Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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kernel
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linux
1#ifndef _LINUX_KERNEL_H
2#define _LINUX_KERNEL_H
3
4/*
5 * 'kernel.h' contains some often-used function prototypes etc
6 */
7
8#ifdef __KERNEL__
9
10#include <stdarg.h>
11#include <linux/linkage.h>
12#include <linux/stddef.h>
13#include <linux/types.h>
14#include <linux/compiler.h>
15#include <linux/bitops.h>
16#include <linux/log2.h>
17#include <asm/byteorder.h>
18#include <asm/bug.h>
19
20extern const char linux_banner[];
21extern const char linux_proc_banner[];
22
23#define USHORT_MAX ((u16)(~0U))
24#define SHORT_MAX ((s16)(USHORT_MAX>>1))
25#define SHORT_MIN (-SHORT_MAX - 1)
26#define INT_MAX ((int)(~0U>>1))
27#define INT_MIN (-INT_MAX - 1)
28#define UINT_MAX (~0U)
29#define LONG_MAX ((long)(~0UL>>1))
30#define LONG_MIN (-LONG_MAX - 1)
31#define ULONG_MAX (~0UL)
32#define LLONG_MAX ((long long)(~0ULL>>1))
33#define LLONG_MIN (-LLONG_MAX - 1)
34#define ULLONG_MAX (~0ULL)
35
36#define STACK_MAGIC 0xdeadbeef
37
38#define ALIGN(x,a) __ALIGN_MASK(x,(typeof(x))(a)-1)
39#define __ALIGN_MASK(x,mask) (((x)+(mask))&~(mask))
40#define PTR_ALIGN(p, a) ((typeof(p))ALIGN((unsigned long)(p), (a)))
41#define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0)
42
43#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
44
45#define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
46#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
47#define roundup(x, y) ((((x) + ((y) - 1)) / (y)) * (y))
48
49#ifdef CONFIG_LBD
50# include <asm/div64.h>
51# define sector_div(a, b) do_div(a, b)
52#else
53# define sector_div(n, b)( \
54{ \
55 int _res; \
56 _res = (n) % (b); \
57 (n) /= (b); \
58 _res; \
59} \
60)
61#endif
62
63/**
64 * upper_32_bits - return bits 32-63 of a number
65 * @n: the number we're accessing
66 *
67 * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress
68 * the "right shift count >= width of type" warning when that quantity is
69 * 32-bits.
70 */
71#define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
72
73#define KERN_EMERG "<0>" /* system is unusable */
74#define KERN_ALERT "<1>" /* action must be taken immediately */
75#define KERN_CRIT "<2>" /* critical conditions */
76#define KERN_ERR "<3>" /* error conditions */
77#define KERN_WARNING "<4>" /* warning conditions */
78#define KERN_NOTICE "<5>" /* normal but significant condition */
79#define KERN_INFO "<6>" /* informational */
80#define KERN_DEBUG "<7>" /* debug-level messages */
81
82/*
83 * Annotation for a "continued" line of log printout (only done after a
84 * line that had no enclosing \n). Only to be used by core/arch code
85 * during early bootup (a continued line is not SMP-safe otherwise).
86 */
87#define KERN_CONT ""
88
89extern int console_printk[];
90
91#define console_loglevel (console_printk[0])
92#define default_message_loglevel (console_printk[1])
93#define minimum_console_loglevel (console_printk[2])
94#define default_console_loglevel (console_printk[3])
95
96struct completion;
97struct pt_regs;
98struct user;
99
100/**
101 * might_sleep - annotation for functions that can sleep
102 *
103 * this macro will print a stack trace if it is executed in an atomic
104 * context (spinlock, irq-handler, ...).
105 *
106 * This is a useful debugging help to be able to catch problems early and not
107 * be bitten later when the calling function happens to sleep when it is not
108 * supposed to.
