include/sys/sysmacros.h

   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  * Copyright 2018 Joyent Inc.
  32  */
  33
  34 #ifndef _SYS_SYSMACROS_H
  35 #define _SYS_SYSMACROS_H
  36
  37 #include <sys/param.h>
  38 #include <sys/stddef.h>
  39
  40 #ifdef  __cplusplus
  41 extern "C" {
  42 #endif
  43
  44 /*
  45  * Some macros for units conversion
  46  */
  47 /*
  48  * Disk blocks (sectors) and bytes.
  49  */
  50 #define dtob(DD)        ((DD) << DEV_BSHIFT)
  51 #define btod(BB)        (((BB) + DEV_BSIZE - 1) >> DEV_BSHIFT)
  52 #define btodt(BB)       ((BB) >> DEV_BSHIFT)
  53 #define lbtod(BB)       (((offset_t)(BB) + DEV_BSIZE - 1) >> DEV_BSHIFT)
  54
  55 /* common macros */
  56 #ifndef MIN
  57 #define MIN(a, b)       ((a) < (b) ? (a) : (b))
  58 #endif
  59 #ifndef MAX
  60 #define MAX(a, b)       ((a) < (b) ? (b) : (a))
  61 #endif
  62 #ifndef ABS
  63 #define ABS(a)          ((a) < 0 ? -(a) : (a))
  64 #endif
  65 #ifndef SIGNOF
  66 #define SIGNOF(a)       ((a) < 0 ? -1 : (a) > 0)
  67 #endif
  68
  69 #ifdef _KERNEL
  70
  71 /*
  72  * Convert a single byte to/from binary-coded decimal (BCD).
  73  */
  74 extern unsigned char byte_to_bcd[256];
  75 extern unsigned char bcd_to_byte[256];
  76
  77 #define BYTE_TO_BCD(x)  byte_to_bcd[(x) & 0xff]
  78 #define BCD_TO_BYTE(x)  bcd_to_byte[(x) & 0xff]
  79
  80 #endif  /* _KERNEL */
  81
  82 /*
  83  * WARNING: The device number macros defined here should not be used by device
  84  * drivers or user software. Device drivers should use the device functions
  85  * defined in the DDI/DKI interface (see also ddi.h). Application software
  86  * should make use of the library routines available in makedev(3C). A set of
  87  * new device macros are provided to operate on the expanded device number
  88  * format supported in SVR4. Macro versions of the DDI device functions are
  89  * provided for use by kernel proper routines only.
  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 /* get internal major part of expanded device number */
 120
 121 #define getmajor(x)     (major_t)((((dev_t)(x)) >> L_BITSMINOR) & L_MAXMAJ)
 122
 123 /* get internal minor part of expanded device number */
 124
 125 #define getminor(x)     (minor_t)((x) & L_MAXMIN)
 126
 127 #endif  /* _KERNEL */
 128
 129 /* make an new device number */
 130
 131 #define makedevice(x, y) (dev_t)(((dev_t)(x) << L_BITSMINOR) | ((y) & L_MAXMIN))
 132
 133 /*
 134  * get external major and minor device
 135  * components from expanded device number
 136  */
 137 #define getemajor(x)    (major_t)((((dev_t)(x) >> L_BITSMINOR) > L_MAXMAJ) ? \
 138                             NODEV : (((dev_t)(x) >> L_BITSMINOR) & L_MAXMAJ))
 139 #define geteminor(x)    (minor_t)((x) & L_MAXMIN)
 140
 141 /*
 142  * These are versions of the kernel routines for compressing and
 143  * expanding long device numbers that don't return errors.
 144  */
 145 #if (L_BITSMAJOR32 == L_BITSMAJOR) && (L_BITSMINOR32 == L_BITSMINOR)
 146
 147 #define DEVCMPL(x)      (x)
 148 #define DEVEXPL(x)      (x)
 149
 150 #else
 151
 152 #define DEVCMPL(x)      \
 153         (dev32_t)((((x) >> L_BITSMINOR) > L_MAXMAJ32 || \
 154             ((x) & L_MAXMIN) > L_MAXMIN32) ? NODEV32 : \
 155             ((((x) >> L_BITSMINOR) << L_BITSMINOR32) | ((x) & L_MAXMIN32)))
 156
 157 #define DEVEXPL(x)      \
 158         (((x) == NODEV32) ? NODEV : \
 159         makedevice(((x) >> L_BITSMINOR32) & L_MAXMAJ32, (x) & L_MAXMIN32))
 160
 161 #endif /* L_BITSMAJOR32 ... */
 162
 163 /* convert to old (SVR3.2) dev format */
 164
 165 #define cmpdev(x) \
 166         (o_dev_t)((((x) >> L_BITSMINOR) > O_MAXMAJ || \
 167             ((x) & L_MAXMIN) > O_MAXMIN) ? NODEV : \
 168             ((((x) >> L_BITSMINOR) << O_BITSMINOR) | ((x) & O_MAXMIN)))
 169
 170 /* convert to new (SVR4) dev format */
 171
 172 #define expdev(x) \
 173         (dev_t)(((dev_t)(((x) >> O_BITSMINOR) & O_MAXMAJ) << L_BITSMINOR) | \
 174             ((x) & O_MAXMIN))
 175
 176 /*
 177  * Macro for checking power of 2 address alignment.
