xref: /illumos-gate/usr/src/uts/common/sys/sysmacros.h (revision 5422785d352a2bb398daceab3d1898a8aa64d006)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
22 /*	  All Rights Reserved  	*/
23 
24 
25 /*
26  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
27  * Use is subject to license terms.
28  *
29  * Copyright 2011, 2012 Nexenta Systems, Inc.  All rights reserved.
30  */
31 
32 #ifndef _SYS_SYSMACROS_H
33 #define	_SYS_SYSMACROS_H
34 
35 #include <sys/param.h>
36 
37 #ifdef	__cplusplus
38 extern "C" {
39 #endif
40 
41 /*
42  * Some macros for units conversion
43  */
44 /*
45  * Disk blocks (sectors) and bytes.
46  */
47 #define	dtob(DD)	((DD) << DEV_BSHIFT)
48 #define	btod(BB)	(((BB) + DEV_BSIZE - 1) >> DEV_BSHIFT)
49 #define	btodt(BB)	((BB) >> DEV_BSHIFT)
50 #define	lbtod(BB)	(((offset_t)(BB) + DEV_BSIZE - 1) >> DEV_BSHIFT)
51 
52 /* common macros */
53 #ifndef MIN
54 #define	MIN(a, b)	((a) < (b) ? (a) : (b))
55 #endif
56 #ifndef MAX
57 #define	MAX(a, b)	((a) < (b) ? (b) : (a))
58 #endif
59 #ifndef ABS
60 #define	ABS(a)		((a) < 0 ? -(a) : (a))
61 #endif
62 #ifndef	SIGNOF
63 #define	SIGNOF(a)	((a) < 0 ? -1 : (a) > 0)
64 #endif
65 
66 #ifdef _KERNEL
67 
68 /*
69  * Convert a single byte to/from binary-coded decimal (BCD).
70  */
71 extern unsigned char byte_to_bcd[256];
72 extern unsigned char bcd_to_byte[256];
73 
74 #define	BYTE_TO_BCD(x)	byte_to_bcd[(x) & 0xff]
75 #define	BCD_TO_BYTE(x)	bcd_to_byte[(x) & 0xff]
76 
77 #endif	/* _KERNEL */
78 
79 /*
80  * WARNING: The device number macros defined here should not be used by device
81  * drivers or user software. Device drivers should use the device functions
82  * defined in the DDI/DKI interface (see also ddi.h). Application software
83  * should make use of the library routines available in makedev(3). A set of
84  * new device macros are provided to operate on the expanded device number
85  * format supported in SVR4. Macro versions of the DDI device functions are
86  * provided for use by kernel proper routines only. Macro routines bmajor(),
87  * major(), minor(), emajor(), eminor(), and makedev() will be removed or
88  * their definitions changed at the next major release following SVR4.
89  */
90 
91 #define	O_BITSMAJOR	7	/* # of SVR3 major device bits */
92 #define	O_BITSMINOR	8	/* # of SVR3 minor device bits */
93 #define	O_MAXMAJ	0x7f	/* SVR3 max major value */
94 #define	O_MAXMIN	0xff	/* SVR3 max minor value */
95 
96 
97 #define	L_BITSMAJOR32	14	/* # of SVR4 major device bits */
98 #define	L_BITSMINOR32	18	/* # of SVR4 minor device bits */
99 #define	L_MAXMAJ32	0x3fff	/* SVR4 max major value */
100 #define	L_MAXMIN32	0x3ffff	/* MAX minor for 3b2 software drivers. */
101 				/* For 3b2 hardware devices the minor is */
102 				/* restricted to 256 (0-255) */
103 
104 #ifdef _LP64
105 #define	L_BITSMAJOR	32	/* # of major device bits in 64-bit Solaris */
106 #define	L_BITSMINOR	32	/* # of minor device bits in 64-bit Solaris */
107 #define	L_MAXMAJ	0xfffffffful	/* max major value */
108 #define	L_MAXMIN	0xfffffffful	/* max minor value */
109 #else
110 #define	L_BITSMAJOR	L_BITSMAJOR32
111 #define	L_BITSMINOR	L_BITSMINOR32
112 #define	L_MAXMAJ	L_MAXMAJ32
113 #define	L_MAXMIN	L_MAXMIN32
114 #endif
115 
116 #ifdef _KERNEL
