xref: /linux-6.15/include/linux/kernel.h (revision 4f193362)
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 <asm/byteorder.h>
17 #include <asm/bug.h>
18 
19 extern const char linux_banner[];
20 
21 #define INT_MAX		((int)(~0U>>1))
22 #define INT_MIN		(-INT_MAX - 1)
23 #define UINT_MAX	(~0U)
24 #define LONG_MAX	((long)(~0UL>>1))
25 #define LONG_MIN	(-LONG_MAX - 1)
26 #define ULONG_MAX	(~0UL)
27 
28 #define STACK_MAGIC	0xdeadbeef
29 
30 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
31 #define ALIGN(x,a) (((x)+(a)-1)&~((a)-1))
32 
33 #define	KERN_EMERG	"<0>"	/* system is unusable			*/
34 #define	KERN_ALERT	"<1>"	/* action must be taken immediately	*/
35 #define	KERN_CRIT	"<2>"	/* critical conditions			*/
36 #define	KERN_ERR	"<3>"	/* error conditions			*/
37 #define	KERN_WARNING	"<4>"	/* warning conditions			*/
38 #define	KERN_NOTICE	"<5>"	/* normal but significant condition	*/
39 #define	KERN_INFO	"<6>"	/* informational			*/
40 #define	KERN_DEBUG	"<7>"	/* debug-level messages			*/
41 
42 extern int console_printk[];
43 
44 #define console_loglevel (console_printk[0])
45 #define default_message_loglevel (console_printk[1])
46 #define minimum_console_loglevel (console_printk[2])
47 #define default_console_loglevel (console_printk[3])
48 
49 struct completion;
50 struct pt_regs;
51 struct user;
52 
53 /**
54  * might_sleep - annotation for functions that can sleep
55  *
56  * this macro will print a stack trace if it is executed in an atomic
57  * context (spinlock, irq-handler, ...).
58  *
59  * This is a useful debugging help to be able to catch problems early and not
60  * be biten later when the calling function happens to sleep when it is not
61  * supposed to.
62  */
63 #ifdef CONFIG_PREEMPT_VOLUNTARY
64 extern int cond_resched(void);
65 # define might_resched() cond_resched()
66 #else
67 # define might_resched() do { } while (0)
68 #endif
69 
70 #ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
71   void __might_sleep(char *file, int line);
72 # define might_sleep() \
73 	do { __might_sleep(__FILE__, __LINE__); might_resched(); } while (0)
74 #else
75 # define might_sleep() do { might_resched(); } while (0)
76 #endif
77 
78 #define might_sleep_if(cond) do { if (unlikely(cond)) might_sleep(); } while (0)
79 
80 #define abs(x) ({				\
81 		int __x = (x);			\
82 		(__x < 0) ? -__x : __x;		\
83 	})
84 
85 #define labs(x) ({				\
86 		long __x = (x);			\
87 		(__x < 0) ? -__x : __x;		\
88 	})
89 
90 extern struct notifier_block *panic_notifier_list;
91 extern long (*panic_blink)(long time);
92 NORET_TYPE void panic(const char * fmt, ...)
93 	__attribute__ ((NORET_AND format (printf, 1, 2)));
94 fastcall NORET_TYPE void do_exit(long error_code)
95 	ATTRIB_NORET;
96 NORET_TYPE void complete_and_exit(struct completion *, long)
97 	ATTRIB_NORET;
98 extern unsigned long simple_strtoul(const char *,char **,unsigned int);
99 extern long simple_strtol(const char *,char **,unsigned int);
100 extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
101 extern long long simple_strtoll(const char *,char **,unsigned int);
102 extern int sprintf(char * buf, const char * fmt, ...)
103 	__attribute__ ((format (printf, 2, 3)));
104 extern int vsprintf(char *buf, const char *, va_list)
105 	__attribute__ ((format (printf, 2, 0)));
106 extern int snprintf(char * buf, size_t size, const char * fmt, ...)
107 	__attribute__ ((format (printf, 3, 4)));
108 extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
109 	__attribute__ ((format (printf, 3, 0)));
110 extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
111 	__attribute__ ((format (printf, 3, 4)));
112 extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
113 	__attribute__ ((format (printf, 3, 0)));
114 
115 extern int sscanf(const char *, const char *, ...)
