xref: /illumos-gate/usr/src/uts/common/sys/sysmacros.h (revision d1aea6f139360e9e7f1504facb24f8521047b15c)
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 2013 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 #include <sys/stddef.h>
37 
38 #ifdef	__cplusplus
39 extern "C" {
40 #endif
41 
42 /*
43  * Some macros for units conversion
44  */
45 /*
46  * Disk blocks (sectors) and bytes.
47  */
48 #define	dtob(DD)	((DD) << DEV_BSHIFT)
49 #define	btod(BB)	(((BB) + DEV_BSIZE - 1) >> DEV_BSHIFT)
50 #define	btodt(BB)	((BB) >> DEV_BSHIFT)
51 #define	lbtod(BB)	(((offset_t)(BB) + DEV_BSIZE - 1) >> DEV_BSHIFT)
52 
53 /* common macros */
54 #ifndef MIN
55 #define	MIN(a, b)	((a) < (b) ? (a) : (b))
56 #endif
57 #ifndef MAX
58 #define	MAX(a, b)	((a) < (b) ? (b) : (a))
59 #endif
60 #ifndef ABS
61 #define	ABS(a)		((a) < 0 ? -(a) : (a))
62 #endif
63 #ifndef	SIGNOF
64 #define	SIGNOF(a)	((a) < 0 ? -1 : (a) > 0)
65 #endif
66 
67 #ifdef _KERNEL
68 
69 /*
70  * Convert a single byte to/from binary-coded decimal (BCD).
71  */
72 extern unsigned char byte_to_bcd[256];
73 extern unsigned char bcd_to_byte[256];
74 
75 #define	BYTE_TO_BCD(x)	byte_to_bcd[(x) & 0xff]
76 #define	BCD_TO_BYTE(x)	bcd_to_byte[(x) & 0xff]
77 
78 #endif	/* _KERNEL */
79 
80 /*
81  * WARNING: The device number macros defined here should not be used by device
82  * drivers or user software. Device drivers should use the device functions
83  * defined in the DDI/DKI interface (see also ddi.h). Application software
84  * should make use of the library routines available in makedev(3). A set of
85  * new device macros are provided to operate on the expanded device number
86  * format supported in SVR4. Macro versions of the DDI device functions are
87  * provided for use by kernel proper routines only. Macro routines bmajor(),
88  * major(), minor(), emajor(), eminor(), and makedev() will be removed or
89  * their definitions changed at the next major release following SVR4.
90  */
91 
92 #define	O_BITSMAJOR	7	/* # of SVR3 major device bits */
93 #define	O_BITSMINOR	8	/* # of SVR3 minor device bits */
94 #define	O_MAXMAJ	0x7f	/* SVR3 max major value */
95 #define	O_MAXMIN	0xff	/* SVR3 max minor value */
96 
97 
98 #define	L_BITSMAJOR32	14	/* # of SVR4 major device bits */
99 #define	L_BITSMINOR32	18	/* # of SVR4 minor device bits */
100 #define	L_MAXMAJ32	0x3fff	/* SVR4 max major value */
101 #define	L_MAXMIN32	0x3ffff	/* MAX minor for 3b2 software drivers. */
102 				/* For 3b2 hardware devices the minor is */
103 				/* restricted to 256 (0-255) */
104 
105 #ifdef _LP64
106 #define	L_BITSMAJOR	32	/* # of major device bits in 64-bit Solaris */
107 #define	L_BITSMINOR	32	/* # of minor device bits in 64-bit Solaris */
108 #define	L_MAXMAJ	0xfffffffful	/* max major value */
109 #define	L_MAXMIN	0xfffffffful	/* max minor value */
110 #else
111 #define	L_BITSMAJOR	L_BITSMAJOR32
112 #define	L_BITSMINOR	L_BITSMINOR32
113 #define	L_MAXMAJ	L_MAXMAJ32
114 #define	L_MAXMIN	L_MAXMIN32
115 #endif
116 
117 #ifdef _KERNEL
118 
119 /* major part of a device internal to the kernel */
120 
121 #define	major(x)	(major_t)((((unsigned)(x)) >> O_BITSMINOR) & O_MAXMAJ)
