable
1279  *   dtps_usermode()         <-- Find out if the probe was fired in user mode
1280  *   dtps_destroy()          <-- Destroy all state associated with this probe
1281  *
1282  * 1.2  void dtps_provide(void *arg, const dtrace_probedesc_t *spec)
1283  *
1284  * 1.2.1  Overview
1285  *
1286  *   Called to indicate that the provider should provide all probes.  If the
1287  *   specified description is non-NULL, dtps_provide() is being called because
1288  *   no probe matched a specified probe -- if the provider has the ability to
1289  *   create custom probes, it may wish to create a probe that matches the
1290  *   specified description.
1291  *
1292  * 1.2.2  Arguments and notes
1293  *
1294  *   The first argument is the cookie as passed to dtrace_register().  The
1295  *   second argument is a pointer to a probe description that the provider may
1296  *   wish to consider when creating custom probes.  The provider is expected to
1297  *   call back into the DTrace framework via dtrace_probe_create() to create
1298  *   any necessary probes.  dtps_provide() may be called even if the provider
1299  *   has made available all probes; the provider should check the return value
1300  *   of dtrace_probe_create() to handle this case.  Note that the provider need
1301  *   not implement both dtps_provide() and dtps_provide_module(); see
1302  *   "Arguments and Notes" for dtrace_register(), below.
1303  *
1304  * 1.2.3  Return value
1305  *
1306  *   None.
1307  *
1308  * 1.2.4  Caller's context
1309  *
1310  *   dtps_provide() is typically called from open() or ioctl() context, but may
1311  *   be called from other contexts as well.  The DTrace framework is locked in
1312  *   such a way that providers may not register or unregister.  This means that
1313  *   the provider may not call any DTrace API that affects its registration with
1314  *   the framework, including dtrace_register(), dtrace_unregister(),
1315  *   dtrace_invalidate(), and dtrace_condense().  However, the context is such
1316  *   that the provider may (and indeed, is expected to) call probe-related
1317  *   DTrace routines, including dtrace_probe_create(), dtrace_probe_lookup(),
1318  *   and dtrace_probe_arg().
1319  *
1320  * 1.3  void dtps_provide_module(void *arg, struct modctl *mp)
1321  *
1322  * 1.3.1  Overview
1323  *
1324  *   Called to indicate that the provider should provide all probes in the
1325  *   specified module.
1326  *
1327  * 1.3.2  Arguments and notes
1328  *
1329  *   The first argument is the cookie as passed to dtrace_register().  The
1330  *   second argument is a pointer to a modctl structure that indicates the
1331  *   module for which probes should be created.
1332  *
1333  * 1.3.3  Return value
1334  *
1335  *   None.
1336  *
1337  * 1.3.4  Caller's context
1338  *
1339  *   dtps_provide_module() may be called from open() or ioctl() context, but
1340  *   may also be called from a module loading context.  mod_lock is held, and
1341  *   the DTrace framework is locked in such a way that providers may not
1342  *   register or unregister.  This means that the provider may not call any
1343  *   DTrace API that affects its registration with the framework, including
1344  *   dtrace_register(), dtrace_unregister(), dtrace_invalidate(), and
1345  *   dtrace_condense().  However, the context is such that the provider may (and
1346  *   indeed, is expected to) call probe-related DTrace routines, including
1347  *   dtrace_probe_create(), dtrace_probe_lookup(), and dtrace_probe_arg().  Note
1348  *   that the provider need not implement both dtps_provide() and
1349  *   dtps_provide_module(); see "Arguments and Notes" for dtrace_register(),
1350  *   below.
1351  *
1352  * 1.4  void dtps_enable(void *arg, dtrace_id_t id, void *parg)
1353  *
1354  * 1.4.1  Overview
1355  *
1356  *   Called to enable the specified probe.
1357  *
1358  * 1.4.2  Arguments and notes
1359  *
1360  *   The first argument is the cookie as passed to dtrace_register().  The
1361  *   second argument is the identifier of the probe to be enabled.  The third
1362  *   argument is the probe argument as passed to dtrace_probe_create().
1363  *   dtps_enable() will be called when a probe transitions from not being
1364  *   enabled at all to having one or more ECB.  The number of ECBs associated
1365  *   with the probe may change without subsequent calls into the provider.
1366  *   When the number of ECBs drops to zero, the provider will be explicitly
1367  *   told to disable the probe via dtps_disable().  dtrace_probe() should never
1368  *   be called for a probe identifier that hasn't been explicitly enabled via
1369  *   dtps_enable().
1370  *
1371  * 1.4.3  Return value
1372  *
1373  *   None.
1374  *
1375  * 1.4.4  Caller's context
1376  *
1377  *   The DTrace framework is locked in such a way that it may not be called
1378  *   back into at all.  cpu_lock is held.  mod_lock is not held and may not
1379  *   be acquired.
1380  *
1381  * 1.5  void dtps_disable(void *arg, dtrace_id_t id, void *parg)
1382  *
1383  * 1.5.1  Overview
1384  *
1385  *   Called to disable the specified probe.
1386  *
1387  * 1.5.2  Arguments and notes
1388  *
1389  *   The first argument is the cookie as passed to dtrace_register().  The
1390  *   second argument is the identifier of the probe to be disabled.  The third
1391  *   argument is the probe argument as passed to dtrace_probe_create().
1392  *   dtps_disable() will be called when a probe transitions from being enabled
1393  *   to having zero ECBs.  dtrace_probe() should never be called for a probe
1394  *   identifier that has been explicitly enabled via dtps_disable().
