Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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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#define _RET_IP_ (unsigned long)__builtin_return_address(0)
50#define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; })
51
52#ifdef CONFIG_LBD
53# include <asm/div64.h>
54# define sector_div(a, b) do_div(a, b)
55#else
56# define sector_div(n, b)( \
57{ \
58 int _res; \
59 _res = (n) % (b); \
60 (n) /= (b); \
61 _res; \
62} \
63)
64#endif
65
66/**
67 * upper_32_bits - return bits 32-63 of a number
68 * @n: the number we're accessing
69 *
70 * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress
71 * the "right shift count >= width of type" warning when that quantity is
72 * 32-bits.
73 */
74#define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
75
76#define KERN_EMERG "<0>" /* system is unusable */
77#define KERN_ALERT "<1>" /* action must be taken immediately */
78#define KERN_CRIT "<2>" /* critical conditions */
79#define KERN_ERR "<3>" /* error conditions */
80#define KERN_WARNING "<4>" /* warning conditions */
81#define KERN_NOTICE "<5>" /* normal but significant condition */
82#define KERN_INFO "<6>" /* informational */
83#define KERN_DEBUG "<7>" /* debug-level messages */
84
85/*
86 * Annotation for a "continued" line of log printout (only done after a
87 * line that had no enclosing \n). Only to be used by core/arch code
88 * during early bootup (a continued line is not SMP-safe otherwise).
89 */
90#define KERN_CONT ""
91
92extern int console_printk[];
93
94#define console_loglevel (console_printk[0])
95#define default_message_loglevel (console_printk[1])
96#define minimum_console_loglevel (console_printk[2])
97#define default_console_loglevel (console_printk[3])
98
99struct completion;
100struct pt_regs;
101struct user;
102
103/**
104 * might_sleep - annotation for functions that can sleep
105 *
106 * this macro will print a stack trace if it is executed in an atomic
107 * context (spinlock, irq-handler, ...).
108 *
109 * This is a useful debugging help to be able to catch problems early and not
110 * be bitten later when the calling function happens to sleep when it is not
111 * supposed to.
112 */
113#ifdef CONFIG_PREEMPT_VOLUNTARY
114extern int _cond_resched(void);
115# define might_resched() _cond_resched()
116#else
117# define might_resched() do { } while (0)
118#endif
119
120#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
121 void __might_sleep(char *file, int line);
122# define might_sleep() \
123 do { __might_sleep(__FILE__, __LINE__); might_resched(); } while (0)
124#else
125# define might_sleep() do { might_resched(); } while (0)
126#endif
127
128#define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
129
130#define abs(x) ({ \
131 int __x = (x); \
132 (__x < 0) ? -__x : __x; \
133 })
134
135extern struct atomic_notifier_head panic_notifier_list;
136extern long (*panic_blink)(long time);
137NORET_TYPE void panic(const char * fmt, ...)
138 __attribute__ ((NORET_AND format (printf, 1, 2))) __cold;
139extern void oops_enter(void);
140extern void oops_exit(void);
141extern int oops_may_print(void);
142NORET_TYPE void do_exit(long error_code)
143 ATTRIB_NORET;
144NORET_TYPE void complete_and_exit(struct completion *, long)
145 ATTRIB_NORET;
146extern unsigned long simple_strtoul(const char *,char **,unsigned int);
147extern long simple_strtol(const char *,char **,unsigned int);
148extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
149extern long long simple_strtoll(const char *,char **,unsigned int);
150extern int strict_strtoul(const char *, unsigned int, unsigned long *);
151extern int strict_strtol(const char *, unsigned int, long *);
152extern int strict_strtoull(const char *, unsigned int, unsigned long long *);
153extern int strict_strtoll(const char *, unsigned int, long long *);
154extern int sprintf(char * buf, const char * fmt, ...)
155 __attribute__ ((format (printf, 2, 3)));
156extern int vsprintf(char *buf, const char *, va_list)
157 __attribute__ ((format (printf, 2, 0)));
158extern int snprintf(char * buf, size_t size, const char * fmt, ...)
159 __attribute__ ((format (printf, 3, 4)));
160extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
161 __attribute__ ((format (printf, 3, 0)));
162extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
163 __attribute__ ((format (printf, 3, 4)));
164extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
165 __attribute__ ((format (printf, 3, 0)));
166extern char *kasprintf(gfp_t gfp, const char *fmt, ...)
