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 <linux/typecheck.h>
18#include <linux/ratelimit.h>
19#include <linux/dynamic_printk.h>
20#include <asm/byteorder.h>
21#include <asm/bug.h>
22
23extern const char linux_banner[];
24extern const char linux_proc_banner[];
25
26#define USHORT_MAX ((u16)(~0U))
27#define SHORT_MAX ((s16)(USHORT_MAX>>1))
28#define SHORT_MIN (-SHORT_MAX - 1)
29#define INT_MAX ((int)(~0U>>1))
30#define INT_MIN (-INT_MAX - 1)
31#define UINT_MAX (~0U)
32#define LONG_MAX ((long)(~0UL>>1))
33#define LONG_MIN (-LONG_MAX - 1)
34#define ULONG_MAX (~0UL)
35#define LLONG_MAX ((long long)(~0ULL>>1))
36#define LLONG_MIN (-LLONG_MAX - 1)
37#define ULLONG_MAX (~0ULL)
38
39#define STACK_MAGIC 0xdeadbeef
40
41#define ALIGN(x,a) __ALIGN_MASK(x,(typeof(x))(a)-1)
42#define __ALIGN_MASK(x,mask) (((x)+(mask))&~(mask))
43#define PTR_ALIGN(p, a) ((typeof(p))ALIGN((unsigned long)(p), (a)))
44#define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0)
45
46#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
47
48#define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
49#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
50#define roundup(x, y) ((((x) + ((y) - 1)) / (y)) * (y))
51
52#define _RET_IP_ (unsigned long)__builtin_return_address(0)
53#define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; })
54
55#ifdef CONFIG_LBD
56# include <asm/div64.h>
57# define sector_div(a, b) do_div(a, b)
58#else
59# define sector_div(n, b)( \
60{ \
61 int _res; \
62 _res = (n) % (b); \
63 (n) /= (b); \
64 _res; \
65} \
66)
67#endif
68
69/**
70 * upper_32_bits - return bits 32-63 of a number
71 * @n: the number we're accessing
72 *
73 * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress
74 * the "right shift count >= width of type" warning when that quantity is
75 * 32-bits.
76 */
77#define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
78
79/**
80 * lower_32_bits - return bits 0-31 of a number
81 * @n: the number we're accessing
82 */
83#define lower_32_bits(n) ((u32)(n))
84
85#define KERN_EMERG "<0>" /* system is unusable */
86#define KERN_ALERT "<1>" /* action must be taken immediately */
87#define KERN_CRIT "<2>" /* critical conditions */
88#define KERN_ERR "<3>" /* error conditions */
89#define KERN_WARNING "<4>" /* warning conditions */
90#define KERN_NOTICE "<5>" /* normal but significant condition */
91#define KERN_INFO "<6>" /* informational */
92#define KERN_DEBUG "<7>" /* debug-level messages */
93
94/*
95 * Annotation for a "continued" line of log printout (only done after a
96 * line that had no enclosing \n). Only to be used by core/arch code
97 * during early bootup (a continued line is not SMP-safe otherwise).
98 */
99#define KERN_CONT ""
100
101extern int console_printk[];
102
103#define console_loglevel (console_printk[0])
104#define default_message_loglevel (console_printk[1])
105#define minimum_console_loglevel (console_printk[2])
106#define default_console_loglevel (console_printk[3])
107
108struct completion;
109struct pt_regs;
110struct user;
111
112#ifdef CONFIG_PREEMPT_VOLUNTARY
113extern int _cond_resched(void);
114# define might_resched() _cond_resched()
115#else
116# define might_resched() do { } while (0)
117#endif
118
119/**
120 * might_sleep - annotation for functions that can sleep
121 *
122 * this macro will print a stack trace if it is executed in an atomic
123 * context (spinlock, irq-handler, ...).
124 *
125 * This is a useful debugging help to be able to catch problems early and not
126 * be bitten later when the calling function happens to sleep when it is not
127 * supposed to.
128 */
129#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
130 void __might_sleep(char *file, int line);
131# define might_sleep() \
132 do { __might_sleep(__FILE__, __LINE__); might_resched(); } while (0)
133#else
134# define might_sleep() do { might_resched(); } while (0)
135#endif
136
137#define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
138
139#define abs(x) ({ \
140 int __x = (x); \
141 (__x < 0) ? -__x : __x; \
142 })
143
144extern struct atomic_notifier_head panic_notifier_list;
145extern long (*panic_blink)(long time);
146NORET_TYPE void panic(const char * fmt, ...)
