summaryrefslogtreecommitdiff
path: root/include/linux/kernel.h
blob: 94d17ff64c5a3b48c0f6716d29b9832d6a896551 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
#ifndef _LINUX_KERNEL_H
#define _LINUX_KERNEL_H

/*
 * 'kernel.h' contains some often-used function prototypes etc
 */

#ifdef __KERNEL__

#include <stdarg.h>
#include <linux/linkage.h>
#include <linux/stddef.h>
#include <linux/types.h>
#include <linux/compiler.h>
#include <linux/bitops.h>
#include <linux/log2.h>
#include <linux/typecheck.h>
#include <linux/ratelimit.h>
#include <linux/dynamic_printk.h>
#include <asm/byteorder.h>
#include <asm/bug.h>

extern const char linux_banner[];
extern const char linux_proc_banner[];

#define USHORT_MAX	((u16)(~0U))
#define SHORT_MAX	((s16)(USHORT_MAX>>1))
#define SHORT_MIN	(-SHORT_MAX - 1)
#define INT_MAX		((int)(~0U>>1))
#define INT_MIN		(-INT_MAX - 1)
#define UINT_MAX	(~0U)
#define LONG_MAX	((long)(~0UL>>1))
#define LONG_MIN	(-LONG_MAX - 1)
#define ULONG_MAX	(~0UL)
#define LLONG_MAX	((long long)(~0ULL>>1))
#define LLONG_MIN	(-LLONG_MAX - 1)
#define ULLONG_MAX	(~0ULL)

#define STACK_MAGIC	0xdeadbeef

#define ALIGN(x,a)		__ALIGN_MASK(x,(typeof(x))(a)-1)
#define __ALIGN_MASK(x,mask)	(((x)+(mask))&~(mask))
#define PTR_ALIGN(p, a)		((typeof(p))ALIGN((unsigned long)(p), (a)))
#define IS_ALIGNED(x, a)		(((x) & ((typeof(x))(a) - 1)) == 0)

#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))

#define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
#define roundup(x, y) ((((x) + ((y) - 1)) / (y)) * (y))

#define _RET_IP_		(unsigned long)__builtin_return_address(0)
#define _THIS_IP_  ({ __label__ __here; __here: (unsigned long)&&__here; })

#ifdef CONFIG_LBD
# include <asm/div64.h>
# define sector_div(a, b) do_div(a, b)
#else
# define sector_div(n, b)( \
{ \
	int _res; \
	_res = (n) % (b); \
	(n) /= (b); \
	_res; \
} \
)
#endif

/**
 * upper_32_bits - return bits 32-63 of a number
 * @n: the number we're accessing
 *
 * A basic shift-right of a 64- or 32-bit quantity.  Use this to suppress
 * the "right shift count >= width of type" warning when that quantity is
 * 32-bits.
 */
#define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))

/**
 * lower_32_bits - return bits 0-31 of a number
 * @n: the number we're accessing
 */
#define lower_32_bits(n) ((u32)(n))

#define	KERN_EMERG	"<0>"	/* system is unusable			*/
#define	KERN_ALERT	"<1>"	/* action must be taken immediately	*/
#define	KERN_CRIT	"<2>"	/* critical conditions			*/
#define	KERN_ERR	"<3>"	/* error conditions			*/
#define	KERN_WARNING	"<4>"	/* warning conditions			*/
#define	KERN_NOTICE	"<5>"	/* normal but significant condition	*/
#define	KERN_INFO	"<6>"	/* informational			*/
#define	KERN_DEBUG	"<7>"	/* debug-level messages			*/

/*
 * Annotation for a "continued" line of log printout (only done after a
 * line that had no enclosing \n). Only to be used by core/arch code
 * during early bootup (a continued line is not SMP-safe otherwise).
 */
#define	KERN_CONT	""

extern int console_printk[];

#define console_loglevel (console_printk[0])
#define default_message_loglevel (console_printk[1])
#define minimum_console_loglevel (console_printk[2])
#define default_console_loglevel (console_printk[3])

struct completion;
struct pt_regs;
struct user;

#ifdef CONFIG_PREEMPT_VOLUNTARY
extern int _cond_resched(void);
# define might_resched() _cond_resched()
#else
# define might_resched() do { } while (0)
#endif

/**
 * might_sleep - annotation for functions that can sleep
 *
 * this macro will print a stack trace if it is executed in an atomic
 * context (spinlock, irq-handler, ...).
 *
 * This is a useful debugging help to be able to catch problems early and not
 * be bitten later when the calling function happens to sleep when it is not
 * supposed to.
 */
#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
  void __might_sleep(char *file, int line);
# define might_sleep() \
	do { __might_sleep(__FILE__, __LINE__); might_resched(); } while (0)
#else
# define might_sleep() do { might_resched(); } while (0)
#endif