167 __attribute__ ((format (printf, 2, 3)));
168extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args);
169
170extern int sscanf(const char *, const char *, ...)
171 __attribute__ ((format (scanf, 2, 3)));
172extern int vsscanf(const char *, const char *, va_list)
173 __attribute__ ((format (scanf, 2, 0)));
174
175extern int get_option(char **str, int *pint);
176extern char *get_options(const char *str, int nints, int *ints);
177extern unsigned long long memparse(char *ptr, char **retptr);
178
179extern int core_kernel_text(unsigned long addr);
180extern int __kernel_text_address(unsigned long addr);
181extern int kernel_text_address(unsigned long addr);
182struct pid;
183extern struct pid *session_of_pgrp(struct pid *pgrp);
184
185#ifdef CONFIG_PRINTK
186asmlinkage int vprintk(const char *fmt, va_list args)
187 __attribute__ ((format (printf, 1, 0)));
188asmlinkage int printk(const char * fmt, ...)
189 __attribute__ ((format (printf, 1, 2))) __cold;
190extern int log_buf_get_len(void);
191extern int log_buf_read(int idx);
192extern int log_buf_copy(char *dest, int idx, int len);
193
194extern int printk_ratelimit_jiffies;
195extern int printk_ratelimit_burst;
196extern int printk_ratelimit(void);
197extern int __ratelimit(int ratelimit_jiffies, int ratelimit_burst);
198extern int __printk_ratelimit(int ratelimit_jiffies, int ratelimit_burst);
199extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
200 unsigned int interval_msec);
201#else
202static inline int vprintk(const char *s, va_list args)
203 __attribute__ ((format (printf, 1, 0)));
204static inline int vprintk(const char *s, va_list args) { return 0; }
205static inline int printk(const char *s, ...)
206 __attribute__ ((format (printf, 1, 2)));
207static inline int __cold printk(const char *s, ...) { return 0; }
208static inline int log_buf_get_len(void) { return 0; }
209static inline int log_buf_read(int idx) { return 0; }
210static inline int log_buf_copy(char *dest, int idx, int len) { return 0; }
211static inline int printk_ratelimit(void) { return 0; }
212static inline int __printk_ratelimit(int ratelimit_jiffies, \
213 int ratelimit_burst) { return 0; }
214static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies, \
215 unsigned int interval_msec) \
216 { return false; }
217#endif
218
219extern void __attribute__((format(printf, 1, 2)))
220 early_printk(const char *fmt, ...);
221
222unsigned long int_sqrt(unsigned long);
223
224static inline void console_silent(void)
225{
226 console_loglevel = 0;
227}
228
229static inline void console_verbose(void)
230{
231 if (console_loglevel)
232 console_loglevel = 15;
233}
234
235extern void bust_spinlocks(int yes);
236extern void wake_up_klogd(void);
237extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */
238extern int panic_timeout;
239extern int panic_on_oops;
240extern int panic_on_unrecovered_nmi;
241extern int tainted;
242extern const char *print_tainted(void);
243extern void add_taint(unsigned);
244extern int root_mountflags;
245
246/* Values used for system_state */
247extern enum system_states {
248 SYSTEM_BOOTING,
249 SYSTEM_RUNNING,
250 SYSTEM_HALT,
251 SYSTEM_POWER_OFF,
252 SYSTEM_RESTART,
253 SYSTEM_SUSPEND_DISK,
254} system_state;
255
256#define TAINT_PROPRIETARY_MODULE (1<<0)
257#define TAINT_FORCED_MODULE (1<<1)
258#define TAINT_UNSAFE_SMP (1<<2)
259#define TAINT_FORCED_RMMOD (1<<3)
260#define TAINT_MACHINE_CHECK (1<<4)
261#define TAINT_BAD_PAGE (1<<5)
262#define TAINT_USER (1<<6)
263#define TAINT_DIE (1<<7)
264#define TAINT_OVERRIDDEN_ACPI_TABLE (1<<8)
265#define TAINT_WARN (1<<9)
266
267extern void dump_stack(void) __cold;
268
269enum {
270 DUMP_PREFIX_NONE,
271 DUMP_PREFIX_ADDRESS,