122 #define	bmajor(x)	(major_t)((((unsigned)(x)) >> O_BITSMINOR) & O_MAXMAJ)
123 
124 /* get internal major part of expanded device number */
125 
126 #define	getmajor(x)	(major_t)((((dev_t)(x)) >> L_BITSMINOR) & L_MAXMAJ)
127 
128 /* minor part of a device internal to the kernel */
129 
130 #define	minor(x)	(minor_t)((x) & O_MAXMIN)
131 
132 /* get internal minor part of expanded device number */
133 
134 #define	getminor(x)	(minor_t)((x) & L_MAXMIN)
135 
136 #else	/* _KERNEL */
137 
138 /* major part of a device external from the kernel (same as emajor below) */
139 
140 #define	major(x)	(major_t)((((unsigned)(x)) >> O_BITSMINOR) & O_MAXMAJ)
141 
142 /* minor part of a device external from the kernel  (same as eminor below) */
143 
144 #define	minor(x)	(minor_t)((x) & O_MAXMIN)
145 
146 #endif	/* _KERNEL */
147 
148 /* create old device number */
149 
150 #define	makedev(x, y) (unsigned short)(((x) << O_BITSMINOR) | ((y) & O_MAXMIN))
151 
152 /* make an new device number */
153 
154 #define	makedevice(x, y) (dev_t)(((dev_t)(x) << L_BITSMINOR) | ((y) & L_MAXMIN))
155 
156 
157 /*
158  * emajor() allows kernel/driver code to print external major numbers
159  * eminor() allows kernel/driver code to print external minor numbers
160  */
161 
162 #define	emajor(x) \
163 	(major_t)(((unsigned int)(x) >> O_BITSMINOR) > O_MAXMAJ) ? \
164 	    NODEV : (((unsigned int)(x) >> O_BITSMINOR) & O_MAXMAJ)
165 
166 #define	eminor(x) \
167 	(minor_t)((x) & O_MAXMIN)
168 
169 /*
170  * get external major and minor device
171  * components from expanded device number
172  */
173 #define	getemajor(x)	(major_t)((((dev_t)(x) >> L_BITSMINOR) > L_MAXMAJ) ? \
174 			    NODEV : (((dev_t)(x) >> L_BITSMINOR) & L_MAXMAJ))
175 #define	geteminor(x)	(minor_t)((x) & L_MAXMIN)
176 
177 /*
178  * These are versions of the kernel routines for compressing and
179  * expanding long device numbers that don't return errors.
180  */
181 #if (L_BITSMAJOR32 == L_BITSMAJOR) && (L_BITSMINOR32 == L_BITSMINOR)
182 
183 #define	DEVCMPL(x)	(x)
184 #define	DEVEXPL(x)	(x)
185 
186 #else
187 
188 #define	DEVCMPL(x)	\
189 	(dev32_t)((((x) >> L_BITSMINOR) > L_MAXMAJ32 || \
190 	    ((x) & L_MAXMIN) > L_MAXMIN32) ? NODEV32 : \
191 	    ((((x) >> L_BITSMINOR) << L_BITSMINOR32) | ((x) & L_MAXMIN32)))
192 
193 #define	DEVEXPL(x)	\
194 	(((x) == NODEV32) ? NODEV : \
195 	makedevice(((x) >> L_BITSMINOR32) & L_MAXMAJ32, (x) & L_MAXMIN32))
196 
197 #endif /* L_BITSMAJOR32 ... */
198 
199 /* convert to old (SVR3.2) dev format */
200 
201 #define	cmpdev(x) \
202 	(o_dev_t)((((x) >> L_BITSMINOR) > O_MAXMAJ || \
203 	    ((x) & L_MAXMIN) > O_MAXMIN) ? NODEV : \
204 	    ((((x) >> L_BITSMINOR) << O_BITSMINOR) | ((x) & O_MAXMIN)))
205 
206 /* convert to new (SVR4) dev format */
207 
208 #define	expdev(x) \
209 	(dev_t)(((dev_t)(((x) >> O_BITSMINOR) & O_MAXMAJ) << L_BITSMINOR) | \
210 	    ((x) & O_MAXMIN))
211 
212 /*
213  * Macro for checking power of 2 address alignment.
214  */
215 #define	IS_P2ALIGNED(v, a) ((((uintptr_t)(v)) & ((uintptr_t)(a) - 1)) == 0)
216 
217 /*
218  * Macros for counting and rounding.