109 */
110#ifdef CONFIG_PREEMPT_VOLUNTARY
111extern int _cond_resched(void);
112# define might_resched() _cond_resched()
113#else
114# define might_resched() do { } while (0)
115#endif
116
117#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
118 void __might_sleep(char *file, int line);
119# define might_sleep() \
120 do { __might_sleep(__FILE__, __LINE__); might_resched(); } while (0)
121#else
122# define might_sleep() do { might_resched(); } while (0)
123#endif
124
125#define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
126
127#define abs(x) ({ \
128 int __x = (x); \
129 (__x < 0) ? -__x : __x; \
130 })
131
132extern struct atomic_notifier_head panic_notifier_list;
133extern long (*panic_blink)(long time);
134NORET_TYPE void panic(const char * fmt, ...)
135 __attribute__ ((NORET_AND format (printf, 1, 2))) __cold;
136extern void oops_enter(void);
137extern void oops_exit(void);
138extern int oops_may_print(void);
139NORET_TYPE void do_exit(long error_code)
140 ATTRIB_NORET;
141NORET_TYPE void complete_and_exit(struct completion *, long)
142 ATTRIB_NORET;
143extern unsigned long simple_strtoul(const char *,char **,unsigned int);
144extern long simple_strtol(const char *,char **,unsigned int);
145extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
146extern long long simple_strtoll(const char *,char **,unsigned int);
147extern int strict_strtoul(const char *, unsigned int, unsigned long *);
148extern int strict_strtol(const char *, unsigned int, long *);
149extern int strict_strtoull(const char *, unsigned int, unsigned long long *);
150extern int strict_strtoll(const char *, unsigned int, long long *);
151extern int sprintf(char * buf, const char * fmt, ...)
152 __attribute__ ((format (printf, 2, 3)));
153extern int vsprintf(char *buf, const char *, va_list)
154 __attribute__ ((format (printf, 2, 0)));
155extern int snprintf(char * buf, size_t size, const char * fmt, ...)
156 __attribute__ ((format (printf, 3, 4)));
157extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
158 __attribute__ ((format (printf, 3, 0)));
159extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
160 __attribute__ ((format (printf, 3, 4)));
161extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
162 __attribute__ ((format (printf, 3, 0)));
163extern char *kasprintf(gfp_t gfp, const char *fmt, ...)
164 __attribute__ ((format (printf, 2, 3)));
165extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args);
166
167extern int sscanf(const char *, const char *, ...)
168 __attribute__ ((format (scanf, 2, 3)));
169extern int vsscanf(const char *, const char *, va_list)
170 __attribute__ ((format (scanf, 2, 0)));
171
172extern int get_option(char **str, int *pint);
173extern char *get_options(const char *str, int nints, int *ints);
174extern unsigned long long memparse(char *ptr, char **retptr);
175
176extern int core_kernel_text(unsigned long addr);
177extern int __kernel_text_address(unsigned long addr);
178extern int kernel_text_address(unsigned long addr);
179struct pid;
180extern struct pid *session_of_pgrp(struct pid *pgrp);
181
182#ifdef CONFIG_PRINTK
183asmlinkage int vprintk(const char *fmt, va_list args)
184 __attribute__ ((format (printf, 1, 0)));
185asmlinkage int printk(const char * fmt, ...)
186 __attribute__ ((format (printf, 1, 2))) __cold;
187extern int log_buf_get_len(void);
188extern int log_buf_read(int idx);
189extern int log_buf_copy(char *dest, int idx, int len);
190
191extern int printk_ratelimit_jiffies;
192extern int printk_ratelimit_burst;
193extern int printk_ratelimit(void);
194extern int __ratelimit(int ratelimit_jiffies, int ratelimit_burst);
195extern int __printk_ratelimit(int ratelimit_jiffies, int ratelimit_burst);
196extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
197 unsigned int interval_msec);
198#else
199static inline int vprintk(const char *s, va_list args)
200 __attribute__ ((format (printf, 1, 0)));
201static inline int vprintk(const char *s, va_list args) { return 0; }
202static inline int printk(const char *s, ...)