 178  */
 179 #define IS_P2ALIGNED(v, a) ((((uintptr_t)(v)) & ((uintptr_t)(a) - 1)) == 0)
 180
 181 /*
 182  * Macros for counting and rounding.
 183  */
 184 #define howmany(x, y)   (((x)+((y)-1))/(y))
 185 #define roundup(x, y)   ((((x)+((y)-1))/(y))*(y))
 186
 187 /*
 188  * Macro to determine if value is a power of 2
 189  */
 190 #define ISP2(x)         (((x) & ((x) - 1)) == 0)
 191
 192 /*
 193  * Macros for various sorts of alignment and rounding.  The "align" must
 194  * be a power of 2.  Often times it is a block, sector, or page.
 195  */
 196
 197 /*
 198  * return x rounded down to an align boundary
 199  * eg, P2ALIGN(1200, 1024) == 1024 (1*align)
 200  * eg, P2ALIGN(1024, 1024) == 1024 (1*align)
 201  * eg, P2ALIGN(0x1234, 0x100) == 0x1200 (0x12*align)
 202  * eg, P2ALIGN(0x5600, 0x100) == 0x5600 (0x56*align)
 203  */
 204 #define P2ALIGN(x, align)               ((x) & -(align))
 205
 206 /*
 207  * return x % (mod) align
 208  * eg, P2PHASE(0x1234, 0x100) == 0x34 (x-0x12*align)
 209  * eg, P2PHASE(0x5600, 0x100) == 0x00 (x-0x56*align)
 210  */
 211 #define P2PHASE(x, align)               ((x) & ((align) - 1))
 212
 213 /*
 214  * return how much space is left in this block (but if it's perfectly
 215  * aligned, return 0).
 216  * eg, P2NPHASE(0x1234, 0x100) == 0xcc (0x13*align-x)
 217  * eg, P2NPHASE(0x5600, 0x100) == 0x00 (0x56*align-x)
 218  */
 219 #define P2NPHASE(x, align)              (-(x) & ((align) - 1))
 220
 221 /*
 222  * return x rounded up to an align boundary
 223  * eg, P2ROUNDUP(0x1234, 0x100) == 0x1300 (0x13*align)
 224  * eg, P2ROUNDUP(0x5600, 0x100) == 0x5600 (0x56*align)
 225  */
 226 #define P2ROUNDUP(x, align)             (-(-(x) & -(align)))
 227
 228 /*
 229  * return the ending address of the block that x is in
 230  * eg, P2END(0x1234, 0x100) == 0x12ff (0x13*align - 1)
 231  * eg, P2END(0x5600, 0x100) == 0x56ff (0x57*align - 1)
 232  */
 233 #define P2END(x, align)                 (-(~(x) & -(align)))
 234
 235 /*
 236  * return x rounded up to the next phase (offset) within align.
 237  * phase should be < align.
 238  * eg, P2PHASEUP(0x1234, 0x100, 0x10) == 0x1310 (0x13*align + phase)
 239  * eg, P2PHASEUP(0x5600, 0x100, 0x10) == 0x5610 (0x56*align + phase)
 240  */
 241 #define P2PHASEUP(x, align, phase)      ((phase) - (((phase) - (x)) & -(align)))
 242
 243 /*
 244  * return TRUE if adding len to off would cause it to cross an align
 245  * boundary.
 246  * eg, P2BOUNDARY(0x1234, 0xe0, 0x100) == TRUE (0x1234 + 0xe0 == 0x1314)
 247  * eg, P2BOUNDARY(0x1234, 0x50, 0x100) == FALSE (0x1234 + 0x50 == 0x1284)
 248  */
 249 #define P2BOUNDARY(off, len, align) \
 250         (((off) ^ ((off) + (len) - 1)) > (align) - 1)
 251
 252 /*
 253  * Return TRUE if they have the same highest bit set.