272 DUMP_PREFIX_OFFSET
273};
274extern void hex_dump_to_buffer(const void *buf, size_t len,
275 int rowsize, int groupsize,
276 char *linebuf, size_t linebuflen, bool ascii);
277extern void print_hex_dump(const char *level, const char *prefix_str,
278 int prefix_type, int rowsize, int groupsize,
279 const void *buf, size_t len, bool ascii);
280extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
281 const void *buf, size_t len);
282
283extern const char hex_asc[];
284#define hex_asc_lo(x) hex_asc[((x) & 0x0f)]
285#define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4]
286
287static inline char *pack_hex_byte(char *buf, u8 byte)
288{
289 *buf++ = hex_asc_hi(byte);
290 *buf++ = hex_asc_lo(byte);
291 return buf;
292}
293
294#define pr_emerg(fmt, arg...) \
295 printk(KERN_EMERG fmt, ##arg)
296#define pr_alert(fmt, arg...) \
297 printk(KERN_ALERT fmt, ##arg)
298#define pr_crit(fmt, arg...) \
299 printk(KERN_CRIT fmt, ##arg)
300#define pr_err(fmt, arg...) \
301 printk(KERN_ERR fmt, ##arg)
302#define pr_warning(fmt, arg...) \
303 printk(KERN_WARNING fmt, ##arg)
304#define pr_notice(fmt, arg...) \
305 printk(KERN_NOTICE fmt, ##arg)
306#define pr_info(fmt, arg...) \
307 printk(KERN_INFO fmt, ##arg)
308
309#ifdef DEBUG
310/* If you are writing a driver, please use dev_dbg instead */
311#define pr_debug(fmt, arg...) \
312 printk(KERN_DEBUG fmt, ##arg)
313#else
314#define pr_debug(fmt, arg...) \
315 ({ if (0) printk(KERN_DEBUG fmt, ##arg); 0; })
316#endif
317
318/*
319 * Display an IP address in readable format.
320 */
321
322#define NIPQUAD(addr) \
323 ((unsigned char *)&addr)[0], \
324 ((unsigned char *)&addr)[1], \
325 ((unsigned char *)&addr)[2], \
326 ((unsigned char *)&addr)[3]
327#define NIPQUAD_FMT "%u.%u.%u.%u"
328
329#define NIP6(addr) \
330 ntohs((addr).s6_addr16[0]), \
331 ntohs((addr).s6_addr16[1]), \
332 ntohs((addr).s6_addr16[2]), \
333 ntohs((addr).s6_addr16[3]), \
334 ntohs((addr).s6_addr16[4]), \
335 ntohs((addr).s6_addr16[5]), \
336 ntohs((addr).s6_addr16[6]), \
337 ntohs((addr).s6_addr16[7])
338#define NIP6_FMT "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x"
339#define NIP6_SEQFMT "%04x%04x%04x%04x%04x%04x%04x%04x"
340
341#if defined(__LITTLE_ENDIAN)
342#define HIPQUAD(addr) \
343 ((unsigned char *)&addr)[3], \
344 ((unsigned char *)&addr)[2], \
345 ((unsigned char *)&addr)[1], \
346 ((unsigned char *)&addr)[0]
347#elif defined(__BIG_ENDIAN)
348#define HIPQUAD NIPQUAD
349#else
350#error "Please fix asm/byteorder.h"
351#endif /* __LITTLE_ENDIAN */
352
353/*
354 * min()/max()/clamp() macros that also do
355 * strict type-checking.. See the
356 * "unnecessary" pointer comparison.
357 */
358#define min(x, y) ({ \
359 typeof(x) _min1 = (x); \
360 typeof(y) _min2 = (y); \
361 (void) (&_min1 == &_min2); \
362 _min1 < _min2 ? _min1 : _min2; })
363
364#define max(x, y) ({ \
365 typeof(x) _max1 = (x); \
366 typeof(y) _max2 = (y); \
367 (void) (&_max1 == &_max2); \
368 _max1 > _max2 ? _max1 : _max2; })
369
370/**
371 * clamp - return a value clamped to a given range with strict typechecking
372 * @val: current value
373 * @min: minimum allowable value
374 * @max: maximum allowable value
375 *
376 * This macro does strict typechecking of min/max to make sure they are of the
377 * same type as val. See the unnecessary pointer comparisons.
378 */
379#define clamp(val, min, max) ({ \
380 typeof(val) __val = (val); \
381 typeof(min) __min = (min); \
382 typeof(max) __max = (max); \
383 (void) (&__val == &__min); \
384 (void) (&__val == &__max); \
385 __val = __val < __min ? __min: __val; \
386 __val > __max ? __max: __val; })
387
388/*
389 * ..and if you can't take the strict
390 * types, you can specify one yourself.