147 __attribute__ ((NORET_AND format (printf, 1, 2))) __cold;
148extern void oops_enter(void);
149extern void oops_exit(void);
150extern int oops_may_print(void);
151NORET_TYPE void do_exit(long error_code)
152 ATTRIB_NORET;
153NORET_TYPE void complete_and_exit(struct completion *, long)
154 ATTRIB_NORET;
155extern unsigned long simple_strtoul(const char *,char **,unsigned int);
156extern long simple_strtol(const char *,char **,unsigned int);
157extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
158extern long long simple_strtoll(const char *,char **,unsigned int);
159extern int strict_strtoul(const char *, unsigned int, unsigned long *);
160extern int strict_strtol(const char *, unsigned int, long *);
161extern int strict_strtoull(const char *, unsigned int, unsigned long long *);
162extern int strict_strtoll(const char *, unsigned int, long long *);
163extern int sprintf(char * buf, const char * fmt, ...)
164 __attribute__ ((format (printf, 2, 3)));
165extern int vsprintf(char *buf, const char *, va_list)
166 __attribute__ ((format (printf, 2, 0)));
167extern int snprintf(char * buf, size_t size, const char * fmt, ...)
168 __attribute__ ((format (printf, 3, 4)));
169extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
170 __attribute__ ((format (printf, 3, 0)));
171extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
172 __attribute__ ((format (printf, 3, 4)));
173extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
174 __attribute__ ((format (printf, 3, 0)));
175extern char *kasprintf(gfp_t gfp, const char *fmt, ...)
176 __attribute__ ((format (printf, 2, 3)));
177extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args);
178
179extern int sscanf(const char *, const char *, ...)
180 __attribute__ ((format (scanf, 2, 3)));
181extern int vsscanf(const char *, const char *, va_list)
182 __attribute__ ((format (scanf, 2, 0)));
183
184extern int get_option(char **str, int *pint);
185extern char *get_options(const char *str, int nints, int *ints);
186extern unsigned long long memparse(const char *ptr, char **retptr);
187
188extern int core_kernel_text(unsigned long addr);
189extern int __kernel_text_address(unsigned long addr);
190extern int kernel_text_address(unsigned long addr);
191struct pid;
192extern struct pid *session_of_pgrp(struct pid *pgrp);
193
194#ifdef CONFIG_PRINTK
195asmlinkage int vprintk(const char *fmt, va_list args)
196 __attribute__ ((format (printf, 1, 0)));
197asmlinkage int printk(const char * fmt, ...)
198 __attribute__ ((format (printf, 1, 2))) __cold;
199
200extern struct ratelimit_state printk_ratelimit_state;
201extern int printk_ratelimit(void);
202extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
203 unsigned int interval_msec);
204#else
205static inline int vprintk(const char *s, va_list args)
206 __attribute__ ((format (printf, 1, 0)));
207static inline int vprintk(const char *s, va_list args) { return 0; }
208static inline int printk(const char *s, ...)
209 __attribute__ ((format (printf, 1, 2)));
210static inline int __cold printk(const char *s, ...) { return 0; }
211static inline int printk_ratelimit(void) { return 0; }
212static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies, \
213 unsigned int interval_msec) \
214 { return false; }
215#endif
216
217extern int printk_needs_cpu(int cpu);
218extern void printk_tick(void);
219
220extern void asmlinkage __attribute__((format(printf, 1, 2)))
221 early_printk(const char *fmt, ...);
222
223unsigned long int_sqrt(unsigned long);
224
225static inline void console_silent(void)
226{
227 console_loglevel = 0;
228}
229
230static inline void console_verbose(void)
231{
232 if (console_loglevel)
233 console_loglevel = 15;
234}
235
236extern void bust_spinlocks(int yes);
237extern void wake_up_klogd(void);
238extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */
239extern int panic_timeout;
240extern int panic_on_oops;
241extern int panic_on_unrecovered_nmi;
242extern const char *print_tainted(void);
243extern void add_taint(unsigned flag);
244extern int test_taint(unsigned flag);
245extern unsigned long get_taint(void);
246extern int root_mountflags;