1395  *
1396  * 1.5.3  Return value
1397  *
1398  *   None.
1399  *
1400  * 1.5.4  Caller's context
1401  *
1402  *   The DTrace framework is locked in such a way that it may not be called
1403  *   back into at all.  cpu_lock is held.  mod_lock is not held and may not
1404  *   be acquired.
1405  *
1406  * 1.6  void dtps_suspend(void *arg, dtrace_id_t id, void *parg)
1407  *
1408  * 1.6.1  Overview
1409  *
1410  *   Called to suspend the specified enabled probe.  This entry point is for
1411  *   providers that may need to suspend some or all of their probes when CPUs
1412  *   are being powered on or when the boot monitor is being entered for a
1413  *   prolonged period of time.
1414  *
1415  * 1.6.2  Arguments and notes
1416  *
1417  *   The first argument is the cookie as passed to dtrace_register().  The
1418  *   second argument is the identifier of the probe to be suspended.  The
1419  *   third argument is the probe argument as passed to dtrace_probe_create().
1420  *   dtps_suspend will only be called on an enabled probe.  Providers that
1421  *   provide a dtps_suspend entry point will want to take roughly the action
1422  *   that it takes for dtps_disable.
1423  *
1424  * 1.6.3  Return value
1425  *
1426  *   None.
1427  *
1428  * 1.6.4  Caller's context
1429  *
1430  *   Interrupts are disabled.  The DTrace framework is in a state such that the
1431  *   specified probe cannot be disabled or destroyed for the duration of
1432  *   dtps_suspend().  As interrupts are disabled, the provider is afforded
1433  *   little latitude; the provider is expected to do no more than a store to
1434  *   memory.
1435  *
1436  * 1.7  void dtps_resume(void *arg, dtrace_id_t id, void *parg)
1437  *
1438  * 1.7.1  Overview
1439  *
1440  *   Called to resume the specified enabled probe.  This entry point is for
1441  *   providers that may need to resume some or all of their probes after the
1442  *   completion of an event that induced a call to dtps_suspend().
1443  *
1444  * 1.7.2  Arguments and notes
1445  *
1446  *   The first argument is the cookie as passed to dtrace_register().  The
1447  *   second argument is the identifier of the probe to be resumed.  The
1448  *   third argument is the probe argument as passed to dtrace_probe_create().
1449  *   dtps_resume will only be called on an enabled probe.  Providers that
1450  *   provide a dtps_resume entry point will want to take roughly the action
1451  *   that it takes for dtps_enable.
1452  *
1453  * 1.7.3  Return value
1454  *
1455  *   None.
1456  *
1457  * 1.7.4  Caller's context
1458  *
1459  *   Interrupts are disabled.  The DTrace framework is in a state such that the
1460  *   specified probe cannot be disabled or destroyed for the duration of
1461  *   dtps_resume().  As interrupts are disabled, the provider is afforded
1462  *   little latitude; the provider is expected to do no more than a store to
1463  *   memory.
1464  *
1465  * 1.8  void dtps_getargdesc(void *arg, dtrace_id_t id, void *parg,
1466  *           dtrace_argdesc_t *desc)
1467  *
1468  * 1.8.1  Overview
1469  *
1470  *   Called to retrieve the argument description for an args[X] variable.
1471  *
1472  * 1.8.2  Arguments and notes
1473  *
1474  *   The first argument is the cookie as passed to dtrace_register(). The
1475  *   second argument is the identifier of the current probe. The third
1476  *   argument is the probe argument as passed to dtrace_probe_create(). The
1477  *   fourth argument is a pointer to the argument description.  This
1478  *   description is both an input and output parameter:  it contains the
1479  *   index of the desired argument in the dtargd_ndx field, and expects
1480  *   the other fields to be filled in upon return.  If there is no argument
1481  *   corresponding to the specified index, the dtargd_ndx field should be set
1482  *   to DTRACE_ARGNONE.
1483  *
1484  * 1.8.3  Return value
1485  *
1486  *   None.  The dtargd_ndx, dtargd_native, dtargd_xlate and dtargd_mapping
1487  *   members of the dtrace_argdesc_t structure are all output values.
1488  *
1489  * 1.8.4  Caller's context
1490  *
1491  *   dtps_getargdesc() is called from ioctl() context. mod_lock is held, and
1492  *   the DTrace framework is locked in such a way that providers may not
1493  *   register or unregister.  This means that the provider may not call any
1494  *   DTrace API that affects its registration with the framework, including
1495  *   dtrace_register(), dtrace_unregister(), dtrace_invalidate(), and
1496  *   dtrace_condense().
1497  *
1498  * 1.9  uint64_t dtps_getargval(void *arg, dtrace_id_t id, void *parg,
1499  *               int argno, int aframes)
1500  *
1501  * 1.9.1  Overview
1502  *
1503  *   Called to retrieve a value for an argX or args[X] variable.
1504  *
1505  * 1.9.2  Arguments and notes
1506  *
1507  *   The first argument is the cookie as passed to dtrace_register(). The
1508  *   second argument is the identifier of the current probe. The third
1509  *   argument is the probe argument as passed to dtrace_probe_create(). The
1510  *   fourth argument is the number of the argument (the X in the example in
1511  *   1.9.1). The fifth argument is the number of stack frames that were used
1512  *   to get from the actual place in the code that fired the probe to
1513  *   dtrace_probe() itself, the so-called artificial frames. This argument may
1514  *   be used to descend an appropriate number of frames to find the correct
1515  *   values. If this entry point is left NULL, the dtrace_getarg() built-in
1516  *   function is used.