219  */
220 #define	howmany(x, y)	(((x)+((y)-1))/(y))
221 #define	roundup(x, y)	((((x)+((y)-1))/(y))*(y))
222 
223 /*
224  * Macro to determine if value is a power of 2
225  */
226 #define	ISP2(x)		(((x) & ((x) - 1)) == 0)
227 
228 /*
229  * Macros for various sorts of alignment and rounding.  The "align" must
230  * be a power of 2.  Often times it is a block, sector, or page.
231  */
232 
233 /*
234  * return x rounded down to an align boundary
235  * eg, P2ALIGN(1200, 1024) == 1024 (1*align)
236  * eg, P2ALIGN(1024, 1024) == 1024 (1*align)
237  * eg, P2ALIGN(0x1234, 0x100) == 0x1200 (0x12*align)
238  * eg, P2ALIGN(0x5600, 0x100) == 0x5600 (0x56*align)
239  */
240 #define	P2ALIGN(x, align)		((x) & -(align))
241 
242 /*
243  * return x % (mod) align
244  * eg, P2PHASE(0x1234, 0x100) == 0x34 (x-0x12*align)
245  * eg, P2PHASE(0x5600, 0x100) == 0x00 (x-0x56*align)
246  */
247 #define	P2PHASE(x, align)		((x) & ((align) - 1))
248 
249 /*
250  * return how much space is left in this block (but if it's perfectly
251  * aligned, return 0).
252  * eg, P2NPHASE(0x1234, 0x100) == 0xcc (0x13*align-x)
253  * eg, P2NPHASE(0x5600, 0x100) == 0x00 (0x56*align-x)
254  */
255 #define	P2NPHASE(x, align)		(-(x) & ((align) - 1))
256 
257 /*
258  * return x rounded up to an align boundary
259  * eg, P2ROUNDUP(0x1234, 0x100) == 0x1300 (0x13*align)
260  * eg, P2ROUNDUP(0x5600, 0x100) == 0x5600 (0x56*align)
261  */
262 #define	P2ROUNDUP(x, align)		(-(-(x) & -(align)))
263 
264 /*
265  * return the ending address of the block that x is in
266  * eg, P2END(0x1234, 0x100) == 0x12ff (0x13*align - 1)
267  * eg, P2END(0x5600, 0x100) == 0x56ff (0x57*align - 1)
268  */
269 #define	P2END(x, align)			(-(~(x) & -(align)))
270 
271 /*
272  * return x rounded up to the next phase (offset) within align.
273  * phase should be < align.
274  * eg, P2PHASEUP(0x1234, 0x100, 0x10) == 0x1310 (0x13*align + phase)
275  * eg, P2PHASEUP(0x5600, 0x100, 0x10) == 0x5610 (0x56*align + phase)
276  */
277 #define	P2PHASEUP(x, align, phase)	((phase) - (((phase) - (x)) & -(align)))
278 
279 /*
280  * return TRUE if adding len to off would cause it to cross an align
281  * boundary.
282  * eg, P2BOUNDARY(0x1234, 0xe0, 0x100) == TRUE (0x1234 + 0xe0 == 0x1314)
283  * eg, P2BOUNDARY(0x1234, 0x50, 0x100) == FALSE (0x1234 + 0x50 == 0x1284)
284  */
285 #define	P2BOUNDARY(off, len, align) \
286 	(((off) ^ ((off) + (len) - 1)) > (align) - 1)
287 
288 /*
289  * Return TRUE if they have the same highest bit set.
290  * eg, P2SAMEHIGHBIT(0x1234, 0x1001) == TRUE (the high bit is 0x1000)
291  * eg, P2SAMEHIGHBIT(0x1234, 0x3010) == FALSE (high bit of 0x3010 is 0x2000)
292  */
293 #define	P2SAMEHIGHBIT(x, y)		(((x) ^ (y)) < ((x) & (y)))
294 
295 /*
296  * Typed version of the P2* macros.  These macros should be used to ensure
297  * that the result is correctly calculated based on the data type of (x),
298  * which is passed in as the last argument, regardless of the data
299  * type of the alignment.  For example, if (x) is of type uint64_t,
300  * and we want to round it up to a page boundary using "PAGESIZE" as
301  * the alignment, we can do either
302  *	P2ROUNDUP(x, (uint64_t)PAGESIZE)
303  * or
304  *	P2ROUNDUP_TYPED(x, PAGESIZE, uint64_t)
305  */
306 #define	P2ALIGN_TYPED(x, align, type)	\
307 	((type)(x) & -(type)(align))
308 #define	P2PHASE_TYPED(x, align, type)	\
309 	((type)(x) & ((type)(align) - 1))
310 #define	P2NPHASE_TYPED(x, align, type)	\
311 	(-(type)(x) & ((type)(align) - 1))
312 #define	P2ROUNDUP_TYPED(x, align, type)	\
313 	(-(-(type)(x) & -(type)(align)))
314 #define	P2END_TYPED(x, align, type)	\
315 	(-(~(type)(x) & -(type)(align)))
316 #define	P2PHASEUP_TYPED(x, align, phase, type)	\
317 	((type)(phase) - (((type)(phase) - (type)(x)) & -(type)(align)))
318 #define	P2CROSS_TYPED(x, y, align, type)	\
319 	(((type)(x) ^ (type)(y)) > (type)(align) - 1)
320 #define	P2SAMEHIGHBIT_TYPED(x, y, type) \
321 	(((type)(x) ^ (type)(y)) < ((type)(x) & (type)(y)))
322 
323 /*
324  * Macros to atomically increment/decrement a variable.  mutex and var
325  * must be pointers.
