1 #ifndef _LINUX_KERNEL_H
2 #define _LINUX_KERNEL_H
3
4 /*
5 * 'kernel.h' contains some often-used function prototypes etc
6 */
7 #define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
8 #define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask))
9
10 #ifdef __KERNEL__
11
12 #include <stdarg.h>
13 #include <linux/linkage.h>
14 #include <linux/stddef.h>
15 #include <linux/types.h>
16 #include <linux/compiler.h>
17 #include <linux/bitops.h>
18 #include <linux/log2.h>
19 #include <linux/typecheck.h>
20 #include <linux/printk.h>
21 #include <linux/dynamic_debug.h>
22 #include <asm/byteorder.h>
23 #include <asm/bug.h>
24
25 #define USHRT_MAX ((u16)(~0U))
26 #define SHRT_MAX ((s16)(USHRT_MAX>>1))
27 #define SHRT_MIN ((s16)(-SHRT_MAX - 1))
28 #define INT_MAX ((int)(~0U>>1))
29 #define INT_MIN (-INT_MAX - 1)
30 #define UINT_MAX (~0U)
31 #define LONG_MAX ((long)(~0UL>>1))
32 #define LONG_MIN (-LONG_MAX - 1)
33 #define ULONG_MAX (~0UL)
34 #define LLONG_MAX ((long long)(~0ULL>>1))
35 #define LLONG_MIN (-LLONG_MAX - 1)
36 #define ULLONG_MAX (~0ULL)
37
38 #define STACK_MAGIC 0xdeadbeef
39
40 #define ALIGN(x, a) __ALIGN_KERNEL((x), (a))
41 #define __ALIGN_MASK(x, mask) __ALIGN_KERNEL_MASK((x), (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(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
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 #define DIV_ROUND_UP_ULL(ll,d) \
60 ({ unsigned long long _tmp = (ll)+(d)-1; do_div(_tmp, d); _tmp; })
61
62 #if BITS_PER_LONG == 32
63 # define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP_ULL(ll, d)
64 #else
65 # define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP(ll,d)
66 #endif
67
68 /* The `const' in roundup() prevents gcc-3.3 from calling __divdi3 */
69 #define roundup(x, y) ( \
70 { \
71 const typeof(y) __y = y; \
72 (((x) + (__y - 1)) / __y) * __y; \
73 } \
74 )
75 #define rounddown(x, y) ( \
76 { \
77 typeof(x) __x = (x); \
78 __x - (__x % (y)); \
79 } \
80 )
81 #define DIV_ROUND_CLOSEST(x, divisor)( \
82 { \
83 typeof(divisor) __divisor = divisor; \
84 (((x) + ((__divisor) / 2)) / (__divisor)); \
85 } \
86 )
87
88 #define _RET_IP_ (unsigned long)__builtin_return_address(0)
89 #define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; })
90
91 #ifdef CONFIG_LBDAF
92 # include <asm/div64.h>
93 # define sector_div(a, b) do_div(a, b)
94 #else
95 # define sector_div(n, b)( \
96 { \
97 int _res; \
98 _res = (n) % (b); \
99 (n) /= (b); \
100 _res; \
101 } \
102 )
103 #endif
104
105 /**
106 * upper_32_bits - return bits 32-63 of a number
107 * @n: the number we're accessing
108 *
109 * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress
110 * the "right shift count >= width of type" warning when that quantity is
111 * 32-bits.
112 */
113 #define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
114
115 /**
116 * lower_32_bits - return bits 0-31 of a number
117 * @n: the number we're accessing
118 */
119 #define lower_32_bits(n) ((u32)(n))
120
121 struct completion;
122 struct pt_regs;
123 struct user;
124
125 #ifdef CONFIG_PREEMPT_VOLUNTARY
126 extern int _cond_resched(void);
127 # define might_resched() _cond_resched()
128 #else
129 # define might_resched() do { } while (0)
130 #endif
131
132 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
133 void __might_sleep(const char *file, int line, int preempt_offset);
134 /**
135 * might_sleep - annotation for functions that can sleep
136 *
137 * this macro will print a stack trace if it is executed in an atomic
138 * context (spinlock, irq-handler, ...).