1517  *
1518  * 1.9.3  Return value
1519  *
1520  *   The value of the argument.
1521  *
1522  * 1.9.4  Caller's context
1523  *
1524  *   This is called from within dtrace_probe() meaning that interrupts
1525  *   are disabled. No locks should be taken within this entry point.
1526  *
1527  * 1.10  int dtps_usermode(void *arg, dtrace_id_t id, void *parg)
1528  *
1529  * 1.10.1  Overview
1530  *
1531  *   Called to determine if the probe was fired in a user context.
1532  *
1533  * 1.10.2  Arguments and notes
1534  *
1535  *   The first argument is the cookie as passed to dtrace_register(). The
1536  *   second argument is the identifier of the current probe. The third
1537  *   argument is the probe argument as passed to dtrace_probe_create().  This
1538  *   entry point must not be left NULL for providers whose probes allow for
1539  *   mixed mode tracing, that is to say those probes that can fire during
1540  *   kernel- _or_ user-mode execution
1541  *
1542  * 1.10.3  Return value
1543  *
1544  *   A boolean value.
1545  *
1546  * 1.10.4  Caller's context
1547  *
1548  *   This is called from within dtrace_probe() meaning that interrupts
1549  *   are disabled. No locks should be taken within this entry point.
1550  *
1551  * 1.11 void dtps_destroy(void *arg, dtrace_id_t id, void *parg)
1552  *
1553  * 1.11.1 Overview
1554  *
1555  *   Called to destroy the specified probe.
1556  *
1557  * 1.11.2 Arguments and notes
1558  *
1559  *   The first argument is the cookie as passed to dtrace_register().  The
1560  *   second argument is the identifier of the probe to be destroyed.  The third
1561  *   argument is the probe argument as passed to dtrace_probe_create().  The
1562  *   provider should free all state associated with the probe.  The framework
1563  *   guarantees that dtps_destroy() is only called for probes that have either
1564  *   been disabled via dtps_disable() or were never enabled via dtps_enable().
1565  *   Once dtps_disable() has been called for a probe, no further call will be
1566  *   made specifying the probe.
1567  *
1568  * 1.11.3 Return value
1569  *
1570  *   None.
1571  *
1572  * 1.11.4 Caller's context
1573  *
1574  *   The DTrace framework is locked in such a way that it may not be called
1575  *   back into at all.  mod_lock is held.  cpu_lock is not held, and may not be
1576  *   acquired.
1577  *
1578  *
1579  * 2 Provider-to-Framework API
1580  *
1581  * 2.1  Overview
1582  *
1583  * The Provider-to-Framework API provides the mechanism for the provider to
1584  * register itself with the DTrace framework, to create probes, to lookup
1585  * probes and (most importantly) to fire probes.  The Provider-to-Framework
1586  * consists of:
1587  *
1588  *   dtrace_register()       <-- Register a provider with the DTrace framework
1589  *   dtrace_unregister()     <-- Remove a provider's DTrace registration
1590  *   dtrace_invalidate()     <-- Invalidate the specified provider
1591  *   dtrace_condense()       <-- Remove a provider's unenabled probes
1592  *   dtrace_attached()       <-- Indicates whether or not DTrace has attached
1593  *   dtrace_probe_create()   <-- Create a DTrace probe
1594  *   dtrace_probe_lookup()   <-- Lookup a DTrace probe based on its name
1595  *   dtrace_probe_arg()      <-- Return the probe argument for a specific probe
1596  *   dtrace_probe()          <-- Fire the specified probe
1597  *
1598  * 2.2  int dtrace_register(const char *name, const dtrace_pattr_t *pap,
1599  *          uint32_t priv, uid_t uid, const dtrace_pops_t *pops, void *arg,
1600  *          dtrace_provider_id_t *idp)
1601  *
1602  * 2.2.1  Overview
1603  *
1604  *   dtrace_register() registers the calling provider with the DTrace
1605  *   framework.  It should generally be called by DTrace providers in their
1606  *   attach(9E) entry point.
1607  *
1608  * 2.2.2  Arguments and Notes
1609  *
1610  *   The first argument is the name of the provider.  The second argument is a
1611  *   pointer to the stability attributes for the provider.  The third argument
1612  *   is the privilege flags for the provider, and must be some combination of:
1613  *
1614  *     DTRACE_PRIV_NONE     <= All users may enable probes from this provider
1615  *
1616  *     DTRACE_PRIV_PROC     <= Any user with privilege of PRIV_DTRACE_PROC may
1617  *                             enable probes from this provider
1618  *
1619  *     DTRACE_PRIV_USER     <= Any user with privilege of PRIV_DTRACE_USER may
1620  *                             enable probes from this provider
1621  *
1622  *     DTRACE_PRIV_KERNEL   <= Any user with privilege of PRIV_DTRACE_KERNEL
1623  *                             may enable probes from this provider
1624  *
1625  *     DTRACE_PRIV_OWNER    <= This flag places an additional constraint on
1626  *                             the privilege requirements above. These probes
1627  *                             require either (a) a user ID matching the user
1628  *                             ID passed as the fourth argument to
1629  *                             dtrace_register() or (b) the PRIV_PROC_OWNER
1630  *                             privilege.
1631  *
1632  *   Note that these flags designate the _visibility_ of the probes, not
1633  *   the conditions under which they may or may not fire.
1634  *
1635  *   The fourth argument is a user ID that is associated with the provider.
1636  *   This argument should be 0 if the privilege flags don't include
1637  *   DTRACE_PRIV_OWNER.
