LXR uboot/include/linux/kernel.h

   1#ifndef _LINUX_KERNEL_H
   2#define _LINUX_KERNEL_H
   3
   4
   5#include <linux/types.h>
   6
   7#define USHRT_MAX       ((u16)(~0U))
   8#define SHRT_MAX        ((s16)(USHRT_MAX>>1))
   9#define SHRT_MIN        ((s16)(-SHRT_MAX - 1))
  10#define INT_MAX         ((int)(~0U>>1))
  11#define INT_MIN         (-INT_MAX - 1)
  12#define UINT_MAX        (~0U)
  13#define LONG_MAX        ((long)(~0UL>>1))
  14#define LONG_MIN        (-LONG_MAX - 1)
  15#define ULONG_MAX       (~0UL)
  16#define LLONG_MAX       ((long long)(~0ULL>>1))
  17#define LLONG_MIN       (-LLONG_MAX - 1)
  18#define ULLONG_MAX      (~0ULL)
  19#ifndef SIZE_MAX
  20#define SIZE_MAX        (~(size_t)0)
  21#endif
  22
  23#define U8_MAX          ((u8)~0U)
  24#define S8_MAX          ((s8)(U8_MAX>>1))
  25#define S8_MIN          ((s8)(-S8_MAX - 1))
  26#define U16_MAX         ((u16)~0U)
  27#define S16_MAX         ((s16)(U16_MAX>>1))
  28#define S16_MIN         ((s16)(-S16_MAX - 1))
  29#define U32_MAX         ((u32)~0U)
  30#define S32_MAX         ((s32)(U32_MAX>>1))
  31#define S32_MIN         ((s32)(-S32_MAX - 1))
  32#define U64_MAX         ((u64)~0ULL)
  33#define S64_MAX         ((s64)(U64_MAX>>1))
  34#define S64_MIN         ((s64)(-S64_MAX - 1))
  35
  36#define STACK_MAGIC     0xdeadbeef
  37
  38#define REPEAT_BYTE(x)  ((~0ul / 0xff) * (x))
  39
  40#define ALIGN(x,a)              __ALIGN_MASK((x),(typeof(x))(a)-1)
  41#define __ALIGN_MASK(x,mask)    (((x)+(mask))&~(mask))
  42#define PTR_ALIGN(p, a)         ((typeof(p))ALIGN((unsigned long)(p), (a)))
  43#define IS_ALIGNED(x, a)                (((x) & ((typeof(x))(a) - 1)) == 0)
  44
  45#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
  46
  47/*
  48 * This looks more complex than it should be. But we need to
  49 * get the type for the ~ right in round_down (it needs to be
  50 * as wide as the result!), and we want to evaluate the macro
  51 * arguments just once each.
  52 */
  53#define __round_mask(x, y) ((__typeof__(x))((y)-1))
  54#define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1)
  55#define round_down(x, y) ((x) & ~__round_mask(x, y))
  56
  57#define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
  58#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
  59
  60#if BITS_PER_LONG == 32
  61# define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP_ULL(ll, d)
  62#else
  63# define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP(ll,d)
  64#endif
  65
  66/* The `const' in roundup() prevents gcc-3.3 from calling __divdi3 */
  67#define roundup(x, y) (                                 \
  68{                                                       \
  69        const typeof(y) __y = y;                        \
  70        (((x) + (__y - 1)) / __y) * __y;                \
  71}                                                       \
  72)
  73#define rounddown(x, y) (                               \
  74{                                                       \
  75        typeof(x) __x = (x);                            \
  76        __x - (__x % (y));                              \
  77}                                                       \
  78)
  79
  80/*
  81 * Divide positive or negative dividend by positive divisor and round
  82 * to closest integer. Result is undefined for negative divisors and
  83 * for negative dividends if the divisor variable type is unsigned.
  84 */
  85#define DIV_ROUND_CLOSEST(x, divisor)(                  \
  86{                                                       \
  87        typeof(x) __x = x;                              \
  88        typeof(divisor) __d = divisor;                  \
  89        (((typeof(x))-1) > 0 ||                         \
  90         ((typeof(divisor))-1) > 0 || (__x) > 0) ?      \
  91                (((__x) + ((__d) / 2)) / (__d)) :       \
  92                (((__x) - ((__d) / 2)) / (__d));        \
  93}                                                       \
  94)
  95
  96/*
  97 * Multiplies an integer by a fraction, while avoiding unnecessary
  98 * overflow or loss of precision.
  99 */
 100#define mult_frac(x, numer, denom)(                     \
 101{                                                       \
 102        typeof(x) quot = (x) / (denom);                 \
 103        typeof(x) rem  = (x) % (denom);                 \
 104        (quot * (numer)) + ((rem * (numer)) / (denom)); \
 105}                                                       \
 106)
 107
 108/**
 109 * upper_32_bits - return bits 32-63 of a number
 110 * @n: the number we're accessing
 111 *
 112 * A basic shift-right of a 64- or 32-bit quantity.  Use this to suppress
 113 * the "right shift count >= width of type" warning when that quantity is
 114 * 32-bits.
