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(3). 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. Macro routines bmajor(),
  90  * major(), minor(), emajor(), eminor(), and makedev() will be removed or
  91  * their definitions changed at the next major release following SVR4.
  92  */
  93 
  94 #define O_BITSMAJOR     7       /* # of SVR3 major device bits */
  95 #define O_BITSMINOR     8       /* # of SVR3 minor device bits */
  96 #define O_MAXMAJ        0x7f    /* SVR3 max major value */
  97 #define O_MAXMIN        0xff    /* SVR3 max minor value */
  98 
  99 
 100 #define L_BITSMAJOR32   14      /* # of SVR4 major device bits */
 101 #define L_BITSMINOR32   18      /* # of SVR4 minor device bits */
 102 #define L_MAXMAJ32      0x3fff  /* SVR4 max major value */
 103 #define L_MAXMIN32      0x3ffff /* MAX minor for 3b2 software drivers. */
 104                                 /* For 3b2 hardware devices the minor is */
 105                                 /* restricted to 256 (0-255) */
 106 
 107 #ifdef _LP64
 108 #define L_BITSMAJOR     32      /* # of major device bits in 64-bit Solaris */
 109 #define L_BITSMINOR     32      /* # of minor device bits in 64-bit Solaris */
 110 #define L_MAXMAJ        0xfffffffful    /* max major value */
 111 #define L_MAXMIN        0xfffffffful    /* max minor value */
 112 #else
 113 #define L_BITSMAJOR     L_BITSMAJOR32
 114 #define L_BITSMINOR     L_BITSMINOR32
 115 #define L_MAXMAJ        L_MAXMAJ32
 116 #define L_MAXMIN        L_MAXMIN32
 117 #endif
 118 
 119 #ifdef _KERNEL
 120 
 121 /* major part of a device internal to the kernel */
 122 
 123 #define major(x)        (major_t)((((unsigned)(x)) >> O_BITSMINOR) & O_MAXMAJ)
 124 #define bmajor(x)       (major_t)((((unsigned)(x)) >> O_BITSMINOR) & O_MAXMAJ)
 125 
 126 /* get internal major part of expanded device number */
 127 
 128 #define getmajor(x)     (major_t)((((dev_t)(x)) >> L_BITSMINOR) & L_MAXMAJ)
 129 
 130 /* minor part of a device internal to the kernel */
 131 
 132 #define minor(x)        (minor_t)((x) & O_MAXMIN)
 133 
 134 /* get internal minor part of expanded device number */
 135 
 136 #define getminor(x)     (minor_t)((x) & L_MAXMIN)
 137 
 138 #else   /* _KERNEL */
 139 
 140 /* major part of a device external from the kernel (same as emajor below) */
 141 
 142 #define major(x)        (major_t)((((unsigned)(x)) >> O_BITSMINOR) & O_MAXMAJ)
 143 
 144 /* minor part of a device external from the kernel  (same as eminor below) */
 145 
 146 #define minor(x)        (minor_t)((x) & O_MAXMIN)
 147 
 148 #endif  /* _KERNEL */
 149 
 150 /* create old device number */
 151 
 152 #define makedev(x, y) (unsigned short)(((x) << O_BITSMINOR) | ((y) & O_MAXMIN))
 153 
 154 /* make an new device number */
 155 
 156 #define makedevice(x, y) (dev_t)(((dev_t)(x) << L_BITSMINOR) | ((y) & L_MAXMIN))
 157 
 158 
 159 /*
 160  * emajor() allows kernel/driver code to print external major numbers
 161  * eminor() allows kernel/driver code to print external minor numbers
 162  */
 163 
 164 #define emajor(x) \
 165         (major_t)(((unsigned int)(x) >> O_BITSMINOR) > O_MAXMAJ) ? \
 166             NODEV : (((unsigned int)(x) >> O_BITSMINOR) & O_MAXMAJ)
 167 
 168 #define eminor(x) \
 169         (minor_t)((x) & O_MAXMIN)
 170 
 171 /*
 172  * get external major and minor device
 173  * components from expanded device number
 174  */
 175 #define getemajor(x)    (major_t)((((dev_t)(x) >> L_BITSMINOR) > L_MAXMAJ) ? \
 176                             NODEV : (((dev_t)(x) >> L_BITSMINOR) & L_MAXMAJ))
 177 #define geteminor(x)    (minor_t)((x) & L_MAXMIN)
 178 
 179 /*
 180  * These are versions of the kernel routines for compressing and
 181  * expanding long device numbers that don't return errors.