116 	__attribute__ ((format (scanf, 2, 3)));
117 extern int vsscanf(const char *, const char *, va_list)
118 	__attribute__ ((format (scanf, 2, 0)));
119 
120 extern int get_option(char **str, int *pint);
121 extern char *get_options(const char *str, int nints, int *ints);
122 extern unsigned long long memparse(char *ptr, char **retptr);
123 
124 extern int __kernel_text_address(unsigned long addr);
125 extern int kernel_text_address(unsigned long addr);
126 extern int session_of_pgrp(int pgrp);
127 
128 extern void dump_thread(struct pt_regs *regs, struct user *dump);
129 
130 #ifdef CONFIG_PRINTK
131 asmlinkage int vprintk(const char *fmt, va_list args)
132 	__attribute__ ((format (printf, 1, 0)));
133 asmlinkage int printk(const char * fmt, ...)
134 	__attribute__ ((format (printf, 1, 2)));
135 #else
136 static inline int vprintk(const char *s, va_list args)
137 	__attribute__ ((format (printf, 1, 0)));
138 static inline int vprintk(const char *s, va_list args) { return 0; }
139 static inline int printk(const char *s, ...)
140 	__attribute__ ((format (printf, 1, 2)));
141 static inline int printk(const char *s, ...) { return 0; }
142 #endif
143 
144 unsigned long int_sqrt(unsigned long);
145 
146 static inline int __attribute_pure__ long_log2(unsigned long x)
147 {
148 	int r = 0;
149 	for (x >>= 1; x > 0; x >>= 1)
150 		r++;
151 	return r;
152 }
153 
154 static inline unsigned long __attribute_const__ roundup_pow_of_two(unsigned long x)
155 {
156 	return (1UL << fls(x - 1));
157 }
158 
159 extern int printk_ratelimit(void);
160 extern int __printk_ratelimit(int ratelimit_jiffies, int ratelimit_burst);
161 
162 static inline void console_silent(void)
163 {
164 	console_loglevel = 0;
165 }
166 
167 static inline void console_verbose(void)
168 {
169 	if (console_loglevel)
170 		console_loglevel = 15;
171 }
172 
173 extern void bust_spinlocks(int yes);
174 extern int oops_in_progress;		/* If set, an oops, panic(), BUG() or die() is in progress */
175 extern __deprecated_for_modules int panic_timeout;
176 extern int panic_on_oops;
177 extern int tainted;
178 extern const char *print_tainted(void);
179 extern void add_taint(unsigned);
180 
181 /* Values used for system_state */
182 extern enum system_states {
183 	SYSTEM_BOOTING,
184 	SYSTEM_RUNNING,
185 	SYSTEM_HALT,
186 	SYSTEM_POWER_OFF,
187 	SYSTEM_RESTART,
188 	SYSTEM_SUSPEND_DISK,
189 } system_state;
190 
191 #define TAINT_PROPRIETARY_MODULE	(1<<0)
192 #define TAINT_FORCED_MODULE		(1<<1)
193 #define TAINT_UNSAFE_SMP		(1<<2)
194 #define TAINT_FORCED_RMMOD		(1<<3)
195 #define TAINT_MACHINE_CHECK		(1<<4)
196 #define TAINT_BAD_PAGE			(1<<5)
197 
198 extern void dump_stack(void);
199 
200 #ifdef DEBUG
201 #define pr_debug(fmt,arg...) \
202 	printk(KERN_DEBUG fmt,##arg)
203 #else
204 #define pr_debug(fmt,arg...) \
205 	do { } while (0)
206 #endif
207 
208 #define pr_info(fmt,arg...) \
209 	printk(KERN_INFO fmt,##arg)
210 
211 /*
212  *      Display an IP address in readable format.