139 *
140 * This is a useful debugging help to be able to catch problems early and not
141 * be bitten later when the calling function happens to sleep when it is not
142 * supposed to.
143 */
144 # define might_sleep() \
145 do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
146 #else
__might_sleep(const char * file,int line,int preempt_offset)147 static inline void __might_sleep(const char *file, int line,
148 int preempt_offset) { }
149 # define might_sleep() do { might_resched(); } while (0)
150 #endif
151
152 #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
153
154 /*
155 * abs() handles unsigned and signed longs, ints, shorts and chars. For all
156 * input types abs() returns a signed long.
157 * abs() should not be used for 64-bit types (s64, u64, long long) - use abs64()
158 * for those.
159 */
160 #define abs(x) ({ \
161 long ret; \
162 if (sizeof(x) == sizeof(long)) { \
163 long __x = (x); \
164 ret = (__x < 0) ? -__x : __x; \
165 } else { \
166 int __x = (x); \
167 ret = (__x < 0) ? -__x : __x; \
168 } \
169 ret; \
170 })
171
172 #define abs64(x) ({ \
173 s64 __x = (x); \
174 (__x < 0) ? -__x : __x; \
175 })
176
177 #ifdef CONFIG_PROVE_LOCKING
178 void might_fault(void);
179 #else
might_fault(void)180 static inline void might_fault(void)
181 {
182 might_sleep();
183 }
184 #endif
185
186 extern struct atomic_notifier_head panic_notifier_list;
187 extern long (*panic_blink)(int state);
188 __printf(1, 2)
189 void panic(const char *fmt, ...)
190 __noreturn __cold;
191 extern void oops_enter(void);
192 extern void oops_exit(void);
193 void print_oops_end_marker(void);
194 extern int oops_may_print(void);
195 void do_exit(long error_code)
196 __noreturn;
197 void complete_and_exit(struct completion *, long)
198 __noreturn;
199
200 /* Internal, do not use. */
201 int __must_check _kstrtoul(const char *s, unsigned int base, unsigned long *res);
202 int __must_check _kstrtol(const char *s, unsigned int base, long *res);
203
204 int __must_check kstrtoull(const char *s, unsigned int base, unsigned long long *res);
205 int __must_check kstrtoll(const char *s, unsigned int base, long long *res);
kstrtoul(const char * s,unsigned int base,unsigned long * res)206 static inline int __must_check kstrtoul(const char *s, unsigned int base, unsigned long *res)
207 {
208 /*
209 * We want to shortcut function call, but
210 * __builtin_types_compatible_p(unsigned long, unsigned long long) = 0.
211 */
212 if (sizeof(unsigned long) == sizeof(unsigned long long) &&
213 __alignof__(unsigned long) == __alignof__(unsigned long long))
214 return kstrtoull(s, base, (unsigned long long *)res);
215 else
216 return _kstrtoul(s, base, res);
217 }
218
kstrtol(const char * s,unsigned int base,long * res)219 static inline int __must_check kstrtol(const char *s, unsigned int base, long *res)
220 {
221 /*
222 * We want to shortcut function call, but
223 * __builtin_types_compatible_p(long, long long) = 0.