 115 */
 116#define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
 117
 118/**
 119 * lower_32_bits - return bits 0-31 of a number
 120 * @n: the number we're accessing
 121 */
 122#define lower_32_bits(n) ((u32)(n))
 123
 124/*
 125 * abs() handles unsigned and signed longs, ints, shorts and chars.  For all
 126 * input types abs() returns a signed long.
 127 * abs() should not be used for 64-bit types (s64, u64, long long) - use abs64()
 128 * for those.
 129 */
 130#define abs(x) ({                                               \
 131                long ret;                                       \
 132                if (sizeof(x) == sizeof(long)) {                \
 133                        long __x = (x);                         \
 134                        ret = (__x < 0) ? -__x : __x;           \
 135                } else {                                        \
 136                        int __x = (x);                          \
 137                        ret = (__x < 0) ? -__x : __x;           \
 138                }                                               \
 139                ret;                                            \
 140        })
 141
 142#define abs64(x) ({                             \
 143                s64 __x = (x);                  \
 144                (__x < 0) ? -__x : __x;         \
 145        })
 146
 147/*
 148 * min()/max()/clamp() macros that also do
 149 * strict type-checking.. See the
 150 * "unnecessary" pointer comparison.
 151 */
 152#define min(x, y) ({                            \
 153        typeof(x) _min1 = (x);                  \
 154        typeof(y) _min2 = (y);                  \
 155        (void) (&_min1 == &_min2);              \
 156        _min1 < _min2 ? _min1 : _min2; })
 157
 158#define max(x, y) ({                            \
 159        typeof(x) _max1 = (x);                  \
 160        typeof(y) _max2 = (y);                  \
 161        (void) (&_max1 == &_max2);              \
 162        _max1 > _max2 ? _max1 : _max2; })
 163
 164#define min3(x, y, z) min((typeof(x))min(x, y), z)
 165#define max3(x, y, z) max((typeof(x))max(x, y), z)
 166
 167/**
 168 * min_not_zero - return the minimum that is _not_ zero, unless both are zero
 169 * @x: value1
 170 * @y: value2
 171 */
 172#define min_not_zero(x, y) ({                   \
 173        typeof(x) __x = (x);                    \
 174        typeof(y) __y = (y);                    \
 175        __x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); })
 176
 177/**
 178 * clamp - return a value clamped to a given range with strict typechecking
 179 * @val: current value
 180 * @lo: lowest allowable value
 181 * @hi: highest allowable value
 182 *
 183 * This macro does strict typechecking of lo/hi to make sure they are of the
 184 * same type as val.  See the unnecessary pointer comparisons.
 185 */
 186#define clamp(val, lo, hi) min((typeof(val))max(val, lo), hi)
 187
 188/*
 189 * ..and if you can't take the strict
 190 * types, you can specify one yourself.
 191 *
 192 * Or not use min/max/clamp at all, of course.
 193 */
 194#define min_t(type, x, y) ({                    \
 195        type __min1 = (x);                      \
 196        type __min2 = (y);                      \
 197        __min1 < __min2 ? __min1: __min2; })
 198
 199#define max_t(type, x, y) ({                    \
 200        type __max1 = (x);                      \
 201        type __max2 = (y);                      \
 202        __max1 > __max2 ? __max1: __max2; })
 203
 204/**
 205 * clamp_t - return a value clamped to a given range using a given type
 206 * @type: the type of variable to use
 207 * @val: current value
 208 * @lo: minimum allowable value
 209 * @hi: maximum allowable value
 210 *
 211 * This macro does no typechecking and uses temporary variables of type
 212 * 'type' to make all the comparisons.
 213 */
 214#define clamp_t(type, val, lo, hi) min_t(type, max_t(type, val, lo), hi)
 215
 216/**
 217 * clamp_val - return a value clamped to a given range using val's type
 218 * @val: current value
 219 * @lo: minimum allowable value
 220 * @hi: maximum allowable value
 221 *
 222 * This macro does no typechecking and uses temporary variables of whatever
 223 * type the input argument 'val' is.  This is useful when val is an unsigned
 224 * type and min and max are literals that will otherwise be assigned a signed
 225 * integer type.
 226 */
 227#define clamp_val(val, lo, hi) clamp_t(typeof(val), val, lo, hi)
 228
 229
 230/*
 231 * swap - swap value of @a and @b
 232 */
 233#define swap(a, b) \
 234        do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
 235
 236/**
 237 * container_of - cast a member of a structure out to the containing structure
 238 * @ptr:        the pointer to the member.
 239 * @type:       the type of the container struct this is embedded in.
 240 * @member:     the name of the member within the struct.
 241 *
 242 */
 243#define container_of(ptr, type, member) ({                      \
 244        const typeof( ((type *)0)->member ) *__mptr = (ptr);    \
 245        (type *)( (char *)__mptr - offsetof(type,member) );})
 246
 247#endif
 248