117 
118 /* major part of a device internal to the kernel */
119 
120 #define	major(x)	(major_t)((((unsigned)(x)) >> O_BITSMINOR) & O_MAXMAJ)
121 #define	bmajor(x)	(major_t)((((unsigned)(x)) >> O_BITSMINOR) & O_MAXMAJ)
122 
123 /* get internal major part of expanded device number */
124 
125 #define	getmajor(x)	(major_t)((((dev_t)(x)) >> L_BITSMINOR) & L_MAXMAJ)
126 
127 /* minor part of a device internal to the kernel */
128 
129 #define	minor(x)	(minor_t)((x) & O_MAXMIN)
130 
131 /* get internal minor part of expanded device number */
132 
133 #define	getminor(x)	(minor_t)((x) & L_MAXMIN)
134 
135 #else
136 
137 /* major part of a device external from the kernel (same as emajor below) */
138 
139 #define	major(x)	(major_t)((((unsigned)(x)) >> O_BITSMINOR) & O_MAXMAJ)
140 
141 /* minor part of a device external from the kernel  (same as eminor below) */
142 
143 #define	minor(x)	(minor_t)((x) & O_MAXMIN)
144 
145 #endif	/* _KERNEL */
146 
147 /* create old device number */
148 
149 #define	makedev(x, y) (unsigned short)(((x) << O_BITSMINOR) | ((y) & O_MAXMIN))
150 
151 /* make an new device number */
152 
153 #define	makedevice(x, y) (dev_t)(((dev_t)(x) << L_BITSMINOR) | ((y) & L_MAXMIN))
154 
155 
156 /*
157  * emajor() allows kernel/driver code to print external major numbers
158  * eminor() allows kernel/driver code to print external minor numbers
159  */
160 
161 #define	emajor(x) \
162 	(major_t)(((unsigned int)(x) >> O_BITSMINOR) > O_MAXMAJ) ? \
163 	    NODEV : (((unsigned int)(x) >> O_BITSMINOR) & O_MAXMAJ)
164 
165 #define	eminor(x) \
166 	(minor_t)((x) & O_MAXMIN)
167 
168 /*
169  * get external major and minor device
170  * components from expanded device number
171  */
172 #define	getemajor(x)	(major_t)((((dev_t)(x) >> L_BITSMINOR) > L_MAXMAJ) ? \
173 			    NODEV : (((dev_t)(x) >> L_BITSMINOR) & L_MAXMAJ))
174 #define	geteminor(x)	(minor_t)((x) & L_MAXMIN)
175 
176 /*
177  * These are versions of the kernel routines for compressing and
178  * expanding long device numbers that don't return errors.
179  */
180 #if (L_BITSMAJOR32 == L_BITSMAJOR) && (L_BITSMINOR32 == L_BITSMINOR)
181 
182 #define	DEVCMPL(x)	(x)
183 #define	DEVEXPL(x)	(x)
184 
185 #else
186 
187 #define	DEVCMPL(x)	\
188 	(dev32_t)((((x) >> L_BITSMINOR) > L_MAXMAJ32 || \
189 	    ((x) & L_MAXMIN) > L_MAXMIN32) ? NODEV32 : \
190 	    ((((x) >> L_BITSMINOR) << L_BITSMINOR32) | ((x) & L_MAXMIN32)))
191 
192 #define	DEVEXPL(x)	\
193 	(((x) == NODEV32) ? NODEV : \
194 	makedevice(((x) >> L_BITSMINOR32) & L_MAXMAJ32, (x) & L_MAXMIN32))
195 
196 #endif /* L_BITSMAJOR32 ... */
197 
198 /* convert to old (SVR3.2) dev format */
199 
200 #define	cmpdev(x) \
201 	(o_dev_t)((((x) >> L_BITSMINOR) > O_MAXMAJ || \
202 	    ((x) & L_MAXMIN) > O_MAXMIN) ? NODEV : \
203 	    ((((x) >> L_BITSMINOR) << O_BITSMINOR) | ((x) & O_MAXMIN)))
204 
205 /* convert to new (SVR4) dev format */
206 
207 #define	expdev(x) \
208 	(dev_t)(((dev_t)(((x) >> O_BITSMINOR) & O_MAXMAJ) << L_BITSMINOR) | \
209 	    ((x) & O_MAXMIN))
210 
211 /*
212  * Macro for checking power of 2 address alignment.
213  */
214 #define	IS_P2ALIGNED(v, a) ((((uintptr_t)(v)) & ((uintptr_t)(a) - 1)) == 0)
215 
216 /*
217  * Macros for counting and rounding.