203 __attribute__ ((format (printf, 1, 2)));
204static inline int __cold printk(const char *s, ...) { return 0; }
205static inline int log_buf_get_len(void) { return 0; }
206static inline int log_buf_read(int idx) { return 0; }
207static inline int log_buf_copy(char *dest, int idx, int len) { return 0; }
208static inline int printk_ratelimit(void) { return 0; }
209static inline int __printk_ratelimit(int ratelimit_jiffies, \
210 int ratelimit_burst) { return 0; }
211static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies, \
212 unsigned int interval_msec) \
213 { return false; }
214#endif
215
216extern void __attribute__((format(printf, 1, 2)))
217 early_printk(const char *fmt, ...);
218
219unsigned long int_sqrt(unsigned long);
220
221static inline void console_silent(void)
222{
223 console_loglevel = 0;
224}
225
226static inline void console_verbose(void)
227{
228 if (console_loglevel)
229 console_loglevel = 15;
230}
231
232extern void bust_spinlocks(int yes);
233extern void wake_up_klogd(void);
234extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */
235extern int panic_timeout;
236extern int panic_on_oops;
237extern int panic_on_unrecovered_nmi;
238extern int tainted;
239extern const char *print_tainted(void);
240extern void add_taint(unsigned);
241extern int root_mountflags;
242
243/* Values used for system_state */
244extern enum system_states {
245 SYSTEM_BOOTING,
246 SYSTEM_RUNNING,
247 SYSTEM_HALT,
248 SYSTEM_POWER_OFF,
249 SYSTEM_RESTART,
250 SYSTEM_SUSPEND_DISK,
251} system_state;
252
253#define TAINT_PROPRIETARY_MODULE (1<<0)
254#define TAINT_FORCED_MODULE (1<<1)
255#define TAINT_UNSAFE_SMP (1<<2)
256#define TAINT_FORCED_RMMOD (1<<3)
257#define TAINT_MACHINE_CHECK (1<<4)
258#define TAINT_BAD_PAGE (1<<5)
259#define TAINT_USER (1<<6)
260#define TAINT_DIE (1<<7)
261#define TAINT_OVERRIDDEN_ACPI_TABLE (1<<8)
262#define TAINT_WARN (1<<9)
263
264extern void dump_stack(void) __cold;
265
266enum {
267 DUMP_PREFIX_NONE,
268 DUMP_PREFIX_ADDRESS,
269 DUMP_PREFIX_OFFSET
270};
271extern void hex_dump_to_buffer(const void *buf, size_t len,
272 int rowsize, int groupsize,
273 char *linebuf, size_t linebuflen, bool ascii);
274extern void print_hex_dump(const char *level, const char *prefix_str,
275 int prefix_type, int rowsize, int groupsize,
276 const void *buf, size_t len, bool ascii);
277extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
278 const void *buf, size_t len);
279
280extern const char hex_asc[];
281#define hex_asc_lo(x) hex_asc[((x) & 0x0f)]
282#define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4]
283
284static inline char *pack_hex_byte(char *buf, u8 byte)
285{
286 *buf++ = hex_asc_hi(byte);
287 *buf++ = hex_asc_lo(byte);
288 return buf;
289}
290
291#define pr_emerg(fmt, arg...) \
292 printk(KERN_EMERG fmt, ##arg)
293#define pr_alert(fmt, arg...) \
294 printk(KERN_ALERT fmt, ##arg)
295#define pr_crit(fmt, arg...) \
296 printk(KERN_CRIT fmt, ##arg)
297#define pr_err(fmt, arg...) \
298 printk(KERN_ERR fmt, ##arg)
299#define pr_warning(fmt, arg...) \
300 printk(KERN_WARNING fmt, ##arg)
301#define pr_notice(fmt, arg...) \
302 printk(KERN_NOTICE fmt, ##arg)
303#define pr_info(fmt, arg...) \
304 printk(KERN_INFO fmt, ##arg)
305
306#ifdef DEBUG
307/* If you are writing a driver, please use dev_dbg instead */
308#define pr_debug(fmt, arg...) \
309 printk(KERN_DEBUG fmt, ##arg)
310#else
311#define pr_debug(fmt, arg...) \
312 ({ if (0) printk(KERN_DEBUG fmt, ##arg); 0; })
313#endif
314
315/*
316 * Display an IP address in readable format.