391 *
392 * Or not use min/max/clamp at all, of course.
393 */
394#define min_t(type, x, y) ({ \
395 type __min1 = (x); \
396 type __min2 = (y); \
397 __min1 < __min2 ? __min1: __min2; })
398
399#define max_t(type, x, y) ({ \
400 type __max1 = (x); \
401 type __max2 = (y); \
402 __max1 > __max2 ? __max1: __max2; })
403
404/**
405 * clamp_t - return a value clamped to a given range using a given type
406 * @type: the type of variable to use
407 * @val: current value
408 * @min: minimum allowable value
409 * @max: maximum allowable value
410 *
411 * This macro does no typechecking and uses temporary variables of type
412 * 'type' to make all the comparisons.
413 */
414#define clamp_t(type, val, min, max) ({ \
415 type __val = (val); \
416 type __min = (min); \
417 type __max = (max); \
418 __val = __val < __min ? __min: __val; \
419 __val > __max ? __max: __val; })
420
421/**
422 * clamp_val - return a value clamped to a given range using val's type
423 * @val: current value
424 * @min: minimum allowable value
425 * @max: maximum allowable value
426 *
427 * This macro does no typechecking and uses temporary variables of whatever
428 * type the input argument 'val' is. This is useful when val is an unsigned
429 * type and min and max are literals that will otherwise be assigned a signed
430 * integer type.
431 */
432#define clamp_val(val, min, max) ({ \
433 typeof(val) __val = (val); \
434 typeof(val) __min = (min); \
435 typeof(val) __max = (max); \
436 __val = __val < __min ? __min: __val; \
437 __val > __max ? __max: __val; })
438
439/**
440 * container_of - cast a member of a structure out to the containing structure
441 * @ptr: the pointer to the member.
442 * @type: the type of the container struct this is embedded in.
443 * @member: the name of the member within the struct.
444 *
445 */
446#define container_of(ptr, type, member) ({ \
447 const typeof( ((type *)0)->member ) *__mptr = (ptr); \
448 (type *)( (char *)__mptr - offsetof(type,member) );})
449
450/*
451 * Check at compile time that something is of a particular type.
452 * Always evaluates to 1 so you may use it easily in comparisons.
453 */
454#define typecheck(type,x) \
455({ type __dummy; \
456 typeof(x) __dummy2; \
457 (void)(&__dummy == &__dummy2); \
458 1; \
459})
460
461/*
462 * Check at compile time that 'function' is a certain type, or is a pointer
463 * to that type (needs to use typedef for the function type.)
464 */
465#define typecheck_fn(type,function) \
466({ typeof(type) __tmp = function; \
467 (void)__tmp; \
468})
469
470struct sysinfo;
471extern int do_sysinfo(struct sysinfo *info);
472
473#endif /* __KERNEL__ */
474
475#define SI_LOAD_SHIFT 16
476struct sysinfo {
477 long uptime; /* Seconds since boot */
478 unsigned long loads[3]; /* 1, 5, and 15 minute load averages */
479 unsigned long totalram; /* Total usable main memory size */
480 unsigned long freeram; /* Available memory size */
481 unsigned long sharedram; /* Amount of shared memory */
482 unsigned long bufferram; /* Memory used by buffers */
483 unsigned long totalswap; /* Total swap space size */
484 unsigned long freeswap; /* swap space still available */
485 unsigned short procs; /* Number of current processes */
486 unsigned short pad; /* explicit padding for m68k */
487 unsigned long totalhigh; /* Total high memory size */
488 unsigned long freehigh; /* Available high memory size */
489 unsigned int mem_unit; /* Memory unit size in bytes */
490 char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */
491};
492
493/* Force a compilation error if condition is true */
494#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
495
496/* Force a compilation error if condition is true, but also produce a
497 result (of value 0 and type size_t), so the expression can be used
498 e.g. in a structure initializer (or where-ever else comma expressions
499 aren't permitted). */
500#define BUILD_BUG_ON_ZERO(e) (sizeof(char[1 - 2 * !!(e)]) - 1)
501
502/* Trap pasters of __FUNCTION__ at compile-time */
503#define __FUNCTION__ (__func__)
504
505/* This helps us to avoid #ifdef CONFIG_NUMA */
506#ifdef CONFIG_NUMA
507#define NUMA_BUILD 1
508#else
509#define NUMA_BUILD 0
510#endif
511
512#endif