 182  */
 183 #if (L_BITSMAJOR32 == L_BITSMAJOR) && (L_BITSMINOR32 == L_BITSMINOR)
 184 
 185 #define DEVCMPL(x)      (x)
 186 #define DEVEXPL(x)      (x)
 187 
 188 #else
 189 
 190 #define DEVCMPL(x)      \
 191         (dev32_t)((((x) >> L_BITSMINOR) > L_MAXMAJ32 || \
 192             ((x) & L_MAXMIN) > L_MAXMIN32) ? NODEV32 : \
 193             ((((x) >> L_BITSMINOR) << L_BITSMINOR32) | ((x) & L_MAXMIN32)))
 194 
 195 #define DEVEXPL(x)      \
 196         (((x) == NODEV32) ? NODEV : \
 197         makedevice(((x) >> L_BITSMINOR32) & L_MAXMAJ32, (x) & L_MAXMIN32))
 198 
 199 #endif /* L_BITSMAJOR32 ... */
 200 
 201 /* convert to old (SVR3.2) dev format */
 202 
 203 #define cmpdev(x) \
 204         (o_dev_t)((((x) >> L_BITSMINOR) > O_MAXMAJ || \
 205             ((x) & L_MAXMIN) > O_MAXMIN) ? NODEV : \
 206             ((((x) >> L_BITSMINOR) << O_BITSMINOR) | ((x) & O_MAXMIN)))
 207 
 208 /* convert to new (SVR4) dev format */
 209 
 210 #define expdev(x) \
 211         (dev_t)(((dev_t)(((x) >> O_BITSMINOR) & O_MAXMAJ) << L_BITSMINOR) | \
 212             ((x) & O_MAXMIN))
 213 
 214 /*
 215  * Macro for checking power of 2 address alignment.
 216  */
 217 #define IS_P2ALIGNED(v, a) ((((uintptr_t)(v)) & ((uintptr_t)(a) - 1)) == 0)
 218 
 219 /*
 220  * Macros for counting and rounding.
 221  */
 222 #define howmany(x, y)   (((x)+((y)-1))/(y))
 223 #define roundup(x, y)   ((((x)+((y)-1))/(y))*(y))
 224 
 225 /*
 226  * Macro to determine if value is a power of 2
 227  */
 228 #define ISP2(x)         (((x) & ((x) - 1)) == 0)
 229 
 230 /*
 231  * Macros for various sorts of alignment and rounding.  The "align" must
 232  * be a power of 2.  Often times it is a block, sector, or page.
 233  */
 234 
 235 /*
 236  * return x rounded down to an align boundary
 237  * eg, P2ALIGN(1200, 1024) == 1024 (1*align)
 238  * eg, P2ALIGN(1024, 1024) == 1024 (1*align)
 239  * eg, P2ALIGN(0x1234, 0x100) == 0x1200 (0x12*align)
 240  * eg, P2ALIGN(0x5600, 0x100) == 0x5600 (0x56*align)
 241  */
 242 #define P2ALIGN(x, align)               ((x) & -(align))
 243 
 244 /*
 245  * return x % (mod) align
 246  * eg, P2PHASE(0x1234, 0x100) == 0x34 (x-0x12*align)
 247  * eg, P2PHASE(0x5600, 0x100) == 0x00 (x-0x56*align)
 248  */
 249 #define P2PHASE(x, align)               ((x) & ((align) - 1))
 250 
 251 /*
 252  * return how much space is left in this block (but if it's perfectly
 253  * aligned, return 0).