1638  *
1639  *   The fifth argument is a DTrace provider operations vector, which provides
1640  *   the implementation for the Framework-to-Provider API.  (See Section 1,
1641  *   above.)  This must be non-NULL, and each member must be non-NULL.  The
1642  *   exceptions to this are (1) the dtps_provide() and dtps_provide_module()
1643  *   members (if the provider so desires, _one_ of these members may be left
1644  *   NULL -- denoting that the provider only implements the other) and (2)
1645  *   the dtps_suspend() and dtps_resume() members, which must either both be
1646  *   NULL or both be non-NULL.
1647  *
1648  *   The sixth argument is a cookie to be specified as the first argument for
1649  *   each function in the Framework-to-Provider API.  This argument may have
1650  *   any value.
1651  *
1652  *   The final argument is a pointer to dtrace_provider_id_t.  If
1653  *   dtrace_register() successfully completes, the provider identifier will be
1654  *   stored in the memory pointed to be this argument.  This argument must be
1655  *   non-NULL.
1656  *
1657  * 2.2.3  Return value
1658  *
1659  *   On success, dtrace_register() returns 0 and stores the new provider's
1660  *   identifier into the memory pointed to by the idp argument.  On failure,
1661  *   dtrace_register() returns an errno:
1662  *
1663  *     EINVAL   The arguments passed to dtrace_register() were somehow invalid.
1664  *              This may because a parameter that must be non-NULL was NULL,
1665  *              because the name was invalid (either empty or an illegal
1666  *              provider name) or because the attributes were invalid.
1667  *
1668  *   No other failure code is returned.
1669  *
1670  * 2.2.4  Caller's context
1671  *
1672  *   dtrace_register() may induce calls to dtrace_provide(); the provider must
1673  *   hold no locks across dtrace_register() that may also be acquired by
1674  *   dtrace_provide().  cpu_lock and mod_lock must not be held.
1675  *
1676  * 2.3  int dtrace_unregister(dtrace_provider_t id)
1677  *
1678  * 2.3.1  Overview
1679  *
1680  *   Unregisters the specified provider from the DTrace framework.  It should
1681  *   generally be called by DTrace providers in their detach(9E) entry point.
1682  *
1683  * 2.3.2  Arguments and Notes
1684  *
1685  *   The only argument is the provider identifier, as returned from a
1686  *   successful call to dtrace_register().  As a result of calling
1687  *   dtrace_unregister(), the DTrace framework will call back into the provider
1688  *   via the dtps_destroy() entry point.  Once dtrace_unregister() successfully
1689  *   completes, however, the DTrace framework will no longer make calls through
1690  *   the Framework-to-Provider API.
1691  *
1692  * 2.3.3  Return value
1693  *
1694  *   On success, dtrace_unregister returns 0.  On failure, dtrace_unregister()
1695  *   returns an errno:
1696  *
1697  *     EBUSY    There are currently processes that have the DTrace pseudodevice
1698  *              open, or there exists an anonymous enabling that hasn't yet
1699  *              been claimed.
1700  *
1701  *   No other failure code is returned.
1702  *
1703  * 2.3.4  Caller's context
1704  *
1705  *   Because a call to dtrace_unregister() may induce calls through the
1706  *   Framework-to-Provider API, the caller may not hold any lock across
1707  *   dtrace_register() that is also acquired in any of the Framework-to-
1708  *   Provider API functions.  Additionally, mod_lock may not be held.
1709  *
1710  * 2.4  void dtrace_invalidate(dtrace_provider_id_t id)
1711  *
1712  * 2.4.1  Overview
1713  *
1714  *   Invalidates the specified provider.  All subsequent probe lookups for the
1715  *   specified provider will fail, but its probes will not be removed.
1716  *
1717  * 2.4.2  Arguments and note
1718  *
1719  *   The only argument is the provider identifier, as returned from a
1720  *   successful call to dtrace_register().  In general, a provider's probes
1721  *   always remain valid; dtrace_invalidate() is a mechanism for invalidating
1722  *   an entire provider, regardless of whether or not probes are enabled or
1723  *   not.  Note that dtrace_invalidate() will _not_ prevent already enabled
1724  *   probes from firing -- it will merely prevent any new enablings of the
1725  *   provider's probes.
1726  *
1727  * 2.5 int dtrace_condense(dtrace_provider_id_t id)
1728  *
1729  * 2.5.1  Overview
1730  *
1731  *   Removes all the unenabled probes for the given provider. This function is
1732  *   not unlike dtrace_unregister(), except that it doesn't remove the
1733  *   provider just as many of its associated probes as it can.
1734  *
1735  * 2.5.2  Arguments and Notes
1736  *
1737  *   As with dtrace_unregister(), the sole argument is the provider identifier
1738  *   as returned from a successful call to dtrace_register().  As a result of
1739  *   calling dtrace_condense(), the DTrace framework will call back into the
1740  *   given provider's dtps_destroy() entry point for each of the provider's
1741  *   unenabled probes.
1742  *
1743  * 2.5.3  Return value
1744  *
1745  *   Currently, dtrace_condense() always returns 0.  However, consumers of this
1746  *   function should check the return value as appropriate; its behavior may
1747  *   change in the future.
1748  *
1749  * 2.5.4  Caller's context
1750  *
1751  *   As with dtrace_unregister(), the caller may not hold any lock across
1752  *   dtrace_condense() that is also acquired in the provider's entry points.
1753  *   Also, mod_lock may not be held.
1754  *
1755  * 2.6 int dtrace_attached()
1756  *
1757  * 2.6.1  Overview
1758  *
1759  *   Indicates whether or not DTrace has attached.