317 */
318
319#define NIPQUAD(addr) \
320 ((unsigned char *)&addr)[0], \
321 ((unsigned char *)&addr)[1], \
322 ((unsigned char *)&addr)[2], \
323 ((unsigned char *)&addr)[3]
324#define NIPQUAD_FMT "%u.%u.%u.%u"
325
326#define NIP6(addr) \
327 ntohs((addr).s6_addr16[0]), \
328 ntohs((addr).s6_addr16[1]), \
329 ntohs((addr).s6_addr16[2]), \
330 ntohs((addr).s6_addr16[3]), \
331 ntohs((addr).s6_addr16[4]), \
332 ntohs((addr).s6_addr16[5]), \
333 ntohs((addr).s6_addr16[6]), \
334 ntohs((addr).s6_addr16[7])
335#define NIP6_FMT "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x"
336#define NIP6_SEQFMT "%04x%04x%04x%04x%04x%04x%04x%04x"
337
338#if defined(__LITTLE_ENDIAN)
339#define HIPQUAD(addr) \
340 ((unsigned char *)&addr)[3], \
341 ((unsigned char *)&addr)[2], \
342 ((unsigned char *)&addr)[1], \
343 ((unsigned char *)&addr)[0]
344#elif defined(__BIG_ENDIAN)
345#define HIPQUAD NIPQUAD
346#else
347#error "Please fix asm/byteorder.h"
348#endif /* __LITTLE_ENDIAN */
349
350/*
351 * min()/max()/clamp() macros that also do
352 * strict type-checking.. See the
353 * "unnecessary" pointer comparison.
354 */
355#define min(x, y) ({ \
356 typeof(x) _min1 = (x); \
357 typeof(y) _min2 = (y); \
358 (void) (&_min1 == &_min2); \
359 _min1 < _min2 ? _min1 : _min2; })
360
361#define max(x, y) ({ \
362 typeof(x) _max1 = (x); \
363 typeof(y) _max2 = (y); \
364 (void) (&_max1 == &_max2); \
365 _max1 > _max2 ? _max1 : _max2; })
366
367/**
368 * clamp - return a value clamped to a given range with strict typechecking
369 * @val: current value
370 * @min: minimum allowable value
371 * @max: maximum allowable value
372 *
373 * This macro does strict typechecking of min/max to make sure they are of the
374 * same type as val. See the unnecessary pointer comparisons.
375 */
376#define clamp(val, min, max) ({ \
377 typeof(val) __val = (val); \
378 typeof(min) __min = (min); \
379 typeof(max) __max = (max); \
380 (void) (&__val == &__min); \
381 (void) (&__val == &__max); \
382 __val = __val < __min ? __min: __val; \
383 __val > __max ? __max: __val; })
384
385/*
386 * ..and if you can't take the strict
387 * types, you can specify one yourself.
388 *
389 * Or not use min/max/clamp at all, of course.
390 */
391#define min_t(type, x, y) ({ \
392 type __min1 = (x); \
393 type __min2 = (y); \
394 __min1 < __min2 ? __min1: __min2; })
395
396#define max_t(type, x, y) ({ \
397 type __max1 = (x); \
398 type __max2 = (y); \
399 __max1 > __max2 ? __max1: __max2; })
400
401/**
402 * clamp_t - return a value clamped to a given range using a given type
403 * @type: the type of variable to use
404 * @val: current value
405 * @min: minimum allowable value
406 * @max: maximum allowable value
407 *
408 * This macro does no typechecking and uses temporary variables of type
409 * 'type' to make all the comparisons.
