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Masahiro Yamadacba1da42014-11-07 03:03:28 +09001#ifndef _LINUX_KERNEL_H
2#define _LINUX_KERNEL_H
3
4
5#include <linux/types.h>
6
Masahiro Yamada48c7ea32014-11-07 03:03:29 +09007#define USHRT_MAX ((u16)(~0U))
8#define SHRT_MAX ((s16)(USHRT_MAX>>1))
9#define SHRT_MIN ((s16)(-SHRT_MAX - 1))
Masahiro Yamadacba1da42014-11-07 03:03:28 +090010#define INT_MAX ((int)(~0U>>1))
11#define INT_MIN (-INT_MAX - 1)
Masahiro Yamada48c7ea32014-11-07 03:03:29 +090012#define UINT_MAX (~0U)
13#define LONG_MAX ((long)(~0UL>>1))
14#define LONG_MIN (-LONG_MAX - 1)
15#define ULONG_MAX (~0UL)
Masahiro Yamadacba1da42014-11-07 03:03:28 +090016#define LLONG_MAX ((long long)(~0ULL>>1))
Masahiro Yamada48c7ea32014-11-07 03:03:29 +090017#define LLONG_MIN (-LLONG_MAX - 1)
18#define ULLONG_MAX (~0ULL)
Simon Glass803f2eb2014-11-24 21:18:21 -070019#ifndef SIZE_MAX
Masahiro Yamada48c7ea32014-11-07 03:03:29 +090020#define SIZE_MAX (~(size_t)0)
Simon Glass803f2eb2014-11-24 21:18:21 -070021#endif
Masahiro Yamadacba1da42014-11-07 03:03:28 +090022
23#define U8_MAX ((u8)~0U)
Masahiro Yamada48c7ea32014-11-07 03:03:29 +090024#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))
Masahiro Yamadacba1da42014-11-07 03:03:28 +090029#define U32_MAX ((u32)~0U)
Masahiro Yamada48c7ea32014-11-07 03:03:29 +090030#define S32_MAX ((s32)(U32_MAX>>1))
31#define S32_MIN ((s32)(-S32_MAX - 1))
Masahiro Yamadacba1da42014-11-07 03:03:28 +090032#define U64_MAX ((u64)~0ULL)
Masahiro Yamada48c7ea32014-11-07 03:03:29 +090033#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))
Masahiro Yamadacba1da42014-11-07 03:03:28 +090039
40#define ALIGN(x,a) __ALIGN_MASK((x),(typeof(x))(a)-1)
41#define __ALIGN_MASK(x,mask) (((x)+(mask))&~(mask))
Masahiro Yamada48c7ea32014-11-07 03:03:29 +090042#define PTR_ALIGN(p, a) ((typeof(p))ALIGN((unsigned long)(p), (a)))
43#define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0)
Masahiro Yamadacba1da42014-11-07 03:03:28 +090044
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
Masahiro Yamada48c7ea32014-11-07 03:03:29 +090057#define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
Masahiro Yamadacba1da42014-11-07 03:03:28 +090058#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
59
Masahiro Yamada48c7ea32014-11-07 03:03:29 +090060#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
Masahiro Yamada111396c2014-11-07 03:03:30 +090066/* 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)
Masahiro Yamada48c7ea32014-11-07 03:03:29 +090073#define rounddown(x, y) ( \
74{ \
75 typeof(x) __x = (x); \
76 __x - (__x % (y)); \
77} \
78)
79
Masahiro Yamadacba1da42014-11-07 03:03:28 +090080/*
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); \
Masahiro Yamadab4141192014-11-07 03:03:31 +0900155 (void) (&_min1 == &_min2); \
Masahiro Yamadacba1da42014-11-07 03:03:28 +0900156 _min1 < _min2 ? _min1 : _min2; })
157
158#define max(x, y) ({ \
159 typeof(x) _max1 = (x); \
160 typeof(y) _max2 = (y); \
Masahiro Yamadab4141192014-11-07 03:03:31 +0900161 (void) (&_max1 == &_max2); \
Masahiro Yamadacba1da42014-11-07 03:03:28 +0900162 _max1 > _max2 ? _max1 : _max2; })
163
Masahiro Yamadab4141192014-11-07 03:03:31 +0900164#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)
Masahiro Yamadacba1da42014-11-07 03:03:28 +0900166
Masahiro Yamada48c7ea32014-11-07 03:03:29 +0900167/**
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
Masahiro Yamadacba1da42014-11-07 03:03:28 +0900188/*
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/**
Masahiro Yamada48c7ea32014-11-07 03:03:29 +0900205 * 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/**
Masahiro Yamadacba1da42014-11-07 03:03:28 +0900237 * 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