1760  *
1761  * 2.6.2  Arguments and Notes
1762  *
1763  *   For most providers, DTrace makes initial contact beyond registration.
1764  *   That is, once a provider has registered with DTrace, it waits to hear
1765  *   from DTrace to create probes.  However, some providers may wish to
1766  *   proactively create probes without first being told by DTrace to do so.
1767  *   If providers wish to do this, they must first call dtrace_attached() to
1768  *   determine if DTrace itself has attached.  If dtrace_attached() returns 0,
1769  *   the provider must not make any other Provider-to-Framework API call.
1770  *
1771  * 2.6.3  Return value
1772  *
1773  *   dtrace_attached() returns 1 if DTrace has attached, 0 otherwise.
1774  *
1775  * 2.7  int dtrace_probe_create(dtrace_provider_t id, const char *mod,
1776  *	    const char *func, const char *name, int aframes, void *arg)
1777  *
1778  * 2.7.1  Overview
1779  *
1780  *   Creates a probe with specified module name, function name, and name.
1781  *
1782  * 2.7.2  Arguments and Notes
1783  *
1784  *   The first argument is the provider identifier, as returned from a
1785  *   successful call to dtrace_register().  The second, third, and fourth
1786  *   arguments are the module name, function name, and probe name,
1787  *   respectively.  Of these, module name and function name may both be NULL
1788  *   (in which case the probe is considered to be unanchored), or they may both
1789  *   be non-NULL.  The name must be non-NULL, and must point to a non-empty
1790  *   string.
1791  *
1792  *   The fifth argument is the number of artificial stack frames that will be
1793  *   found on the stack when dtrace_probe() is called for the new probe.  These
1794  *   artificial frames will be automatically be pruned should the stack() or
1795  *   stackdepth() functions be called as part of one of the probe's ECBs.  If
1796  *   the parameter doesn't add an artificial frame, this parameter should be
1797  *   zero.
1798  *
1799  *   The final argument is a probe argument that will be passed back to the
1800  *   provider when a probe-specific operation is called.  (e.g., via
1801  *   dtps_enable(), dtps_disable(), etc.)
1802  *
1803  *   Note that it is up to the provider to be sure that the probe that it
1804  *   creates does not already exist -- if the provider is unsure of the probe's
1805  *   existence, it should assure its absence with dtrace_probe_lookup() before
1806  *   calling dtrace_probe_create().
1807  *
1808  * 2.7.3  Return value
1809  *
1810  *   dtrace_probe_create() always succeeds, and always returns the identifier
1811  *   of the newly-created probe.
1812  *
1813  * 2.7.4  Caller's context
1814  *
1815  *   While dtrace_probe_create() is generally expected to be called from
1816  *   dtps_provide() and/or dtps_provide_module(), it may be called from other
1817  *   non-DTrace contexts.  Neither cpu_lock nor mod_lock may be held.
1818  *
1819  * 2.8  dtrace_id_t dtrace_probe_lookup(dtrace_provider_t id, const char *mod,
1820  *	    const char *func, const char *name)
1821  *
1822  * 2.8.1  Overview
1823  *
1824  *   Looks up a probe based on provdider and one or more of module name,
1825  *   function name and probe name.
1826  *
1827  * 2.8.2  Arguments and Notes
1828  *
1829  *   The first argument is the provider identifier, as returned from a
1830  *   successful call to dtrace_register().  The second, third, and fourth
1831  *   arguments are the module name, function name, and probe name,
1832  *   respectively.  Any of these may be NULL; dtrace_probe_lookup() will return
1833  *   the identifier of the first probe that is provided by the specified
1834  *   provider and matches all of the non-NULL matching criteria.
1835  *   dtrace_probe_lookup() is generally used by a provider to be check the
1836  *   existence of a probe before creating it with dtrace_probe_create().
1837  *
1838  * 2.8.3  Return value
1839  *
1840  *   If the probe exists, returns its identifier.  If the probe does not exist,
1841  *   return DTRACE_IDNONE.
1842  *
1843  * 2.8.4  Caller's context
1844  *
1845  *   While dtrace_probe_lookup() is generally expected to be called from
1846  *   dtps_provide() and/or dtps_provide_module(), it may also be called from
1847  *   other non-DTrace contexts.  Neither cpu_lock nor mod_lock may be held.
1848  *
1849  * 2.9  void *dtrace_probe_arg(dtrace_provider_t id, dtrace_id_t probe)
1850  *
1851  * 2.9.1  Overview
1852  *
1853  *   Returns the probe argument associated with the specified probe.
1854  *
1855  * 2.9.2  Arguments and Notes
1856  *
1857  *   The first argument is the provider identifier, as returned from a
1858  *   successful call to dtrace_register().  The second argument is a probe
1859  *   identifier, as returned from dtrace_probe_lookup() or
1860  *   dtrace_probe_create().  This is useful if a probe has multiple
1861  *   provider-specific components to it:  the provider can create the probe
1862  *   once with provider-specific state, and then add to the state by looking
1863  *   up the probe based on probe identifier.
1864  *
1865  * 2.9.3  Return value
1866  *
1867  *   Returns the argument associated with the specified probe.  If the
1868  *   specified probe does not exist, or if the specified probe is not provided
1869  *   by the specified provider, NULL is returned.
1870  *
1871  * 2.9.4  Caller's context
1872  *
1873  *   While dtrace_probe_arg() is generally expected to be called from
1874  *   dtps_provide() and/or dtps_provide_module(), it may also be called from
1875  *   other non-DTrace contexts.  Neither cpu_lock nor mod_lock may be held.