224 */
225 if (sizeof(long) == sizeof(long long) &&
226 __alignof__(long) == __alignof__(long long))
227 return kstrtoll(s, base, (long long *)res);
228 else
229 return _kstrtol(s, base, res);
230 }
231
232 int __must_check kstrtouint(const char *s, unsigned int base, unsigned int *res);
233 int __must_check kstrtoint(const char *s, unsigned int base, int *res);
234
kstrtou64(const char * s,unsigned int base,u64 * res)235 static inline int __must_check kstrtou64(const char *s, unsigned int base, u64 *res)
236 {
237 return kstrtoull(s, base, res);
238 }
239
kstrtos64(const char * s,unsigned int base,s64 * res)240 static inline int __must_check kstrtos64(const char *s, unsigned int base, s64 *res)
241 {
242 return kstrtoll(s, base, res);
243 }
244
kstrtou32(const char * s,unsigned int base,u32 * res)245 static inline int __must_check kstrtou32(const char *s, unsigned int base, u32 *res)
246 {
247 return kstrtouint(s, base, res);
248 }
249
kstrtos32(const char * s,unsigned int base,s32 * res)250 static inline int __must_check kstrtos32(const char *s, unsigned int base, s32 *res)
251 {
252 return kstrtoint(s, base, res);
253 }
254
255 int __must_check kstrtou16(const char *s, unsigned int base, u16 *res);
256 int __must_check kstrtos16(const char *s, unsigned int base, s16 *res);
257 int __must_check kstrtou8(const char *s, unsigned int base, u8 *res);
258 int __must_check kstrtos8(const char *s, unsigned int base, s8 *res);
259
260 int __must_check kstrtoull_from_user(const char __user *s, size_t count, unsigned int base, unsigned long long *res);
261 int __must_check kstrtoll_from_user(const char __user *s, size_t count, unsigned int base, long long *res);
262 int __must_check kstrtoul_from_user(const char __user *s, size_t count, unsigned int base, unsigned long *res);
263 int __must_check kstrtol_from_user(const char __user *s, size_t count, unsigned int base, long *res);
264 int __must_check kstrtouint_from_user(const char __user *s, size_t count, unsigned int base, unsigned int *res);
265 int __must_check kstrtoint_from_user(const char __user *s, size_t count, unsigned int base, int *res);
266 int __must_check kstrtou16_from_user(const char __user *s, size_t count, unsigned int base, u16 *res);
267 int __must_check kstrtos16_from_user(const char __user *s, size_t count, unsigned int base, s16 *res);
268 int __must_check kstrtou8_from_user(const char __user *s, size_t count, unsigned int base, u8 *res);
269 int __must_check kstrtos8_from_user(const char __user *s, size_t count, unsigned int base, s8 *res);
270
kstrtou64_from_user(const char __user * s,size_t count,unsigned int base,u64 * res)271 static inline int __must_check kstrtou64_from_user(const char __user *s, size_t count, unsigned int base, u64 *res)
272 {
273 return kstrtoull_from_user(s, count, base, res);
274 }
275
kstrtos64_from_user(const char __user * s,size_t count,unsigned int base,s64 * res)276 static inline int __must_check kstrtos64_from_user(const char __user *s, size_t count, unsigned int base, s64 *res)
277 {
278 return kstrtoll_from_user(s, count, base, res);
279 }
280
kstrtou32_from_user(const char __user * s,size_t count,unsigned int base,u32 * res)281 static inline int __must_check kstrtou32_from_user(const char __user *s, size_t count, unsigned int base, u32 *res)
282 {
283 return kstrtouint_from_user(s, count, base, res);
284 }
285
kstrtos32_from_user(const char __user * s,size_t count,unsigned int base,s32 * res)286 static inline int __must_check kstrtos32_from_user(const char __user *s, size_t count, unsigned int base, s32 *res)
287 {
288 return kstrtoint_from_user(s, count, base, res);
289 }
290
291 /* Obsolete, do not use. Use kstrto<foo> instead */
292
293 extern unsigned long simple_strtoul(const char *,char **,unsigned int);
294 extern long simple_strtol(const char *,char **,unsigned int);
295 extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
296 extern long long simple_strtoll(const char *,char **,unsigned int);
297 #define strict_strtoul kstrtoul
298 #define strict_strtol kstrtol
299 #define strict_strtoull kstrtoull
300 #define strict_strtoll kstrtoll
301
302 /* lib/printf utilities */
303
304 extern __printf(2, 3) int sprintf(char *buf, const char * fmt, ...);
305 extern __printf(2, 0) int vsprintf(char *buf, const char *, va_list);
306 extern __printf(3, 4)
307 int snprintf(char *buf, size_t size, const char *fmt, ...);
308 extern __printf(3, 0)
309 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args);
310 extern __printf(3, 4)
311 int scnprintf(char *buf, size_t size, const char *fmt, ...);
312 extern __printf(3, 0)
313 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args);
314 extern __printf(2, 3)
315 char *kasprintf(gfp_t gfp, const char *fmt, ...);
316 extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args);
317
318 extern int sscanf(const char *, const char *, ...)