#define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)

#define abs(x) ({				\
		int __x = (x);			\
		(__x < 0) ? -__x : __x;		\
	})

extern struct atomic_notifier_head panic_notifier_list;
extern long (*panic_blink)(long time);
NORET_TYPE void panic(const char * fmt, ...)
	__attribute__ ((NORET_AND format (printf, 1, 2))) __cold;
extern void oops_enter(void);
extern void oops_exit(void);
extern int oops_may_print(void);
NORET_TYPE void do_exit(long error_code)
	ATTRIB_NORET;
NORET_TYPE void complete_and_exit(struct completion *, long)
	ATTRIB_NORET;
extern unsigned long simple_strtoul(const char *,char **,unsigned int);
extern long simple_strtol(const char *,char **,unsigned int);
extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
extern long long simple_strtoll(const char *,char **,unsigned int);
extern int strict_strtoul(const char *, unsigned int, unsigned long *);
extern int strict_strtol(const char *, unsigned int, long *);
extern int strict_strtoull(const char *, unsigned int, unsigned long long *);
extern int strict_strtoll(const char *, unsigned int, long long *);
extern int sprintf(char * buf, const char * fmt, ...)
	__attribute__ ((format (printf, 2, 3)));
extern int vsprintf(char *buf, const char *, va_list)
	__attribute__ ((format (printf, 2, 0)));
extern int snprintf(char * buf, size_t size, const char * fmt, ...)
	__attribute__ ((format (printf, 3, 4)));
extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
	__attribute__ ((format (printf, 3, 0)));
extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
	__attribute__ ((format (printf, 3, 4)));
extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
	__attribute__ ((format (printf, 3, 0)));
extern char *kasprintf(gfp_t gfp, const char *fmt, ...)
	__attribute__ ((format (printf, 2, 3)));
extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args);

extern int sscanf(const char *, const char *, ...)
	__attribute__ ((format (scanf, 2, 3)));
extern int vsscanf(const char *, const char *, va_list)
	__attribute__ ((format (scanf, 2, 0)));

extern int get_option(char **str, int *pint);
extern char *get_options(const char *str, int nints, int *ints);
extern unsigned long long memparse(const char *ptr, char **retptr);

extern int core_kernel_text(unsigned long addr);
extern int __kernel_text_address(unsigned long addr);
extern int kernel_text_address(unsigned long addr);
struct pid;
extern struct pid *session_of_pgrp(struct pid *pgrp);

#ifdef CONFIG_PRINTK
asmlinkage int vprintk(const char *fmt, va_list args)
	__attribute__ ((format (printf, 1, 0)));
asmlinkage int printk(const char * fmt, ...)
	__attribute__ ((format (printf, 1, 2))) __cold;

extern struct ratelimit_state printk_ratelimit_state;
extern int printk_ratelimit(void);
extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
				   unsigned int interval_msec);
#else
static inline int vprintk(const char *s, va_list args)
	__attribute__ ((format (printf, 1, 0)));
static inline int vprintk(const char *s, va_list args) { return 0; }
static inline int printk(const char *s, ...)
	__attribute__ ((format (printf, 1, 2)));
static inline int __cold printk(const char *s, ...) { return 0; }
static inline int printk_ratelimit(void) { return 0; }
static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies, \
					  unsigned int interval_msec)	\
		{ return false; }
#endif

extern int printk_needs_cpu(int cpu);
extern void printk_tick(void);

extern void asmlinkage __attribute__((format(printf, 1, 2)))
	early_printk(const char *fmt, ...);

unsigned long int_sqrt(unsigned long);

static inline void console_silent(void)
{
	console_loglevel = 0;
}

static inline void console_verbose(void)
{
	if (console_loglevel)
		console_loglevel = 15;
}

extern void bust_spinlocks(int yes);
extern void wake_up_klogd(void);
extern int oops_in_progress;		/* If set, an oops, panic(), BUG() or die() is in progress */
extern int panic_timeout;
extern int panic_on_oops;
extern int panic_on_unrecovered_nmi;
extern const char *print_tainted(void);
extern void add_taint(unsigned flag);
extern int test_taint(unsigned flag);
extern unsigned long get_taint(void);
extern int root_mountflags;

/* Values used for system_state */
extern enum system_states {
	SYSTEM_BOOTING,
	SYSTEM_RUNNING,
	SYSTEM_HALT,
	SYSTEM_POWER_OFF,
	SYSTEM_RESTART,
	SYSTEM_SUSPEND_DISK,
} system_state;