326  */
327 #define	INCR_COUNT(var, mutex) mutex_enter(mutex), (*(var))++, mutex_exit(mutex)
328 #define	DECR_COUNT(var, mutex) mutex_enter(mutex), (*(var))--, mutex_exit(mutex)
329 
330 /*
331  * Macros to declare bitfields - the order in the parameter list is
332  * Low to High - that is, declare bit 0 first.  We only support 8-bit bitfields
333  * because if a field crosses a byte boundary it's not likely to be meaningful
334  * without reassembly in its nonnative endianness.
335  */
336 #if defined(_BIT_FIELDS_LTOH)
337 #define	DECL_BITFIELD2(_a, _b)				\
338 	uint8_t _a, _b
339 #define	DECL_BITFIELD3(_a, _b, _c)			\
340 	uint8_t _a, _b, _c
341 #define	DECL_BITFIELD4(_a, _b, _c, _d)			\
342 	uint8_t _a, _b, _c, _d
343 #define	DECL_BITFIELD5(_a, _b, _c, _d, _e)		\
344 	uint8_t _a, _b, _c, _d, _e
345 #define	DECL_BITFIELD6(_a, _b, _c, _d, _e, _f)		\
346 	uint8_t _a, _b, _c, _d, _e, _f
347 #define	DECL_BITFIELD7(_a, _b, _c, _d, _e, _f, _g)	\
348 	uint8_t _a, _b, _c, _d, _e, _f, _g
349 #define	DECL_BITFIELD8(_a, _b, _c, _d, _e, _f, _g, _h)	\
350 	uint8_t _a, _b, _c, _d, _e, _f, _g, _h
351 #elif defined(_BIT_FIELDS_HTOL)
352 #define	DECL_BITFIELD2(_a, _b)				\
353 	uint8_t _b, _a
354 #define	DECL_BITFIELD3(_a, _b, _c)			\
355 	uint8_t _c, _b, _a
356 #define	DECL_BITFIELD4(_a, _b, _c, _d)			\
357 	uint8_t _d, _c, _b, _a
358 #define	DECL_BITFIELD5(_a, _b, _c, _d, _e)		\
359 	uint8_t _e, _d, _c, _b, _a
360 #define	DECL_BITFIELD6(_a, _b, _c, _d, _e, _f)		\
361 	uint8_t _f, _e, _d, _c, _b, _a
362 #define	DECL_BITFIELD7(_a, _b, _c, _d, _e, _f, _g)	\
363 	uint8_t _g, _f, _e, _d, _c, _b, _a
364 #define	DECL_BITFIELD8(_a, _b, _c, _d, _e, _f, _g, _h)	\
365 	uint8_t _h, _g, _f, _e, _d, _c, _b, _a
366 #else
367 #error	One of _BIT_FIELDS_LTOH or _BIT_FIELDS_HTOL must be defined
368 #endif  /* _BIT_FIELDS_LTOH */
369 
370 /* avoid any possibility of clashing with <stddef.h> version */
371 #if (defined(_KERNEL) || defined(_FAKE_KERNEL)) && !defined(_KMEMUSER)
372 
373 #define	ARRAY_SIZE(x)	(sizeof (x) / sizeof (x[0]))
374 
375 #endif /* _KERNEL, !_KMEMUSER */
376 
377 #ifdef	__cplusplus
378 }
379 #endif
380 
381 #endif	/* _SYS_SYSMACROS_H */
382