 254  * eg, P2SAMEHIGHBIT(0x1234, 0x1001) == TRUE (the high bit is 0x1000)
 255  * eg, P2SAMEHIGHBIT(0x1234, 0x3010) == FALSE (high bit of 0x3010 is 0x2000)
 256  */
 257 #define P2SAMEHIGHBIT(x, y)             (((x) ^ (y)) < ((x) & (y)))
 258
 259 /*
 260  * Typed version of the P2* macros.  These macros should be used to ensure
 261  * that the result is correctly calculated based on the data type of (x),
 262  * which is passed in as the last argument, regardless of the data
 263  * type of the alignment.  For example, if (x) is of type uint64_t,
 264  * and we want to round it up to a page boundary using "PAGESIZE" as
 265  * the alignment, we can do either
 266  *      P2ROUNDUP(x, (uint64_t)PAGESIZE)
 267  * or
 268  *      P2ROUNDUP_TYPED(x, PAGESIZE, uint64_t)
 269  */
 270 #define P2ALIGN_TYPED(x, align, type)   \
 271         ((type)(x) & -(type)(align))
 272 #define P2PHASE_TYPED(x, align, type)   \
 273         ((type)(x) & ((type)(align) - 1))
 274 #define P2NPHASE_TYPED(x, align, type)  \
 275         (-(type)(x) & ((type)(align) - 1))
 276 #define P2ROUNDUP_TYPED(x, align, type) \
 277         (-(-(type)(x) & -(type)(align)))
 278 #define P2END_TYPED(x, align, type)     \
 279         (-(~(type)(x) & -(type)(align)))
 280 #define P2PHASEUP_TYPED(x, align, phase, type)  \
 281         ((type)(phase) - (((type)(phase) - (type)(x)) & -(type)(align)))
 282 #define P2CROSS_TYPED(x, y, align, type)        \
 283         (((type)(x) ^ (type)(y)) > (type)(align) - 1)
 284 #define P2SAMEHIGHBIT_TYPED(x, y, type) \
 285         (((type)(x) ^ (type)(y)) < ((type)(x) & (type)(y)))
 286
 287 /*
 288  * Macros to atomically increment/decrement a variable.  mutex and var
 289  * must be pointers.
 290  */
 291 #define INCR_COUNT(var, mutex) mutex_enter(mutex), (*(var))++, mutex_exit(mutex)
 292 #define DECR_COUNT(var, mutex) mutex_enter(mutex), (*(var))--, mutex_exit(mutex)
 293
 294 /*
 295  * Macros to declare bitfields - the order in the parameter list is
 296  * Low to High - that is, declare bit 0 first.  We only support 8-bit bitfields
 297  * because if a field crosses a byte boundary it's not likely to be meaningful
 298  * without reassembly in its nonnative endianness.
 299  */
 300 #if defined(_BIT_FIELDS_LTOH)
 301 #define DECL_BITFIELD2(_a, _b)                          \
 302         uint8_t _a, _b
 303 #define DECL_BITFIELD3(_a, _b, _c)                      \
 304         uint8_t _a, _b, _c
 305 #define DECL_BITFIELD4(_a, _b, _c, _d)                  \
 306         uint8_t _a, _b, _c, _d
 307 #define DECL_BITFIELD5(_a, _b, _c, _d, _e)              \
 308         uint8_t _a, _b, _c, _d, _e
 309 #define DECL_BITFIELD6(_a, _b, _c, _d, _e, _f)          \
 310         uint8_t _a, _b, _c, _d, _e, _f
 311 #define DECL_BITFIELD7(_a, _b, _c, _d, _e, _f, _g)      \
 312         uint8_t _a, _b, _c, _d, _e, _f, _g
 313 #define DECL_BITFIELD8(_a, _b, _c, _d, _e, _f, _g, _h)  \
 314         uint8_t _a, _b, _c, _d, _e, _f, _g, _h
 315 #elif defined(_BIT_FIELDS_HTOL)
 316 #define DECL_BITFIELD2(_a, _b)                          \
 317         uint8_t _b, _a
 318 #define DECL_BITFIELD3(_a, _b, _c)                      \
 319         uint8_t _c, _b, _a
 320 #define DECL_BITFIELD4(_a, _b, _c, _d)                  \
 321         uint8_t _d, _c, _b, _a
 322 #define DECL_BITFIELD5(_a, _b, _c, _d, _e)              \
 323         uint8_t _e, _d, _c, _b, _a
 324 #define DECL_BITFIELD6(_a, _b, _c, _d, _e, _f)          \
 325         uint8_t _f, _e, _d, _c, _b, _a
 326 #define DECL_BITFIELD7(_a, _b, _c, _d, _e, _f, _g)      \
 327         uint8_t _g, _f, _e, _d, _c, _b, _a
 328 #define DECL_BITFIELD8(_a, _b, _c, _d, _e, _f, _g, _h)  \
 329         uint8_t _h, _g, _f, _e, _d, _c, _b, _a
 330 #else
 331 #error  One of _BIT_FIELDS_LTOH or _BIT_FIELDS_HTOL must be defined
 332 #endif  /* _BIT_FIELDS_LTOH */
 333
 334 #if !defined(ARRAY_SIZE)
 335 #define ARRAY_SIZE(x)   (sizeof (x) / sizeof (x[0]))
 336 #endif
 337
 338 /*
 339  * Add a value to a uint64_t that saturates at UINT64_MAX instead of wrapping
 340  * around.
 341  */
 342 #define UINT64_OVERFLOW_ADD(val, add) \
 343         ((val) > ((val) + (add)) ? (UINT64_MAX) : ((val) + (add)))
 344
 345 /*
 346  * Convert to an int64, saturating at INT64_MAX.
 347  */
 348 #define UINT64_OVERFLOW_TO_INT64(uval) \
 349         (((uval) > INT64_MAX) ? INT64_MAX : (int64_t)(uval))
 350
 351 #ifdef  __cplusplus
 352 }
 353 #endif
 354
 355 #endif  /* _SYS_SYSMACROS_H */