247
248/* Values used for system_state */
249extern enum system_states {
250 SYSTEM_BOOTING,
251 SYSTEM_RUNNING,
252 SYSTEM_HALT,
253 SYSTEM_POWER_OFF,
254 SYSTEM_RESTART,
255 SYSTEM_SUSPEND_DISK,
256} system_state;
257
258#define TAINT_PROPRIETARY_MODULE 0
259#define TAINT_FORCED_MODULE 1
260#define TAINT_UNSAFE_SMP 2
261#define TAINT_FORCED_RMMOD 3
262#define TAINT_MACHINE_CHECK 4
263#define TAINT_BAD_PAGE 5
264#define TAINT_USER 6
265#define TAINT_DIE 7
266#define TAINT_OVERRIDDEN_ACPI_TABLE 8
267#define TAINT_WARN 9
268#define TAINT_CRAP 10
269
270extern void dump_stack(void) __cold;
271
272enum {
273 DUMP_PREFIX_NONE,
274 DUMP_PREFIX_ADDRESS,
275 DUMP_PREFIX_OFFSET
276};
277extern void hex_dump_to_buffer(const void *buf, size_t len,
278 int rowsize, int groupsize,
279 char *linebuf, size_t linebuflen, bool ascii);
280extern void print_hex_dump(const char *level, const char *prefix_str,
281 int prefix_type, int rowsize, int groupsize,
282 const void *buf, size_t len, bool ascii);
283extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
284 const void *buf, size_t len);
285
286extern const char hex_asc[];
287#define hex_asc_lo(x) hex_asc[((x) & 0x0f)]
288#define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4]
289
290static inline char *pack_hex_byte(char *buf, u8 byte)
291{
292 *buf++ = hex_asc_hi(byte);
293 *buf++ = hex_asc_lo(byte);
294 return buf;
295}
296
297#define pr_emerg(fmt, arg...) \
298 printk(KERN_EMERG fmt, ##arg)
299#define pr_alert(fmt, arg...) \
300 printk(KERN_ALERT fmt, ##arg)
301#define pr_crit(fmt, arg...) \
302 printk(KERN_CRIT fmt, ##arg)
303#define pr_err(fmt, arg...) \
304 printk(KERN_ERR fmt, ##arg)
305#define pr_warning(fmt, arg...) \
306 printk(KERN_WARNING fmt, ##arg)
307#define pr_notice(fmt, arg...) \
308 printk(KERN_NOTICE fmt, ##arg)
309#define pr_info(fmt, arg...) \
310 printk(KERN_INFO fmt, ##arg)
311
312/* If you are writing a driver, please use dev_dbg instead */
313#if defined(CONFIG_DYNAMIC_PRINTK_DEBUG)
314#define pr_debug(fmt, ...) do { \
315 dynamic_pr_debug(fmt, ##__VA_ARGS__); \
316 } while (0)
317#elif defined(DEBUG)
318#define pr_debug(fmt, arg...) \
319 printk(KERN_DEBUG fmt, ##arg)
320#else
321#define pr_debug(fmt, arg...) \
322 ({ if (0) printk(KERN_DEBUG fmt, ##arg); 0; })
323#endif
324
325/*
326 * Display an IP address in readable format.
327 */
328
329#define NIPQUAD(addr) \
330 ((unsigned char *)&addr)[0], \
331 ((unsigned char *)&addr)[1], \
332 ((unsigned char *)&addr)[2], \
333 ((unsigned char *)&addr)[3]
334#define NIPQUAD_FMT "%u.%u.%u.%u"
335
336#define NIP6(addr) \
337 ntohs((addr).s6_addr16[0]), \
338 ntohs((addr).s6_addr16[1]), \
339 ntohs((addr).s6_addr16[2]), \
340 ntohs((addr).s6_addr16[3]), \
341 ntohs((addr).s6_addr16[4]), \
342 ntohs((addr).s6_addr16[5]), \
343 ntohs((addr).s6_addr16[6]), \
344 ntohs((addr).s6_addr16[7])
345#define NIP6_FMT "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x"
346#define NIP6_SEQFMT "%04x%04x%04x%04x%04x%04x%04x%04x"
347
348#if defined(__LITTLE_ENDIAN)
349#define HIPQUAD(addr) \
350 ((unsigned char *)&addr)[3], \
351 ((unsigned char *)&addr)[2], \
352 ((unsigned char *)&addr)[1], \
353 ((unsigned char *)&addr)[0]
354#elif defined(__BIG_ENDIAN)
355#define HIPQUAD NIPQUAD
356#else
357#error "Please fix asm/byteorder.h"
358#endif /* __LITTLE_ENDIAN */
359
360/*
361 * min()/max()/clamp() macros that also do
362 * strict type-checking.. See the
363 * "unnecessary" pointer comparison.
364 */
365#define min(x, y) ({ \
366 typeof(x) _min1 = (x); \
367 typeof(y) _min2 = (y); \
368 (void) (&_min1 == &_min2); \
369 _min1 < _min2 ? _min1 : _min2; })
370
371#define max(x, y) ({ \
372 typeof(x) _max1 = (x); \
373 typeof(y) _max2 = (y); \
374 (void) (&_max1 == &_max2); \
375 _max1 > _max2 ? _max1 : _max2; })
376
377/**
378 * clamp - return a value clamped to a given range with strict typechecking
379 * @val: current value
380 * @min: minimum allowable value
381 * @max: maximum allowable value
382 *
383 * This macro does strict typechecking of min/max to make sure they are of the
384 * same type as val. See the unnecessary pointer comparisons.
