xref: /titanic_41/usr/src/uts/common/sys/sysmacros.h (revision ea8dc4b6d2251b437950c0056bc626b311c73c27)
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 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
23 /*	  All Rights Reserved  	*/
24 
25 
26 /*
27  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
28  * Use is subject to license terms.
29  */
30 
31 #ifndef _SYS_SYSMACROS_H
32 #define	_SYS_SYSMACROS_H
33 
34 #pragma ident	"%Z%%M%	%I%	%E% SMI"
35 
36 #include <sys/param.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 
64 #ifdef _KERNEL
65 
66 /*
67  * Convert a single byte to/from binary-coded decimal (BCD).
68  */
69 extern unsigned char byte_to_bcd[256];
70 extern unsigned char bcd_to_byte[256];
71 
72 #define	BYTE_TO_BCD(x)	byte_to_bcd[(x) & 0xff]
73 #define	BCD_TO_BYTE(x)	bcd_to_byte[(x) & 0xff]
74 
75 #endif	/* _KERNEL */
76 
77 /*
78  * WARNING: The device number macros defined here should not be used by device
79  * drivers or user software. Device drivers should use the device functions
80  * defined in the DDI/DKI interface (see also ddi.h). Application software
81  * should make use of the library routines available in makedev(3). A set of
82  * new device macros are provided to operate on the expanded device number
83  * format supported in SVR4. Macro versions of the DDI device functions are
84  * provided for use by kernel proper routines only. Macro routines bmajor(),
85  * major(), minor(), emajor(), eminor(), and makedev() will be removed or
86  * their definitions changed at the next major release following SVR4.
87  */
88 
89 #define	O_BITSMAJOR	7	/* # of SVR3 major device bits */
90 #define	O_BITSMINOR	8	/* # of SVR3 minor device bits */
91 #define	O_MAXMAJ	0x7f	/* SVR3 max major value */
92 #define	O_MAXMIN	0xff	/* SVR3 max minor value */
93 
94 
95 #define	L_BITSMAJOR32	14	/* # of SVR4 major device bits */
96 #define	L_BITSMINOR32	18	/* # of SVR4 minor device bits */
97 #define	L_MAXMAJ32	0x3fff	/* SVR4 max major value */
98 #define	L_MAXMIN32	0x3ffff	/* MAX minor for 3b2 software drivers. */
99 				/* For 3b2 hardware devices the minor is */
100 				/* restricted to 256 (0-255) */
101 
102 #ifdef _LP64
103 #define	L_BITSMAJOR	32	/* # of major device bits in 64-bit Solaris */
104 #define	L_BITSMINOR	32	/* # of minor device bits in 64-bit Solaris */
105 #define	L_MAXMAJ	0xfffffffful	/* max major value */
106 #define	L_MAXMIN	0xfffffffful	/* max minor value */
107 #else
108 #define	L_BITSMAJOR	L_BITSMAJOR32
109 #define	L_BITSMINOR	L_BITSMINOR32
110 #define	L_MAXMAJ	L_MAXMAJ32
111 #define	L_MAXMIN	L_MAXMIN32
112 #endif
113 
114 #ifdef _KERNEL
115 
116 /* major part of a device internal to the kernel */
117 
118 #define	major(x)	(major_t)((((unsigned)(x)) >> O_BITSMINOR) & O_MAXMAJ)
119 #define	bmajor(x)	(major_t)((((unsigned)(x)) >> O_BITSMINOR) & O_MAXMAJ)
120 
121 /* get internal major part of expanded device number */
122 
123 #define	getmajor(x)	(major_t)((((dev_t)(x)) >> L_BITSMINOR) & L_MAXMAJ)
124 
125 /* minor part of a device internal to the kernel */
126 
127 #define	minor(x)	(minor_t)((x) & O_MAXMIN)
128 
129 /* get internal minor part of expanded device number */
130 
131 #define	getminor(x)	(minor_t)((x) & L_MAXMIN)
132 
133 #else
134 
135 /* major part of a device external from the kernel (same as emajor below) */
136 
137 #define	major(x)	(major_t)((((unsigned)(x)) >> O_BITSMINOR) & O_MAXMAJ)
138 
139 /* minor part of a device external from the kernel  (same as eminor below) */
140 
141 #define	minor(x)	(minor_t)((x) & O_MAXMIN)
142 
143 #endif	/* _KERNEL */
144 
145 /* create old device number */
146 
147 #define	makedev(x, y) (unsigned short)(((x) << O_BITSMINOR) | ((y) & O_MAXMIN))
148 
149 /* make an new device number */
150 
151 #define	makedevice(x, y) (dev_t)(((dev_t)(x) << L_BITSMINOR) | ((y) & L_MAXMIN))
152 
153 
154 /*
155  * emajor() allows kernel/driver code to print external major numbers
156  * eminor() allows kernel/driver code to print external minor numbers
157  */
158 
159 #define	emajor(x) \
160 	(major_t)(((unsigned int)(x) >> O_BITSMINOR) > O_MAXMAJ) ? \
161 	    NODEV : (((unsigned int)(x) >> O_BITSMINOR) & O_MAXMAJ)
162 
163 #define	eminor(x) \
164 	(minor_t)((x) & O_MAXMIN)
165 
166 /*
167  * get external major and minor device
168  * components from expanded device number
169  */
170 #define	getemajor(x)	(major_t)((((dev_t)(x) >> L_BITSMINOR) > L_MAXMAJ) ? \
171 			    NODEV : (((dev_t)(x) >> L_BITSMINOR) & L_MAXMAJ))
172 #define	geteminor(x)	(minor_t)((x) & L_MAXMIN)
173 
174 /*
175  * These are versions of the kernel routines for compressing and
176  * expanding long device numbers that don't return errors.