218  */
219 #define	howmany(x, y)	(((x)+((y)-1))/(y))
220 #define	roundup(x, y)	((((x)+((y)-1))/(y))*(y))
221 
222 /*
223  * Macro to determine if value is a power of 2
224  */
225 #define	ISP2(x)		(((x) & ((x) - 1)) == 0)
226 
227 /*
228  * Macros for various sorts of alignment and rounding.  The "align" must
229  * be a power of 2.  Often times it is a block, sector, or page.
230  */
231 
232 /*
233  * return x rounded down to an align boundary
234  * eg, P2ALIGN(1200, 1024) == 1024 (1*align)
235  * eg, P2ALIGN(1024, 1024) == 1024 (1*align)
236  * eg, P2ALIGN(0x1234, 0x100) == 0x1200 (0x12*align)
237  * eg, P2ALIGN(0x5600, 0x100) == 0x5600 (0x56*align)
238  */
239 #define	P2ALIGN(x, align)		((x) & -(align))
240 
241 /*
242  * return x % (mod) align
243  * eg, P2PHASE(0x1234, 0x100) == 0x34 (x-0x12*align)
244  * eg, P2PHASE(0x5600, 0x100) == 0x00 (x-0x56*align)
245  */
246 #define	P2PHASE(x, align)		((x) & ((align) - 1))
247 
248 /*
249  * return how much space is left in this block (but if it's perfectly
250  * aligned, return 0).
251  * eg, P2NPHASE(0x1234, 0x100) == 0xcc (0x13*align-x)
252  * eg, P2NPHASE(0x5600, 0x100) == 0x00 (0x56*align-x)
253  */
254 #define	P2NPHASE(x, align)		(-(x) & ((align) - 1))
255 
256 /*
257  * return x rounded up to an align boundary
258  * eg, P2ROUNDUP(0x1234, 0x100) == 0x1300 (0x13*align)
259  * eg, P2ROUNDUP(0x5600, 0x100) == 0x5600 (0x56*align)
260  */
261 #define	P2ROUNDUP(x, align)		(-(-(x) & -(align)))
262 
263 /*
264  * return the ending address of the block that x is in
265  * eg, P2END(0x1234, 0x100) == 0x12ff (0x13*align - 1)
266  * eg, P2END(0x5600, 0x100) == 0x56ff (0x57*align - 1)
267  */
268 #define	P2END(x, align)			(-(~(x) & -(align)))
269 
270 /*
271  * return x rounded up to the next phase (offset) within align.
272  * phase should be < align.
273  * eg, P2PHASEUP(0x1234, 0x100, 0x10) == 0x1310 (0x13*align + phase)
274  * eg, P2PHASEUP(0x5600, 0x100, 0x10) == 0x5610 (0x56*align + phase)
275  */
276 #define	P2PHASEUP(x, align, phase)	((phase) - (((phase) - (x)) & -(align)))
277 
278 /*
279  * return TRUE if adding len to off would cause it to cross an align
280  * boundary.
281  * eg, P2BOUNDARY(0x1234, 0xe0, 0x100) == TRUE (0x1234 + 0xe0 == 0x1314)
282  * eg, P2BOUNDARY(0x1234, 0x50, 0x100) == FALSE (0x1234 + 0x50 == 0x1284)
283  */
284 #define	P2BOUNDARY(off, len, align) \
285 	(((off) ^ ((off) + (len) - 1)) > (align) - 1)
286 
287 /*
288  * Return TRUE if they have the same highest bit set.
289  * eg, P2SAMEHIGHBIT(0x1234, 0x1001) == TRUE (the high bit is 0x1000)
290  * eg, P2SAMEHIGHBIT(0x1234, 0x3010) == FALSE (high bit of 0x3010 is 0x2000)
291  */
292 #define	P2SAMEHIGHBIT(x, y)		(((x) ^ (y)) < ((x) & (y)))
293 
294 /*
295  * Typed version of the P2* macros.  These macros should be used to ensure
296  * that the result is correctly calculated based on the data type of (x),
297  * which is passed in as the last argument, regardless of the data
298  * type of the alignment.  For example, if (x) is of type uint64_t,
299  * and we want to round it up to a page boundary using "PAGESIZE" as
300  * the alignment, we can do either
301  *	P2ROUNDUP(x, (uint64_t)PAGESIZE)
302  * or
303  *	P2ROUNDUP_TYPED(x, PAGESIZE, uint64_t)
304  */
305 #define	P2ALIGN_TYPED(x, align, type)	\
306 	((type)(x) & -(type)(align))
307 #define	P2PHASE_TYPED(x, align, type)	\
308 	((type)(x) & ((type)(align) - 1))
309 #define	P2NPHASE_TYPED(x, align, type)	\
310 	(-(type)(x) & ((type)(align) - 1))
311 #define	P2ROUNDUP_TYPED(x, align, type)	\
312 	(-(-(type)(x) & -(type)(align)))
313 #define	P2END_TYPED(x, align, type)	\
314 	(-(~(type)(x) & -(type)(align)))
315 #define	P2PHASEUP_TYPED(x, align, phase, type)	\
316 	((type)(phase) - (((type)(phase) - (type)(x)) & -(type)(align)))
317 #define	P2CROSS_TYPED(x, y, align, type)	\
318 	(((type)(x) ^ (type)(y)) > (type)(align) - 1)
319 #define	P2SAMEHIGHBIT_TYPED(x, y, type) \
320 	(((type)(x) ^ (type)(y)) < ((type)(x) & (type)(y)))
321 
322 /*
323  * Macros to atomically increment/decrement a variable.  mutex and var
324  * must be pointers.