213  */
214 
215 #define NIPQUAD(addr) \
216 	((unsigned char *)&addr)[0], \
217 	((unsigned char *)&addr)[1], \
218 	((unsigned char *)&addr)[2], \
219 	((unsigned char *)&addr)[3]
220 #define NIPQUAD_FMT "%u.%u.%u.%u"
221 
222 #define NIP6(addr) \
223 	ntohs((addr).s6_addr16[0]), \
224 	ntohs((addr).s6_addr16[1]), \
225 	ntohs((addr).s6_addr16[2]), \
226 	ntohs((addr).s6_addr16[3]), \
227 	ntohs((addr).s6_addr16[4]), \
228 	ntohs((addr).s6_addr16[5]), \
229 	ntohs((addr).s6_addr16[6]), \
230 	ntohs((addr).s6_addr16[7])
231 #define NIP6_FMT "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x"
232 #define NIP6_SEQFMT "%04x%04x%04x%04x%04x%04x%04x%04x"
233 
234 #if defined(__LITTLE_ENDIAN)
235 #define HIPQUAD(addr) \
236 	((unsigned char *)&addr)[3], \
237 	((unsigned char *)&addr)[2], \
238 	((unsigned char *)&addr)[1], \
239 	((unsigned char *)&addr)[0]
240 #elif defined(__BIG_ENDIAN)
241 #define HIPQUAD	NIPQUAD
242 #else
243 #error "Please fix asm/byteorder.h"
244 #endif /* __LITTLE_ENDIAN */
245 
246 /*
247  * min()/max() macros that also do
248  * strict type-checking.. See the
249  * "unnecessary" pointer comparison.
250  */
251 #define min(x,y) ({ \
252 	typeof(x) _x = (x);	\
253 	typeof(y) _y = (y);	\
254 	(void) (&_x == &_y);		\
255 	_x < _y ? _x : _y; })
256 
257 #define max(x,y) ({ \
258 	typeof(x) _x = (x);	\
259 	typeof(y) _y = (y);	\
260 	(void) (&_x == &_y);		\
261 	_x > _y ? _x : _y; })
262 
263 /*
264  * ..and if you can't take the strict
265  * types, you can specify one yourself.
266  *
267  * Or not use min/max at all, of course.
268  */
269 #define min_t(type,x,y) \
270 	({ type __x = (x); type __y = (y); __x < __y ? __x: __y; })
271 #define max_t(type,x,y) \
272 	({ type __x = (x); type __y = (y); __x > __y ? __x: __y; })
273 
274 
275 /**
276  * container_of - cast a member of a structure out to the containing structure
277  * @ptr:	the pointer to the member.
278  * @type:	the type of the container struct this is embedded in.
279  * @member:	the name of the member within the struct.
280  *
281  */
282 #define container_of(ptr, type, member) ({			\
283         const typeof( ((type *)0)->member ) *__mptr = (ptr);	\
284         (type *)( (char *)__mptr - offsetof(type,member) );})
285 
286 /*
287  * Check at compile time that something is of a particular type.
288  * Always evaluates to 1 so you may use it easily in comparisons.
289  */
290 #define typecheck(type,x) \
291 ({	type __dummy; \
292 	typeof(x) __dummy2; \
293 	(void)(&__dummy == &__dummy2); \
294 	1; \
295 })
296 
297 /*
298  * Check at compile time that 'function' is a certain type, or is a pointer
299  * to that type (needs to use typedef for the function type.)
300  */
301 #define typecheck_fn(type,function) \
302 ({	typeof(type) __tmp = function; \
303 	(void)__tmp; \
304 })
305 
306 #endif /* __KERNEL__ */
307 
308 #define SI_LOAD_SHIFT	16
309 struct sysinfo {
310 	long uptime;			/* Seconds since boot */
311 	unsigned long loads[3];		/* 1, 5, and 15 minute load averages */
312 	unsigned long totalram;		/* Total usable main memory size */
313 	unsigned long freeram;		/* Available memory size */
314 	unsigned long sharedram;	/* Amount of shared memory */
315 	unsigned long bufferram;	/* Memory used by buffers */
316 	unsigned long totalswap;	/* Total swap space size */
317 	unsigned long freeswap;		/* swap space still available */
318 	unsigned short procs;		/* Number of current processes */
319 	unsigned short pad;		/* explicit padding for m68k */
320 	unsigned long totalhigh;	/* Total high memory size */
321 	unsigned long freehigh;		/* Available high memory size */
322 	unsigned int mem_unit;		/* Memory unit size in bytes */
323 	char _f[20-2*sizeof(long)-sizeof(int)];	/* Padding: libc5 uses this.. */
324 };
325 
326 /* Force a compilation error if condition is true */
327 #define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
328 
329 /* Trap pasters of __FUNCTION__ at compile-time */
330 #define __FUNCTION__ (__func__)
331 
332 #endif
333