1876  *
1877  * 2.10  void dtrace_probe(dtrace_id_t probe, uintptr_t arg0, uintptr_t arg1,
1878  *		uintptr_t arg2, uintptr_t arg3, uintptr_t arg4)
1879  *
1880  * 2.10.1  Overview
1881  *
1882  *   The epicenter of DTrace:  fires the specified probes with the specified
1883  *   arguments.
1884  *
1885  * 2.10.2  Arguments and Notes
1886  *
1887  *   The first argument is a probe identifier as returned by
1888  *   dtrace_probe_create() or dtrace_probe_lookup().  The second through sixth
1889  *   arguments are the values to which the D variables "arg0" through "arg4"
1890  *   will be mapped.
1891  *
1892  *   dtrace_probe() should be called whenever the specified probe has fired --
1893  *   however the provider defines it.
1894  *
1895  * 2.10.3  Return value
1896  *
1897  *   None.
1898  *
1899  * 2.10.4  Caller's context
1900  *
1901  *   dtrace_probe() may be called in virtually any context:  kernel, user,
1902  *   interrupt, high-level interrupt, with arbitrary adaptive locks held, with
1903  *   dispatcher locks held, with interrupts disabled, etc.  The only latitude
1904  *   that must be afforded to DTrace is the ability to make calls within
1905  *   itself (and to its in-kernel subroutines) and the ability to access
1906  *   arbitrary (but mapped) memory.  On some platforms, this constrains
1907  *   context.  For example, on UltraSPARC, dtrace_probe() cannot be called
1908  *   from any context in which TL is greater than zero.  dtrace_probe() may
1909  *   also not be called from any routine which may be called by dtrace_probe()
1910  *   -- which includes functions in the DTrace framework and some in-kernel
1911  *   DTrace subroutines.  All such functions "dtrace_"; providers that
1912  *   instrument the kernel arbitrarily should be sure to not instrument these
1913  *   routines.
1914  */
1915 typedef struct dtrace_pops {
1916 	void (*dtps_provide)(void *arg, const dtrace_probedesc_t *spec);
1917 	void (*dtps_provide_module)(void *arg, struct modctl *mp);
1918 	void (*dtps_enable)(void *arg, dtrace_id_t id, void *parg);
1919 	void (*dtps_disable)(void *arg, dtrace_id_t id, void *parg);
1920 	void (*dtps_suspend)(void *arg, dtrace_id_t id, void *parg);
1921 	void (*dtps_resume)(void *arg, dtrace_id_t id, void *parg);
1922 	void (*dtps_getargdesc)(void *arg, dtrace_id_t id, void *parg,
1923 	    dtrace_argdesc_t *desc);
1924 	uint64_t (*dtps_getargval)(void *arg, dtrace_id_t id, void *parg,
1925 	    int argno, int aframes);
1926 	int (*dtps_usermode)(void *arg, dtrace_id_t id, void *parg);
1927 	void (*dtps_destroy)(void *arg, dtrace_id_t id, void *parg);
1928 } dtrace_pops_t;
1929 
1930 typedef uintptr_t	dtrace_provider_id_t;
1931 
1932 extern int dtrace_register(const char *, const dtrace_pattr_t *, uint32_t,
1933     uid_t, const dtrace_pops_t *, void *, dtrace_provider_id_t *);
1934 extern int dtrace_unregister(dtrace_provider_id_t);
1935 extern int dtrace_condense(dtrace_provider_id_t);
1936 extern void dtrace_invalidate(dtrace_provider_id_t);
1937 extern dtrace_id_t dtrace_probe_lookup(dtrace_provider_id_t, const char *,
1938     const char *, const char *);
1939 extern dtrace_id_t dtrace_probe_create(dtrace_provider_id_t, const char *,
1940     const char *, const char *, int, void *);
1941 extern void *dtrace_probe_arg(dtrace_provider_id_t, dtrace_id_t);
1942 extern void dtrace_probe(dtrace_id_t, uintptr_t arg0, uintptr_t arg1,
1943     uintptr_t arg2, uintptr_t arg3, uintptr_t arg4);
1944 
1945 /*
1946  * DTrace Meta Provider API
1947  *
1948  * The following functions are implemented by the DTrace framework and are
1949  * used to implement meta providers. Meta providers plug into the DTrace
1950  * framework and are used to instantiate new providers on the fly. At
1951  * present, there is only one type of meta provider and only one meta
1952  * provider may be registered with the DTrace framework at a time. The
1953  * sole meta provider type provides user-land static tracing facilities
1954  * by taking meta probe descriptions and adding a corresponding provider
1955  * into the DTrace framework.
1956  *
1957  * 1 Framework-to-Provider
1958  *
1959  * 1.1 Overview
1960  *
1961  * The Framework-to-Provider API is represented by the dtrace_mops structure
1962  * that the meta provider passes to the framework when registering itself as
1963  * a meta provider. This structure consists of the following members:
1964  *
1965  *   dtms_create_probe()	<-- Add a new probe to a created provider
1966  *   dtms_provide_pid()		<-- Create a new provider for a given process
1967  *   dtms_remove_pid()		<-- Remove a previously created provider
1968  *
1969  * 1.2  void dtms_create_probe(void *arg, void *parg,
1970  *           dtrace_helper_probedesc_t *probedesc);
1971  *
1972  * 1.2.1  Overview
1973  *
1974  *   Called by the DTrace framework to create a new probe in a provider
1975  *   created by this meta provider.
1976  *
1977  * 1.2.2  Arguments and notes
1978  *
1979  *   The first argument is the cookie as passed to dtrace_meta_register().