#define TAINT_PROPRIETARY_MODULE	0
#define TAINT_FORCED_MODULE		1
#define TAINT_UNSAFE_SMP		2
#define TAINT_FORCED_RMMOD		3
#define TAINT_MACHINE_CHECK		4
#define TAINT_BAD_PAGE			5
#define TAINT_USER			6
#define TAINT_DIE			7
#define TAINT_OVERRIDDEN_ACPI_TABLE	8
#define TAINT_WARN			9
#define TAINT_CRAP			10

extern void dump_stack(void) __cold;

enum {
	DUMP_PREFIX_NONE,
	DUMP_PREFIX_ADDRESS,
	DUMP_PREFIX_OFFSET
};
extern void hex_dump_to_buffer(const void *buf, size_t len,
				int rowsize, int groupsize,
				char *linebuf, size_t linebuflen, bool ascii);
extern void print_hex_dump(const char *level, const char *prefix_str,
				int prefix_type, int rowsize, int groupsize,
				const void *buf, size_t len, bool ascii);
extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
			const void *buf, size_t len);

extern const char hex_asc[];
#define hex_asc_lo(x)	hex_asc[((x) & 0x0f)]
#define hex_asc_hi(x)	hex_asc[((x) & 0xf0) >> 4]

static inline char *pack_hex_byte(char *buf, u8 byte)
{
	*buf++ = hex_asc_hi(byte);
	*buf++ = hex_asc_lo(byte);
	return buf;
}

#define pr_emerg(fmt, arg...) \
	printk(KERN_EMERG fmt, ##arg)
#define pr_alert(fmt, arg...) \
	printk(KERN_ALERT fmt, ##arg)
#define pr_crit(fmt, arg...) \
	printk(KERN_CRIT fmt, ##arg)
#define pr_err(fmt, arg...) \
	printk(KERN_ERR fmt, ##arg)
#define pr_warning(fmt, arg...) \
	printk(KERN_WARNING fmt, ##arg)
#define pr_notice(fmt, arg...) \
	printk(KERN_NOTICE fmt, ##arg)
#define pr_info(fmt, arg...) \
	printk(KERN_INFO fmt, ##arg)

/* If you are writing a driver, please use dev_dbg instead */
#if defined(CONFIG_DYNAMIC_PRINTK_DEBUG)
#define pr_debug(fmt, ...) do { \
	dynamic_pr_debug(fmt, ##__VA_ARGS__); \
	} while (0)
#elif defined(DEBUG)
#define pr_debug(fmt, arg...) \
	printk(KERN_DEBUG fmt, ##arg)
#else
#define pr_debug(fmt, arg...) \
	({ if (0) printk(KERN_DEBUG fmt, ##arg); 0; })
#endif

/*
 *      Display an IP address in readable format.
 */

#define NIPQUAD(addr) \
	((unsigned char *)&addr)[0], \
	((unsigned char *)&addr)[1], \
	((unsigned char *)&addr)[2], \
	((unsigned char *)&addr)[3]
#define NIPQUAD_FMT "%u.%u.%u.%u"

#define NIP6(addr) \
	ntohs((addr).s6_addr16[0]), \
	ntohs((addr).s6_addr16[1]), \
	ntohs((addr).s6_addr16[2]), \
	ntohs((addr).s6_addr16[3]), \
	ntohs((addr).s6_addr16[4]), \
	ntohs((addr).s6_addr16[5]), \
	ntohs((addr).s6_addr16[6]), \
	ntohs((addr).s6_addr16[7])
#define NIP6_FMT "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x"
#define NIP6_SEQFMT "%04x%04x%04x%04x%04x%04x%04x%04x"

#if defined(__LITTLE_ENDIAN)
#define HIPQUAD(addr) \
	((unsigned char *)&addr)[3], \
	((unsigned char *)&addr)[2], \
	((unsigned char *)&addr)[1], \
	((unsigned char *)&addr)[0]
#elif defined(__BIG_ENDIAN)
#define HIPQUAD	NIPQUAD
#else
#error "Please fix asm/byteorder.h"
#endif /* __LITTLE_ENDIAN */

/*
 * min()/max()/clamp() macros that also do
 * strict type-checking.. See the
 * "unnecessary" pointer comparison.
 */
#define min(x, y) ({				\
	typeof(x) _min1 = (x);			\
	typeof(y) _min2 = (y);			\
	(void) (&_min1 == &_min2);		\
	_min1 < _min2 ? _min1 : _min2; })