319 __attribute__ ((format (scanf, 2, 3)));
320 extern int vsscanf(const char *, const char *, va_list)
321 __attribute__ ((format (scanf, 2, 0)));
322
323 extern int get_option(char **str, int *pint);
324 extern char *get_options(const char *str, int nints, int *ints);
325 extern unsigned long long memparse(const char *ptr, char **retptr);
326
327 extern int core_kernel_text(unsigned long addr);
328 extern int core_kernel_data(unsigned long addr);
329 extern int __kernel_text_address(unsigned long addr);
330 extern int kernel_text_address(unsigned long addr);
331 extern int func_ptr_is_kernel_text(void *ptr);
332
333 struct pid;
334 extern struct pid *session_of_pgrp(struct pid *pgrp);
335
336 unsigned long int_sqrt(unsigned long);
337
338 extern void bust_spinlocks(int yes);
339 extern void wake_up_klogd(void);
340 extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */
341 extern int panic_timeout;
342 extern int panic_on_oops;
343 extern int panic_on_unrecovered_nmi;
344 extern int panic_on_io_nmi;
345 extern int sysctl_panic_on_stackoverflow;
346 extern const char *print_tainted(void);
347 extern void add_taint(unsigned flag);
348 extern int test_taint(unsigned flag);
349 extern unsigned long get_taint(void);
350 extern int root_mountflags;
351
352 extern bool early_boot_irqs_disabled;
353
354 /* Values used for system_state */
355 extern enum system_states {
356 SYSTEM_BOOTING,
357 SYSTEM_RUNNING,
358 SYSTEM_HALT,
359 SYSTEM_POWER_OFF,
360 SYSTEM_RESTART,
361 SYSTEM_SUSPEND_DISK,
362 } system_state;
363
364 #define TAINT_PROPRIETARY_MODULE 0
365 #define TAINT_FORCED_MODULE 1
366 #define TAINT_UNSAFE_SMP 2
367 #define TAINT_FORCED_RMMOD 3
368 #define TAINT_MACHINE_CHECK 4
369 #define TAINT_BAD_PAGE 5
370 #define TAINT_USER 6
371 #define TAINT_DIE 7
372 #define TAINT_OVERRIDDEN_ACPI_TABLE 8
373 #define TAINT_WARN 9
374 #define TAINT_CRAP 10
375 #define TAINT_FIRMWARE_WORKAROUND 11
376 #define TAINT_OOT_MODULE 12
377
378 extern const char hex_asc[];
379 #define hex_asc_lo(x) hex_asc[((x) & 0x0f)]
380 #define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4]
381
hex_byte_pack(char * buf,u8 byte)382 static inline char *hex_byte_pack(char *buf, u8 byte)
383 {
384 *buf++ = hex_asc_hi(byte);
385 *buf++ = hex_asc_lo(byte);
386 return buf;
387 }
388
pack_hex_byte(char * buf,u8 byte)389 static inline char * __deprecated pack_hex_byte(char *buf, u8 byte)
390 {
391 return hex_byte_pack(buf, byte);
392 }
393
394 extern int hex_to_bin(char ch);
395 extern int __must_check hex2bin(u8 *dst, const char *src, size_t count);
396
397 /*
398 * General tracing related utility functions - trace_printk(),
399 * tracing_on/tracing_off and tracing_start()/tracing_stop
400 *
401 * Use tracing_on/tracing_off when you want to quickly turn on or off
402 * tracing. It simply enables or disables the recording of the trace events.
403 * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
404 * file, which gives a means for the kernel and userspace to interact.
405 * Place a tracing_off() in the kernel where you want tracing to end.
406 * From user space, examine the trace, and then echo 1 > tracing_on
407 * to continue tracing.
408 *
409 * tracing_stop/tracing_start has slightly more overhead. It is used
410 * by things like suspend to ram where disabling the recording of the
411 * trace is not enough, but tracing must actually stop because things
412 * like calling smp_processor_id() may crash the system.
413 *
414 * Most likely, you want to use tracing_on/tracing_off.