177  */
178 #if (L_BITSMAJOR32 == L_BITSMAJOR) && (L_BITSMINOR32 == L_BITSMINOR)
179 
180 #define	DEVCMPL(x)	(x)
181 #define	DEVEXPL(x)	(x)
182 
183 #else
184 
185 #define	DEVCMPL(x)	\
186 	(dev32_t)((((x) >> L_BITSMINOR) > L_MAXMAJ32 || \
187 	    ((x) & L_MAXMIN) > L_MAXMIN32) ? NODEV32 : \
188 	    ((((x) >> L_BITSMINOR) << L_BITSMINOR32) | ((x) & L_MAXMIN32)))
189 
190 #define	DEVEXPL(x)	\
191 	(((x) == NODEV32) ? NODEV : \
192 	makedevice(((x) >> L_BITSMINOR32) & L_MAXMAJ32, (x) & L_MAXMIN32))
193 
194 #endif /* L_BITSMAJOR32 ... */
195 
196 /* convert to old (SVR3.2) dev format */
197 
198 #define	cmpdev(x) \
199 	(o_dev_t)((((x) >> L_BITSMINOR) > O_MAXMAJ || \
200 	    ((x) & L_MAXMIN) > O_MAXMIN) ? NODEV : \
201 	    ((((x) >> L_BITSMINOR) << O_BITSMINOR) | ((x) & O_MAXMIN)))
202 
203 /* convert to new (SVR4) dev format */
204 
205 #define	expdev(x) \
206 	(dev_t)(((dev_t)(((x) >> O_BITSMINOR) & O_MAXMAJ) << L_BITSMINOR) | \
207 	    ((x) & O_MAXMIN))
208 
209 /*
210  * Macro for checking power of 2 address alignment.
211  */
212 #define	IS_P2ALIGNED(v, a) ((((uintptr_t)(v)) & ((uintptr_t)(a) - 1)) == 0)
213 
214 /*
215  * Macros for counting and rounding.
216  */
217 #define	howmany(x, y)	(((x)+((y)-1))/(y))
218 #define	roundup(x, y)	((((x)+((y)-1))/(y))*(y))
219 
220 /*
221  * Macro to determine if value is a power of 2
222  */
223 #define	ISP2(x)		(((x) & ((x) - 1)) == 0)
224 
225 /*
226  * Macros for various sorts of alignment and rounding when the alignment
227  * is known to be a power of 2.
228  */
229 #define	P2ALIGN(x, align)		((x) & -(align))
230 #define	P2PHASE(x, align)		((x) & ((align) - 1))
231 #define	P2NPHASE(x, align)		(-(x) & ((align) - 1))
232 #define	P2ROUNDUP(x, align)		(-(-(x) & -(align)))
233 #define	P2END(x, align)			(-(~(x) & -(align)))
234 #define	P2PHASEUP(x, align, phase)	((phase) - (((phase) - (x)) & -(align)))
235 #define	P2CROSS(x, y, align)		(((x) ^ (y)) > (align) - 1)
236 /*
237  * Determine whether two numbers have the same high-order bit.
238  */
239 #define	P2SAMEHIGHBIT(x, y)		(((x) ^ (y)) < ((x) & (y)))
240 
241 /*
242  * Typed version of the P2* macros.  These macros should be used to ensure
243  * that the result is correctly calculated based on the data type of (x),
244  * which is passed in as the last argument, regardless of the data
245  * type of the alignment.  For example, if (x) is of type uint64_t,
246  * and we want to round it up to a page boundary using "PAGESIZE" as
247  * the alignment, we can do either
248  *	P2ROUNDUP(x, (uint64_t)PAGESIZE)
249  * or
250  *	P2ROUNDUP_TYPED(x, PAGESIZE, uint64_t)
251  */
252 #define	P2ALIGN_TYPED(x, align, type)	\
253 	((type)(x) & -(type)(align))
254 #define	P2PHASE_TYPED(x, align, type)	\
255 	((type)(x) & ((type)(align) - 1))
256 #define	P2NPHASE_TYPED(x, align, type)	\
257 	(-(type)(x) & ((type)(align) - 1))
258 #define	P2ROUNDUP_TYPED(x, align, type)	\
259 	(-(-(type)(x) & -(type)(align)))
260 #define	P2END_TYPED(x, align, type)	\
261 	(-(~(type)(x) & -(type)(align)))
262 #define	P2PHASEUP_TYPED(x, align, phase, type)	\
263 	((type)(phase) - (((type)(phase) - (type)(x)) & -(type)(align)))
264 #define	P2CROSS_TYPED(x, y, align, type)	\
265 	(((type)(x) ^ (type)(y)) > (type)(align) - 1)
266 #define	P2SAMEHIGHBIT_TYPED(x, y, type) \
267 	(((type)(x) ^ (type)(y)) < ((type)(x) & (type)(y)))
268 
269 /*
270  * Macros to atomically increment/decrement a variable.  mutex and var
271  * must be pointers.
272  */
273 #define	INCR_COUNT(var, mutex) mutex_enter(mutex), (*(var))++, mutex_exit(mutex)
274 #define	DECR_COUNT(var, mutex) mutex_enter(mutex), (*(var))--, mutex_exit(mutex)
275 
276 #if defined(_KERNEL) && !defined(_KMEMUSER) && !defined(offsetof)
277 
278 /* avoid any possibility of clashing with <stddef.h> version */
279 
280 #define	offsetof(s, m)	((size_t)(&(((s *)0)->m)))
281 #endif
282 
283 #ifdef	__cplusplus
284 }
285 #endif
286 
287 #endif	/* _SYS_SYSMACROS_H */
288