1980  *   The second argument is the provider cookie for the associated provider;
1981  *   this is obtained from the return value of dtms_provide_pid(). The third
1982  *   argument is the helper probe description.
1983  *
1984  * 1.2.3  Return value
1985  *
1986  *   None
1987  *
1988  * 1.2.4  Caller's context
1989  *
1990  *   dtms_create_probe() is called from either ioctl() or module load context.
1991  *   The DTrace framework is locked in such a way that meta providers may not
1992  *   register or unregister. This means that the meta provider cannot call
1993  *   dtrace_meta_register() or dtrace_meta_unregister(). However, the context is
1994  *   such that the provider may (and is expected to) call provider-related
1995  *   DTrace provider APIs including dtrace_probe_create().
1996  *
1997  * 1.3  void *dtms_provide_pid(void *arg, dtrace_meta_provider_t *mprov,
1998  *	      pid_t pid)
1999  *
2000  * 1.3.1  Overview
2001  *
2002  *   Called by the DTrace framework to instantiate a new provider given the
2003  *   description of the provider and probes in the mprov argument. The
2004  *   meta provider should call dtrace_register() to insert the new provider
2005  *   into the DTrace framework.
2006  *
2007  * 1.3.2  Arguments and notes
2008  *
2009  *   The first argument is the cookie as passed to dtrace_meta_register().
2010  *   The second argument is a pointer to a structure describing the new
2011  *   helper provider. The third argument is the process identifier for
2012  *   process associated with this new provider. Note that the name of the
2013  *   provider as passed to dtrace_register() should be the contatenation of
2014  *   the dtmpb_provname member of the mprov argument and the processs
2015  *   identifier as a string.
2016  *
2017  * 1.3.3  Return value
2018  *
2019  *   The cookie for the provider that the meta provider creates. This is
2020  *   the same value that it passed to dtrace_register().
2021  *
2022  * 1.3.4  Caller's context
2023  *
2024  *   dtms_provide_pid() is called from either ioctl() or module load context.
2025  *   The DTrace framework is locked in such a way that meta providers may not
2026  *   register or unregister. This means that the meta provider cannot call
2027  *   dtrace_meta_register() or dtrace_meta_unregister(). However, the context
2028  *   is such that the provider may -- and is expected to --  call
2029  *   provider-related DTrace provider APIs including dtrace_register().
2030  *
2031  * 1.4  void dtms_remove_pid(void *arg, dtrace_meta_provider_t *mprov,
2032  *	     pid_t pid)
2033  *
2034  * 1.4.1  Overview
2035  *
2036  *   Called by the DTrace framework to remove a provider that had previously
2037  *   been instantiated via the dtms_provide_pid() entry point. The meta
2038  *   provider need not remove the provider immediately, but this entry
2039  *   point indicates that the provider should be removed as soon as possible
2040  *   using the dtrace_unregister() API.
2041  *
2042  * 1.4.2  Arguments and notes
2043  *
2044  *   The first argument is the cookie as passed to dtrace_meta_register().
2045  *   The second argument is a pointer to a structure describing the helper
2046  *   provider. The third argument is the process identifier for process
2047  *   associated with this new provider.
2048  *
2049  * 1.4.3  Return value
2050  *
2051  *   None
2052  *
2053  * 1.4.4  Caller's context
2054  *
2055  *   dtms_remove_pid() is called from either ioctl() or exit() context.
2056  *   The DTrace framework is locked in such a way that meta providers may not
2057  *   register or unregister. This means that the meta provider cannot call
2058  *   dtrace_meta_register() or dtrace_meta_unregister(). However, the context
2059  *   is such that the provider may -- and is expected to -- call
2060  *   provider-related DTrace provider APIs including dtrace_unregister().
2061  */
2062 typedef struct dtrace_helper_probedesc {
2063 	char *dthpb_mod;			/* probe module */
2064 	char *dthpb_func; 			/* probe function */
2065 	char *dthpb_name; 			/* probe name */
2066 	uint64_t dthpb_base;			/* base address */
2067 	uint32_t *dthpb_offs;			/* offsets array */
2068 	uint32_t dthpb_noffs;			/* offsets count */
2069 	uint8_t *dthpb_args;			/* argument mapping array */
2070 	uint8_t dthpb_xargc;			/* translated argument count */
2071 	uint8_t dthpb_nargc;			/* native argument count */
2072 	char *dthpb_xtypes;			/* translated types strings */
2073 	char *dthpb_ntypes;			/* native types strings */
2074 } dtrace_helper_probedesc_t;
2075 
2076 typedef struct dtrace_helper_provdesc {
2077 	char *dthpv_provname;			/* provider name */
2078 	dtrace_pattr_t dthpv_pattr;		/* stability attributes */
2079 } dtrace_helper_provdesc_t;
2080 
2081 typedef struct dtrace_mops {
2082 	void (*dtms_create_probe)(void *, void *, dtrace_helper_probedesc_t *);
2083 	void *(*dtms_provide_pid)(void *, dtrace_helper_provdesc_t *, pid_t);
2084 	void (*dtms_remove_pid)(void *, dtrace_helper_provdesc_t *, pid_t);
2085 } dtrace_mops_t;
2086 
2087 typedef uintptr_t	dtrace_meta_provider_id_t;
2088 
2089 extern int dtrace_meta_register(const char *, const dtrace_mops_t *, void *,
2090     dtrace_meta_provider_id_t *);
2091 extern int dtrace_meta_unregister(dtrace_meta_provider_id_t);
2092 
2093 /*
2094  * DTrace Kernel Hooks
2095  *
2096  * The following functions are implemented by the base kernel and form a set of
2097  * hooks used by the DTrace framework.  DTrace hooks are implemented in either
2098  * uts/common/os/dtrace_subr.c, an ISA-specific assembly file, or in a
2099  * uts/<platform>/os/dtrace_subr.c corresponding to each hardware platform.