415 */
416 #ifdef CONFIG_RING_BUFFER
417 void tracing_on(void);
418 void tracing_off(void);
419 /* trace_off_permanent stops recording with no way to bring it back */
420 void tracing_off_permanent(void);
421 int tracing_is_on(void);
422 #else
tracing_on(void)423 static inline void tracing_on(void) { }
tracing_off(void)424 static inline void tracing_off(void) { }
tracing_off_permanent(void)425 static inline void tracing_off_permanent(void) { }
tracing_is_on(void)426 static inline int tracing_is_on(void) { return 0; }
427 #endif
428
429 enum ftrace_dump_mode {
430 DUMP_NONE,
431 DUMP_ALL,
432 DUMP_ORIG,
433 };
434
435 #ifdef CONFIG_TRACING
436 extern void tracing_start(void);
437 extern void tracing_stop(void);
438 extern void ftrace_off_permanent(void);
439
440 static inline __printf(1, 2)
____trace_printk_check_format(const char * fmt,...)441 void ____trace_printk_check_format(const char *fmt, ...)
442 {
443 }
444 #define __trace_printk_check_format(fmt, args...) \
445 do { \
446 if (0) \
447 ____trace_printk_check_format(fmt, ##args); \
448 } while (0)
449
450 /**
451 * trace_printk - printf formatting in the ftrace buffer
452 * @fmt: the printf format for printing
453 *
454 * Note: __trace_printk is an internal function for trace_printk and
455 * the @ip is passed in via the trace_printk macro.
456 *
457 * This function allows a kernel developer to debug fast path sections
458 * that printk is not appropriate for. By scattering in various
459 * printk like tracing in the code, a developer can quickly see
460 * where problems are occurring.
461 *
462 * This is intended as a debugging tool for the developer only.
463 * Please refrain from leaving trace_printks scattered around in
464 * your code.
465 */
466
467 #define trace_printk(fmt, args...) \
468 do { \
469 __trace_printk_check_format(fmt, ##args); \
470 if (__builtin_constant_p(fmt)) { \
471 static const char *trace_printk_fmt \
472 __attribute__((section("__trace_printk_fmt"))) = \
473 __builtin_constant_p(fmt) ? fmt : NULL; \
474 \
475 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \
476 } else \
477 __trace_printk(_THIS_IP_, fmt, ##args); \
478 } while (0)
479
480 extern __printf(2, 3)
481 int __trace_bprintk(unsigned long ip, const char *fmt, ...);
482
483 extern __printf(2, 3)
484 int __trace_printk(unsigned long ip, const char *fmt, ...);
485
486 extern void trace_dump_stack(void);
487
488 /*
489 * The double __builtin_constant_p is because gcc will give us an error
490 * if we try to allocate the static variable to fmt if it is not a
491 * constant. Even with the outer if statement.
492 */
493 #define ftrace_vprintk(fmt, vargs) \
494 do { \
495 if (__builtin_constant_p(fmt)) { \
496 static const char *trace_printk_fmt \
497 __attribute__((section("__trace_printk_fmt"))) = \
498 __builtin_constant_p(fmt) ? fmt : NULL; \
499 \
500 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \
501 } else \
502 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \
503 } while (0)
504
505 extern int
506 __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap);
507
508 extern int
509 __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap);
510
511 extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode);
512 #else
513 static inline __printf(1, 2)
514 int trace_printk(const char *fmt, ...);
515
tracing_start(void)516 static inline void tracing_start(void) { }
tracing_stop(void)517 static inline void tracing_stop(void) { }
ftrace_off_permanent(void)518 static inline void ftrace_off_permanent(void) { }
trace_dump_stack(void)519 static inline void trace_dump_stack(void) { }
520 static inline int
trace_printk(const char * fmt,...)521 trace_printk(const char *fmt, ...)
522 {
523 return 0;
524 }
525 static inline int
ftrace_vprintk(const char * fmt,va_list ap)526 ftrace_vprintk(const char *fmt, va_list ap)
527 {
528 return 0;
529 }
ftrace_dump(enum ftrace_dump_mode oops_dump_mode)530 static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
531 #endif /* CONFIG_TRACING */
532
533 /*
534 * min()/max()/clamp() macros that also do
535 * strict type-checking.. See the
536 * "unnecessary" pointer comparison.