#define max(x, y) ({				\
	typeof(x) _max1 = (x);			\
	typeof(y) _max2 = (y);			\
	(void) (&_max1 == &_max2);		\
	_max1 > _max2 ? _max1 : _max2; })

/**
 * clamp - return a value clamped to a given range with strict typechecking
 * @val: current value
 * @min: minimum allowable value
 * @max: maximum allowable value
 *
 * This macro does strict typechecking of min/max to make sure they are of the
 * same type as val.  See the unnecessary pointer comparisons.
 */
#define clamp(val, min, max) ({			\
	typeof(val) __val = (val);		\
	typeof(min) __min = (min);		\
	typeof(max) __max = (max);		\
	(void) (&__val == &__min);		\
	(void) (&__val == &__max);		\
	__val = __val < __min ? __min: __val;	\
	__val > __max ? __max: __val; })

/*
 * ..and if you can't take the strict
 * types, you can specify one yourself.
 *
 * Or not use min/max/clamp at all, of course.
 */
#define min_t(type, x, y) ({			\
	type __min1 = (x);			\
	type __min2 = (y);			\
	__min1 < __min2 ? __min1: __min2; })

#define max_t(type, x, y) ({			\
	type __max1 = (x);			\
	type __max2 = (y);			\
	__max1 > __max2 ? __max1: __max2; })

/**
 * clamp_t - return a value clamped to a given range using a given type
 * @type: the type of variable to use
 * @val: current value
 * @min: minimum allowable value
 * @max: maximum allowable value
 *
 * This macro does no typechecking and uses temporary variables of type
 * 'type' to make all the comparisons.
 */
#define clamp_t(type, val, min, max) ({		\
	type __val = (val);			\
	type __min = (min);			\
	type __max = (max);			\
	__val = __val < __min ? __min: __val;	\
	__val > __max ? __max: __val; })

/**
 * clamp_val - return a value clamped to a given range using val's type
 * @val: current value
 * @min: minimum allowable value
 * @max: maximum allowable value
 *
 * This macro does no typechecking and uses temporary variables of whatever
 * type the input argument 'val' is.  This is useful when val is an unsigned
 * type and min and max are literals that will otherwise be assigned a signed
 * integer type.
 */
#define clamp_val(val, min, max) ({		\
	typeof(val) __val = (val);		\
	typeof(val) __min = (min);		\
	typeof(val) __max = (max);		\
	__val = __val < __min ? __min: __val;	\
	__val > __max ? __max: __val; })

/**
 * container_of - cast a member of a structure out to the containing structure
 * @ptr:	the pointer to the member.
 * @type:	the type of the container struct this is embedded in.
 * @member:	the name of the member within the struct.
 *
 */
#define container_of(ptr, type, member) ({			\
	const typeof( ((type *)0)->member ) *__mptr = (ptr);	\
	(type *)( (char *)__mptr - offsetof(type,member) );})

struct sysinfo;
extern int do_sysinfo(struct sysinfo *info);

#endif /* __KERNEL__ */

#define SI_LOAD_SHIFT	16
struct sysinfo {
	long uptime;			/* Seconds since boot */
	unsigned long loads[3];		/* 1, 5, and 15 minute load averages */
	unsigned long totalram;		/* Total usable main memory size */
	unsigned long freeram;		/* Available memory size */
	unsigned long sharedram;	/* Amount of shared memory */
	unsigned long bufferram;	/* Memory used by buffers */
	unsigned long totalswap;	/* Total swap space size */
	unsigned long freeswap;		/* swap space still available */
	unsigned short procs;		/* Number of current processes */
	unsigned short pad;		/* explicit padding for m68k */
	unsigned long totalhigh;	/* Total high memory size */
	unsigned long freehigh;		/* Available high memory size */
	unsigned int mem_unit;		/* Memory unit size in bytes */
	char _f[20-2*sizeof(long)-sizeof(int)];	/* Padding: libc5 uses this.. */
};

/* Force a compilation error if condition is true */
#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))

/* Force a compilation error if condition is true, but also produce a
   result (of value 0 and type size_t), so the expression can be used
   e.g. in a structure initializer (or where-ever else comma expressions
   aren't permitted). */
#define BUILD_BUG_ON_ZERO(e) (sizeof(char[1 - 2 * !!(e)]) - 1)

/* Trap pasters of __FUNCTION__ at compile-time */
#define __FUNCTION__ (__func__)

/* This helps us to avoid #ifdef CONFIG_NUMA */
#ifdef CONFIG_NUMA
#define NUMA_BUILD 1
#else
#define NUMA_BUILD 0
#endif

/* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
#ifdef CONFIG_FTRACE_MCOUNT_RECORD
# define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
#endif

#endif