410 */
411#define clamp_t(type, val, min, max) ({ \
412 type __val = (val); \
413 type __min = (min); \
414 type __max = (max); \
415 __val = __val < __min ? __min: __val; \
416 __val > __max ? __max: __val; })
417
418/**
419 * clamp_val - return a value clamped to a given range using val's type
420 * @val: current value
421 * @min: minimum allowable value
422 * @max: maximum allowable value
423 *
424 * This macro does no typechecking and uses temporary variables of whatever
425 * type the input argument 'val' is. This is useful when val is an unsigned
426 * type and min and max are literals that will otherwise be assigned a signed
427 * integer type.
428 */
429#define clamp_val(val, min, max) ({ \
430 typeof(val) __val = (val); \
431 typeof(val) __min = (min); \
432 typeof(val) __max = (max); \
433 __val = __val < __min ? __min: __val; \
434 __val > __max ? __max: __val; })
435
436/**
437 * container_of - cast a member of a structure out to the containing structure
438 * @ptr: the pointer to the member.
439 * @type: the type of the container struct this is embedded in.
440 * @member: the name of the member within the struct.
441 *
442 */
443#define container_of(ptr, type, member) ({ \
444 const typeof( ((type *)0)->member ) *__mptr = (ptr); \
445 (type *)( (char *)__mptr - offsetof(type,member) );})
446
447/*
448 * Check at compile time that something is of a particular type.
449 * Always evaluates to 1 so you may use it easily in comparisons.
450 */
451#define typecheck(type,x) \
452({ type __dummy; \
453 typeof(x) __dummy2; \
454 (void)(&__dummy == &__dummy2); \
455 1; \
456})
457
458/*
459 * Check at compile time that 'function' is a certain type, or is a pointer
460 * to that type (needs to use typedef for the function type.)
461 */
462#define typecheck_fn(type,function) \
463({ typeof(type) __tmp = function; \
464 (void)__tmp; \
465})
466
467struct sysinfo;
468extern int do_sysinfo(struct sysinfo *info);
469
470#endif /* __KERNEL__ */
471
472#define SI_LOAD_SHIFT 16
473struct sysinfo {
474 long uptime; /* Seconds since boot */
475 unsigned long loads[3]; /* 1, 5, and 15 minute load averages */
476 unsigned long totalram; /* Total usable main memory size */
477 unsigned long freeram; /* Available memory size */
478 unsigned long sharedram; /* Amount of shared memory */
479 unsigned long bufferram; /* Memory used by buffers */
480 unsigned long totalswap; /* Total swap space size */
481 unsigned long freeswap; /* swap space still available */
482 unsigned short procs; /* Number of current processes */
483 unsigned short pad; /* explicit padding for m68k */
484 unsigned long totalhigh; /* Total high memory size */
485 unsigned long freehigh; /* Available high memory size */
486 unsigned int mem_unit; /* Memory unit size in bytes */
487 char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */
488};
489
490/* Force a compilation error if condition is true */
491#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
492
493/* Force a compilation error if condition is true, but also produce a
494 result (of value 0 and type size_t), so the expression can be used
495 e.g. in a structure initializer (or where-ever else comma expressions
496 aren't permitted). */
497#define BUILD_BUG_ON_ZERO(e) (sizeof(char[1 - 2 * !!(e)]) - 1)
498
499/* Trap pasters of __FUNCTION__ at compile-time */
500#define __FUNCTION__ (__func__)
501
502/* This helps us to avoid #ifdef CONFIG_NUMA */
503#ifdef CONFIG_NUMA
504#define NUMA_BUILD 1
505#else
506#define NUMA_BUILD 0
507#endif
508
509#endif