537 */
538 #define min(x, y) ({ \
539 typeof(x) _min1 = (x); \
540 typeof(y) _min2 = (y); \
541 (void) (&_min1 == &_min2); \
542 _min1 < _min2 ? _min1 : _min2; })
543
544 #define max(x, y) ({ \
545 typeof(x) _max1 = (x); \
546 typeof(y) _max2 = (y); \
547 (void) (&_max1 == &_max2); \
548 _max1 > _max2 ? _max1 : _max2; })
549
550 #define min3(x, y, z) ({ \
551 typeof(x) _min1 = (x); \
552 typeof(y) _min2 = (y); \
553 typeof(z) _min3 = (z); \
554 (void) (&_min1 == &_min2); \
555 (void) (&_min1 == &_min3); \
556 _min1 < _min2 ? (_min1 < _min3 ? _min1 : _min3) : \
557 (_min2 < _min3 ? _min2 : _min3); })
558
559 #define max3(x, y, z) ({ \
560 typeof(x) _max1 = (x); \
561 typeof(y) _max2 = (y); \
562 typeof(z) _max3 = (z); \
563 (void) (&_max1 == &_max2); \
564 (void) (&_max1 == &_max3); \
565 _max1 > _max2 ? (_max1 > _max3 ? _max1 : _max3) : \
566 (_max2 > _max3 ? _max2 : _max3); })
567
568 /**
569 * min_not_zero - return the minimum that is _not_ zero, unless both are zero
570 * @x: value1
571 * @y: value2
572 */
573 #define min_not_zero(x, y) ({ \
574 typeof(x) __x = (x); \
575 typeof(y) __y = (y); \
576 __x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); })
577
578 /**
579 * clamp - return a value clamped to a given range with strict typechecking
580 * @val: current value
581 * @min: minimum allowable value
582 * @max: maximum allowable value
583 *
584 * This macro does strict typechecking of min/max to make sure they are of the
585 * same type as val. See the unnecessary pointer comparisons.
586 */
587 #define clamp(val, min, max) ({ \
588 typeof(val) __val = (val); \
589 typeof(min) __min = (min); \
590 typeof(max) __max = (max); \
591 (void) (&__val == &__min); \
592 (void) (&__val == &__max); \
593 __val = __val < __min ? __min: __val; \
594 __val > __max ? __max: __val; })
595
596 /*
597 * ..and if you can't take the strict
598 * types, you can specify one yourself.
599 *
600 * Or not use min/max/clamp at all, of course.
601 */
602 #define min_t(type, x, y) ({ \
603 type __min1 = (x); \
604 type __min2 = (y); \
605 __min1 < __min2 ? __min1: __min2; })
606
607 #define max_t(type, x, y) ({ \
608 type __max1 = (x); \
609 type __max2 = (y); \
610 __max1 > __max2 ? __max1: __max2; })
611
612 /**
613 * clamp_t - return a value clamped to a given range using a given type
614 * @type: the type of variable to use
615 * @val: current value
616 * @min: minimum allowable value
617 * @max: maximum allowable value
618 *
619 * This macro does no typechecking and uses temporary variables of type
620 * 'type' to make all the comparisons.
621 */
622 #define clamp_t(type, val, min, max) ({ \
623 type __val = (val); \
624 type __min = (min); \
625 type __max = (max); \
626 __val = __val < __min ? __min: __val; \
627 __val > __max ? __max: __val; })
628
629 /**
630 * clamp_val - return a value clamped to a given range using val's type
631 * @val: current value
632 * @min: minimum allowable value
633 * @max: maximum allowable value
634 *
635 * This macro does no typechecking and uses temporary variables of whatever
636 * type the input argument 'val' is. This is useful when val is an unsigned
637 * type and min and max are literals that will otherwise be assigned a signed
638 * integer type.
639 */
640 #define clamp_val(val, min, max) ({ \
641 typeof(val) __val = (val); \
642 typeof(val) __min = (min); \
643 typeof(val) __max = (max); \
644 __val = __val < __min ? __min: __val; \
645 __val > __max ? __max: __val; })
646
647
648 /*
649 * swap - swap value of @a and @b
650 */
651 #define swap(a, b) \
652 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
653
654 /**
655 * container_of - cast a member of a structure out to the containing structure
656 * @ptr: the pointer to the member.
657 * @type: the type of the container struct this is embedded in.
658 * @member: the name of the member within the struct.