 254  * eg, P2NPHASE(0x1234, 0x100) == 0xcc (0x13*align-x)
 255  * eg, P2NPHASE(0x5600, 0x100) == 0x00 (0x56*align-x)
 256  */
 257 #define P2NPHASE(x, align)              (-(x) & ((align) - 1))
 258 
 259 /*
 260  * return x rounded up to an align boundary
 261  * eg, P2ROUNDUP(0x1234, 0x100) == 0x1300 (0x13*align)
 262  * eg, P2ROUNDUP(0x5600, 0x100) == 0x5600 (0x56*align)
 263  */
 264 #define P2ROUNDUP(x, align)             (-(-(x) & -(align)))
 265 
 266 /*
 267  * return the ending address of the block that x is in
 268  * eg, P2END(0x1234, 0x100) == 0x12ff (0x13*align - 1)
 269  * eg, P2END(0x5600, 0x100) == 0x56ff (0x57*align - 1)
 270  */
 271 #define P2END(x, align)                 (-(~(x) & -(align)))
 272 
 273 /*
 274  * return x rounded up to the next phase (offset) within align.
 275  * phase should be < align.
 276  * eg, P2PHASEUP(0x1234, 0x100, 0x10) == 0x1310 (0x13*align + phase)
 277  * eg, P2PHASEUP(0x5600, 0x100, 0x10) == 0x5610 (0x56*align + phase)
 278  */
 279 #define P2PHASEUP(x, align, phase)      ((phase) - (((phase) - (x)) & -(align)))
 280 
 281 /*
 282  * return TRUE if adding len to off would cause it to cross an align
 283  * boundary.
 284  * eg, P2BOUNDARY(0x1234, 0xe0, 0x100) == TRUE (0x1234 + 0xe0 == 0x1314)
 285  * eg, P2BOUNDARY(0x1234, 0x50, 0x100) == FALSE (0x1234 + 0x50 == 0x1284)
 286  */
 287 #define P2BOUNDARY(off, len, align) \
 288         (((off) ^ ((off) + (len) - 1)) > (align) - 1)
 289 
 290 /*
 291  * Return TRUE if they have the same highest bit set.
 292  * eg, P2SAMEHIGHBIT(0x1234, 0x1001) == TRUE (the high bit is 0x1000)
 293  * eg, P2SAMEHIGHBIT(0x1234, 0x3010) == FALSE (high bit of 0x3010 is 0x2000)
 294  */
 295 #define P2SAMEHIGHBIT(x, y)             (((x) ^ (y)) < ((x) & (y)))
 296 
 297 /*
 298  * Typed version of the P2* macros.  These macros should be used to ensure
 299  * that the result is correctly calculated based on the data type of (x),
 300  * which is passed in as the last argument, regardless of the data
 301  * type of the alignment.  For example, if (x) is of type uint64_t,
 302  * and we want to round it up to a page boundary using "PAGESIZE" as
 303  * the alignment, we can do either
 304  *      P2ROUNDUP(x, (uint64_t)PAGESIZE)
 305  * or
 306  *      P2ROUNDUP_TYPED(x, PAGESIZE, uint64_t)
 307  */
 308 #define P2ALIGN_TYPED(x, align, type)   \
 309         ((type)(x) & -(type)(align))
 310 #define P2PHASE_TYPED(x, align, type)   \
 311         ((type)(x) & ((type)(align) - 1))
 312 #define P2NPHASE_TYPED(x, align, type)  \
 313         (-(type)(x) & ((type)(align) - 1))
 314 #define P2ROUNDUP_TYPED(x, align, type) \
 315         (-(-(type)(x) & -(type)(align)))
 316 #define P2END_TYPED(x, align, type)     \
 317         (-(~(type)(x) & -(type)(align)))
 318 #define P2PHASEUP_TYPED(x, align, phase, type)  \
 319         ((type)(phase) - (((type)(phase) - (type)(x)) & -(type)(align)))
 320 #define P2CROSS_TYPED(x, y, align, type)        \
 321         (((type)(x) ^ (type)(y)) > (type)(align) - 1)
 322 #define P2SAMEHIGHBIT_TYPED(x, y, type) \
 323         (((type)(x) ^ (type)(y)) < ((type)(x) & (type)(y)))
 324 
 325 /*
 326  * Macros to atomically increment/decrement a variable.  mutex and var
 327  * must be pointers.