2100  */
2101 
2102 typedef enum dtrace_vtime_state {
2103 	DTRACE_VTIME_INACTIVE = 0,	/* No DTrace, no TNF */
2104 	DTRACE_VTIME_ACTIVE,		/* DTrace virtual time, no TNF */
2105 	DTRACE_VTIME_INACTIVE_TNF,	/* No DTrace, TNF active */
2106 	DTRACE_VTIME_ACTIVE_TNF		/* DTrace virtual time _and_ TNF */
2107 } dtrace_vtime_state_t;
2108 
2109 extern dtrace_vtime_state_t dtrace_vtime_active;
2110 extern void dtrace_vtime_switch(kthread_t *next);
2111 extern void dtrace_vtime_enable_tnf(void);
2112 extern void dtrace_vtime_disable_tnf(void);
2113 extern void dtrace_vtime_enable(void);
2114 extern void dtrace_vtime_disable(void);
2115 
2116 struct regs;
2117 
2118 extern int (*dtrace_pid_probe_ptr)(struct regs *);
2119 extern int (*dtrace_fasttrap_probe_ptr)(struct regs *);
2120 extern int (*dtrace_return_probe_ptr)(struct regs *);
2121 extern void (*dtrace_fasttrap_fork_ptr)(proc_t *, proc_t *);
2122 extern void (*dtrace_fasttrap_exec_ptr)(proc_t *);
2123 extern void (*dtrace_fasttrap_exit_ptr)(proc_t *);
2124 extern void dtrace_fasttrap_fork(proc_t *, proc_t *);
2125 
2126 typedef uintptr_t dtrace_icookie_t;
2127 typedef void (*dtrace_xcall_t)(void *);
2128 
2129 extern dtrace_icookie_t dtrace_interrupt_disable(void);
2130 extern void dtrace_interrupt_enable(dtrace_icookie_t);
2131 
2132 extern void dtrace_membar_producer(void);
2133 extern void dtrace_membar_consumer(void);
2134 
2135 extern void (*dtrace_cpu_init)(processorid_t);
2136 extern void (*dtrace_modload)(struct modctl *);
2137 extern void (*dtrace_modunload)(struct modctl *);
2138 extern void (*dtrace_helpers_cleanup)();
2139 extern void (*dtrace_helpers_fork)(proc_t *parent, proc_t *child);
2140 extern void (*dtrace_cpustart_init)();
2141 extern void (*dtrace_cpustart_fini)();
2142 
2143 extern void (*dtrace_kreloc_init)();
2144 extern void (*dtrace_kreloc_fini)();
2145 
2146 extern void (*dtrace_debugger_init)();
2147 extern void (*dtrace_debugger_fini)();
2148 extern dtrace_cacheid_t dtrace_predcache_id;
2149 
2150 extern hrtime_t dtrace_gethrtime(void);
2151 extern void dtrace_sync(void);
2152 extern void dtrace_toxic_ranges(void (*)(uintptr_t, uintptr_t));
2153 extern void dtrace_xcall(processorid_t, dtrace_xcall_t, void *);
2154 extern void dtrace_vpanic(const char *, __va_list);
2155 extern void dtrace_panic(const char *, ...);
2156 
2157 extern int dtrace_safe_defer_signal(void);
2158 extern void dtrace_safe_synchronous_signal(void);
2159 
2160 #if defined(__i386) || defined(__amd64)
2161 extern int dtrace_instr_size(uchar_t *instr);
2162 extern int dtrace_instr_size_isa(uchar_t *, model_t, int *);
2163 extern void dtrace_invop_add(int (*)(uintptr_t, uintptr_t *, uintptr_t));
2164 extern void dtrace_invop_remove(int (*)(uintptr_t, uintptr_t *, uintptr_t));
2165 extern void dtrace_invop_callsite(void);
2166 #endif
2167 
2168 #ifdef __sparc
2169 extern int dtrace_blksuword32(uintptr_t, uint32_t *, int);
2170 extern void dtrace_getfsr(uint64_t *);
2171 #endif
2172 
2173 #define	DTRACE_CPUFLAG_ISSET(flag) \
2174 	(cpu_core[CPU->cpu_id].cpuc_dtrace_flags & (flag))
2175 
2176 #define	DTRACE_CPUFLAG_SET(flag) \
2177 	(cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= (flag))
2178 
2179 #define	DTRACE_CPUFLAG_CLEAR(flag) \
2180 	(cpu_core[CPU->cpu_id].cpuc_dtrace_flags &= ~(flag))
2181 
2182 #endif /* _KERNEL */
2183 
2184 #endif	/* _ASM */
2185 
2186 #if defined(__i386) || defined(__amd64)
2187 
2188 #define	DTRACE_INVOP_PUSHL_EBP		1
2189 #define	DTRACE_INVOP_POPL_EBP		2
2190 #define	DTRACE_INVOP_LEAVE		3
2191 #define	DTRACE_INVOP_NOP		4
2192 #define	DTRACE_INVOP_RET		5
2193 
2194 #endif
2195 
2196 #ifdef	__cplusplus
2197 }
2198 #endif
2199 
2200 #endif	/* _SYS_DTRACE_H */
2201