659 *
660 */
661 #define container_of(ptr, type, member) ({ \
662 const typeof( ((type *)0)->member ) *__mptr = (ptr); \
663 (type *)( (char *)__mptr - offsetof(type,member) );})
664
665 #ifdef __CHECKER__
666 #define BUILD_BUG_ON_NOT_POWER_OF_2(n)
667 #define BUILD_BUG_ON_ZERO(e) (0)
668 #define BUILD_BUG_ON_NULL(e) ((void*)0)
669 #define BUILD_BUG_ON(condition)
670 #define BUILD_BUG() (0)
671 #else /* __CHECKER__ */
672
673 /* Force a compilation error if a constant expression is not a power of 2 */
674 #define BUILD_BUG_ON_NOT_POWER_OF_2(n) \
675 BUILD_BUG_ON((n) == 0 || (((n) & ((n) - 1)) != 0))
676
677 /* Force a compilation error if condition is true, but also produce a
678 result (of value 0 and type size_t), so the expression can be used
679 e.g. in a structure initializer (or where-ever else comma expressions
680 aren't permitted). */
681 #define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
682 #define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))
683
684 /**
685 * BUILD_BUG_ON - break compile if a condition is true.
686 * @condition: the condition which the compiler should know is false.
687 *
688 * If you have some code which relies on certain constants being equal, or
689 * other compile-time-evaluated condition, you should use BUILD_BUG_ON to
690 * detect if someone changes it.
691 *
692 * The implementation uses gcc's reluctance to create a negative array, but
693 * gcc (as of 4.4) only emits that error for obvious cases (eg. not arguments
694 * to inline functions). So as a fallback we use the optimizer; if it can't
695 * prove the condition is false, it will cause a link error on the undefined
696 * "__build_bug_on_failed". This error message can be harder to track down
697 * though, hence the two different methods.
698 */
699 #ifndef __OPTIMIZE__
700 #define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
701 #else
702 extern int __build_bug_on_failed;
703 #define BUILD_BUG_ON(condition) \
704 do { \
705 ((void)sizeof(char[1 - 2*!!(condition)])); \
706 if (condition) __build_bug_on_failed = 1; \
707 } while(0)
708 #endif
709
710 /**
711 * BUILD_BUG - break compile if used.
712 *
713 * If you have some code that you expect the compiler to eliminate at
714 * build time, you should use BUILD_BUG to detect if it is
715 * unexpectedly used.
716 */
717 #define BUILD_BUG() \
718 do { \
719 extern void __build_bug_failed(void) \
720 __linktime_error("BUILD_BUG failed"); \
721 __build_bug_failed(); \
722 } while (0)
723
724 #endif /* __CHECKER__ */
725
726 /* Trap pasters of __FUNCTION__ at compile-time */
727 #define __FUNCTION__ (__func__)
728
729 /* This helps us to avoid #ifdef CONFIG_NUMA */
730 #ifdef CONFIG_NUMA
731 #define NUMA_BUILD 1
732 #else
733 #define NUMA_BUILD 0
734 #endif
735
736 /* This helps us avoid #ifdef CONFIG_COMPACTION */
737 #ifdef CONFIG_COMPACTION
738 #define COMPACTION_BUILD 1
739 #else
740 #define COMPACTION_BUILD 0
741 #endif
742
743 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
744 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
745 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
746 #endif
747
748 struct sysinfo;
749 extern int do_sysinfo(struct sysinfo *info);
750
751 #endif /* __KERNEL__ */
752
753 #define SI_LOAD_SHIFT 16
754 struct sysinfo {
755 long uptime; /* Seconds since boot */
756 unsigned long loads[3]; /* 1, 5, and 15 minute load averages */
757 unsigned long totalram; /* Total usable main memory size */
758 unsigned long freeram; /* Available memory size */
759 unsigned long sharedram; /* Amount of shared memory */
760 unsigned long bufferram; /* Memory used by buffers */
761 unsigned long totalswap; /* Total swap space size */
762 unsigned long freeswap; /* swap space still available */
763 unsigned short procs; /* Number of current processes */
764 unsigned short pad; /* explicit padding for m68k */
765 unsigned long totalhigh; /* Total high memory size */
766 unsigned long freehigh; /* Available high memory size */
767 unsigned int mem_unit; /* Memory unit size in bytes */
768 char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */
769 };
770
771 #endif
772