 328  */
 329 #define INCR_COUNT(var, mutex) mutex_enter(mutex), (*(var))++, mutex_exit(mutex)
 330 #define DECR_COUNT(var, mutex) mutex_enter(mutex), (*(var))--, mutex_exit(mutex)
 331 
 332 /*
 333  * Macros to declare bitfields - the order in the parameter list is
 334  * Low to High - that is, declare bit 0 first.  We only support 8-bit bitfields
 335  * because if a field crosses a byte boundary it's not likely to be meaningful
 336  * without reassembly in its nonnative endianness.
 337  */
 338 #if defined(_BIT_FIELDS_LTOH)
 339 #define DECL_BITFIELD2(_a, _b)                          \
 340         uint8_t _a, _b
 341 #define DECL_BITFIELD3(_a, _b, _c)                      \
 342         uint8_t _a, _b, _c
 343 #define DECL_BITFIELD4(_a, _b, _c, _d)                  \
 344         uint8_t _a, _b, _c, _d
 345 #define DECL_BITFIELD5(_a, _b, _c, _d, _e)              \
 346         uint8_t _a, _b, _c, _d, _e
 347 #define DECL_BITFIELD6(_a, _b, _c, _d, _e, _f)          \
 348         uint8_t _a, _b, _c, _d, _e, _f
 349 #define DECL_BITFIELD7(_a, _b, _c, _d, _e, _f, _g)      \
 350         uint8_t _a, _b, _c, _d, _e, _f, _g
 351 #define DECL_BITFIELD8(_a, _b, _c, _d, _e, _f, _g, _h)  \
 352         uint8_t _a, _b, _c, _d, _e, _f, _g, _h
 353 #elif defined(_BIT_FIELDS_HTOL)
 354 #define DECL_BITFIELD2(_a, _b)                          \
 355         uint8_t _b, _a
 356 #define DECL_BITFIELD3(_a, _b, _c)                      \
 357         uint8_t _c, _b, _a
 358 #define DECL_BITFIELD4(_a, _b, _c, _d)                  \
 359         uint8_t _d, _c, _b, _a
 360 #define DECL_BITFIELD5(_a, _b, _c, _d, _e)              \
 361         uint8_t _e, _d, _c, _b, _a
 362 #define DECL_BITFIELD6(_a, _b, _c, _d, _e, _f)          \
 363         uint8_t _f, _e, _d, _c, _b, _a
 364 #define DECL_BITFIELD7(_a, _b, _c, _d, _e, _f, _g)      \
 365         uint8_t _g, _f, _e, _d, _c, _b, _a
 366 #define DECL_BITFIELD8(_a, _b, _c, _d, _e, _f, _g, _h)  \
 367         uint8_t _h, _g, _f, _e, _d, _c, _b, _a
 368 #else
 369 #error  One of _BIT_FIELDS_LTOH or _BIT_FIELDS_HTOL must be defined
 370 #endif  /* _BIT_FIELDS_LTOH */
 371 
 372 #if !defined(ARRAY_SIZE)
 373 #define ARRAY_SIZE(x)   (sizeof (x) / sizeof (x[0]))
 374 #endif
 375 
 376 /*
 377  * Add a value to a uint64_t that saturates at UINT64_MAX instead of wrapping
 378  * around.
 379  */
 380 #define UINT64_OVERFLOW_ADD(val, add) \
 381         ((val) > ((val) + (add)) ? (UINT64_MAX) : ((val) + (add)))
 382 
 383 /*
 384  * Convert to an int64, saturating at INT64_MAX.
 385  */
 386 #define UINT64_OVERFLOW_TO_INT64(uval) \
 387         (((uval) > INT64_MAX) ? INT64_MAX : (int64_t)(uval))
 388 
 389 #ifdef  __cplusplus
 390 }
 391 #endif
 392 
 393 #endif  /* _SYS_SYSMACROS_H */