385 */
386#define clamp(val, min, max) ({ \
387 typeof(val) __val = (val); \
388 typeof(min) __min = (min); \
389 typeof(max) __max = (max); \
390 (void) (&__val == &__min); \
391 (void) (&__val == &__max); \
392 __val = __val < __min ? __min: __val; \
393 __val > __max ? __max: __val; })
394
395/*
396 * ..and if you can't take the strict
397 * types, you can specify one yourself.
398 *
399 * Or not use min/max/clamp at all, of course.
400 */
401#define min_t(type, x, y) ({ \
402 type __min1 = (x); \
403 type __min2 = (y); \
404 __min1 < __min2 ? __min1: __min2; })
405
406#define max_t(type, x, y) ({ \
407 type __max1 = (x); \
408 type __max2 = (y); \
409 __max1 > __max2 ? __max1: __max2; })
410
411/**
412 * clamp_t - return a value clamped to a given range using a given type
413 * @type: the type of variable to use
414 * @val: current value
415 * @min: minimum allowable value
416 * @max: maximum allowable value
417 *
418 * This macro does no typechecking and uses temporary variables of type
419 * 'type' to make all the comparisons.
420 */
421#define clamp_t(type, val, min, max) ({ \
422 type __val = (val); \
423 type __min = (min); \
424 type __max = (max); \
425 __val = __val < __min ? __min: __val; \
426 __val > __max ? __max: __val; })
427
428/**
429 * clamp_val - return a value clamped to a given range using val's type
430 * @val: current value
431 * @min: minimum allowable value
432 * @max: maximum allowable value
433 *
434 * This macro does no typechecking and uses temporary variables of whatever
435 * type the input argument 'val' is. This is useful when val is an unsigned
436 * type and min and max are literals that will otherwise be assigned a signed
437 * integer type.
438 */
439#define clamp_val(val, min, max) ({ \
440 typeof(val) __val = (val); \
441 typeof(val) __min = (min); \
442 typeof(val) __max = (max); \
443 __val = __val < __min ? __min: __val; \
444 __val > __max ? __max: __val; })
445
446/**
447 * container_of - cast a member of a structure out to the containing structure
448 * @ptr: the pointer to the member.
449 * @type: the type of the container struct this is embedded in.
450 * @member: the name of the member within the struct.
451 *
452 */
453#define container_of(ptr, type, member) ({ \
454 const typeof( ((type *)0)->member ) *__mptr = (ptr); \
455 (type *)( (char *)__mptr - offsetof(type,member) );})
456
457struct sysinfo;
458extern int do_sysinfo(struct sysinfo *info);
459
460#endif /* __KERNEL__ */
461
462#define SI_LOAD_SHIFT 16
463struct sysinfo {
464 long uptime; /* Seconds since boot */
465 unsigned long loads[3]; /* 1, 5, and 15 minute load averages */
466 unsigned long totalram; /* Total usable main memory size */
467 unsigned long freeram; /* Available memory size */
468 unsigned long sharedram; /* Amount of shared memory */
469 unsigned long bufferram; /* Memory used by buffers */
470 unsigned long totalswap; /* Total swap space size */
471 unsigned long freeswap; /* swap space still available */
472 unsigned short procs; /* Number of current processes */
473 unsigned short pad; /* explicit padding for m68k */
474 unsigned long totalhigh; /* Total high memory size */
475 unsigned long freehigh; /* Available high memory size */
476 unsigned int mem_unit; /* Memory unit size in bytes */
477 char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */
478};
479
480/* Force a compilation error if condition is true */
481#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
482
483/* Force a compilation error if condition is true, but also produce a
484 result (of value 0 and type size_t), so the expression can be used
485 e.g. in a structure initializer (or where-ever else comma expressions
486 aren't permitted). */
487#define BUILD_BUG_ON_ZERO(e) (sizeof(char[1 - 2 * !!(e)]) - 1)
488
489/* Trap pasters of __FUNCTION__ at compile-time */
490#define __FUNCTION__ (__func__)
491
492/* This helps us to avoid #ifdef CONFIG_NUMA */
493#ifdef CONFIG_NUMA
494#define NUMA_BUILD 1
495#else
496#define NUMA_BUILD 0
497#endif
498
499/* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
500#ifdef CONFIG_FTRACE_MCOUNT_RECORD
501# define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
502#endif
503
504#endif