325  */
326 #define	INCR_COUNT(var, mutex) mutex_enter(mutex), (*(var))++, mutex_exit(mutex)
327 #define	DECR_COUNT(var, mutex) mutex_enter(mutex), (*(var))--, mutex_exit(mutex)
328 
329 /*
330  * Macros to declare bitfields - the order in the parameter list is
331  * Low to High - that is, declare bit 0 first.  We only support 8-bit bitfields
332  * because if a field crosses a byte boundary it's not likely to be meaningful
333  * without reassembly in its nonnative endianness.
334  */
335 #if defined(_BIT_FIELDS_LTOH)
336 #define	DECL_BITFIELD2(_a, _b)				\
337 	uint8_t _a, _b
338 #define	DECL_BITFIELD3(_a, _b, _c)			\
339 	uint8_t _a, _b, _c
340 #define	DECL_BITFIELD4(_a, _b, _c, _d)			\
341 	uint8_t _a, _b, _c, _d
342 #define	DECL_BITFIELD5(_a, _b, _c, _d, _e)		\
343 	uint8_t _a, _b, _c, _d, _e
344 #define	DECL_BITFIELD6(_a, _b, _c, _d, _e, _f)		\
345 	uint8_t _a, _b, _c, _d, _e, _f
346 #define	DECL_BITFIELD7(_a, _b, _c, _d, _e, _f, _g)	\
347 	uint8_t _a, _b, _c, _d, _e, _f, _g
348 #define	DECL_BITFIELD8(_a, _b, _c, _d, _e, _f, _g, _h)	\
349 	uint8_t _a, _b, _c, _d, _e, _f, _g, _h
350 #elif defined(_BIT_FIELDS_HTOL)
351 #define	DECL_BITFIELD2(_a, _b)				\
352 	uint8_t _b, _a
353 #define	DECL_BITFIELD3(_a, _b, _c)			\
354 	uint8_t _c, _b, _a
355 #define	DECL_BITFIELD4(_a, _b, _c, _d)			\
356 	uint8_t _d, _c, _b, _a
357 #define	DECL_BITFIELD5(_a, _b, _c, _d, _e)		\
358 	uint8_t _e, _d, _c, _b, _a
359 #define	DECL_BITFIELD6(_a, _b, _c, _d, _e, _f)		\
360 	uint8_t _f, _e, _d, _c, _b, _a
361 #define	DECL_BITFIELD7(_a, _b, _c, _d, _e, _f, _g)	\
362 	uint8_t _g, _f, _e, _d, _c, _b, _a
363 #define	DECL_BITFIELD8(_a, _b, _c, _d, _e, _f, _g, _h)	\
364 	uint8_t _h, _g, _f, _e, _d, _c, _b, _a
365 #else
366 #error	One of _BIT_FIELDS_LTOH or _BIT_FIELDS_HTOL must be defined
367 #endif  /* _BIT_FIELDS_LTOH */
368 
369 /* avoid any possibility of clashing with <stddef.h> version */
370 #if defined(_KERNEL) && !defined(_KMEMUSER)
371 
372 #if !defined(offsetof)
373 #define	offsetof(s, m)	((size_t)(&(((s *)0)->m)))
374 #endif /* !offsetof */
375 
376 #define	container_of(m, s, name)			\
377 	(void *)((uintptr_t)(m) - (uintptr_t)offsetof(s, name))
378 
379 #define	ARRAY_SIZE(x)	(sizeof (x) / sizeof (x[0]))
380 #endif /* _KERNEL, !_KMEMUSER */
381 
382 #ifdef	__cplusplus
383 }
384 #endif
385 
386 #endif	/* _SYS_SYSMACROS_H */
387