xref: /linux-6.15/include/linux/kernel.h (revision de2fe5e0)
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 atomic_notifier_head 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 extern void oops_enter(void);
95 extern void oops_exit(void);
96 extern int oops_may_print(void);
97 fastcall NORET_TYPE void do_exit(long error_code)
98 	ATTRIB_NORET;
99 NORET_TYPE void complete_and_exit(struct completion *, long)
100 	ATTRIB_NORET;
101 extern unsigned long simple_strtoul(const char *,char **,unsigned int);
102 extern long simple_strtol(const char *,char **,unsigned int);
103 extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
104 extern long long simple_strtoll(const char *,char **,unsigned int);
105 extern int sprintf(char * buf, const char * fmt, ...)
106 	__attribute__ ((format (printf, 2, 3)));
107 extern int vsprintf(char *buf, const char *, va_list)
108 	__attribute__ ((format (printf, 2, 0)));
109 extern int snprintf(char * buf, size_t size, const char * fmt, ...)
110 	__attribute__ ((format (printf, 3, 4)));
111 extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
112 	__attribute__ ((format (printf, 3, 0)));
113 extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
114 	__attribute__ ((format (printf, 3, 4)));
115 extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
116 	__attribute__ ((format (printf, 3, 0)));
117 
118 extern int sscanf(const char *, const char *, ...)
119 	__attribute__ ((format (scanf, 2, 3)));
120 extern int vsscanf(const char *, const char *, va_list)
121 	__attribute__ ((format (scanf, 2, 0)));
122 
123 extern int get_option(char **str, int *pint);
124 extern char *get_options(const char *str, int nints, int *ints);
125 extern unsigned long long memparse(char *ptr, char **retptr);
126 
127 extern int __kernel_text_address(unsigned long addr);
128 extern int kernel_text_address(unsigned long addr);
129 extern int session_of_pgrp(int pgrp);
130 
131 extern void dump_thread(struct pt_regs *regs, struct user *dump);
132 
133 #ifdef CONFIG_PRINTK
134 asmlinkage int vprintk(const char *fmt, va_list args)
135 	__attribute__ ((format (printf, 1, 0)));
136 asmlinkage int printk(const char * fmt, ...)
137 	__attribute__ ((format (printf, 1, 2)));
138 #else
139 static inline int vprintk(const char *s, va_list args)
140 	__attribute__ ((format (printf, 1, 0)));
141 static inline int vprintk(const char *s, va_list args) { return 0; }
142 static inline int printk(const char *s, ...)
143 	__attribute__ ((format (printf, 1, 2)));
144 static inline int printk(const char *s, ...) { return 0; }
145 #endif
146 
147 unsigned long int_sqrt(unsigned long);
148 
149 static inline int __attribute_pure__ long_log2(unsigned long x)
150 {
151 	int r = 0;
152 	for (x >>= 1; x > 0; x >>= 1)
153 		r++;
154 	return r;
155 }
156 
157 static inline unsigned long
158 __attribute_const__ roundup_pow_of_two(unsigned long x)
159 {
160 	return 1UL << fls_long(x - 1);
161 }
162 
163 extern int printk_ratelimit(void);
164 extern int __printk_ratelimit(int ratelimit_jiffies, int ratelimit_burst);
165 
166 static inline void console_silent(void)
167 {
168 	console_loglevel = 0;
169 }
170 
171 static inline void console_verbose(void)
172 {
173 	if (console_loglevel)
174 		console_loglevel = 15;
175 }
176 
177 extern void bust_spinlocks(int yes);
178 extern int oops_in_progress;		/* If set, an oops, panic(), BUG() or die() is in progress */
179 extern __deprecated_for_modules int panic_timeout;
180 extern int panic_on_oops;
181 extern int tainted;
182 extern const char *print_tainted(void);
183 extern void add_taint(unsigned);
184 
185 /* Values used for system_state */
186 extern enum system_states {
187 	SYSTEM_BOOTING,
188 	SYSTEM_RUNNING,
189 	SYSTEM_HALT,
190 	SYSTEM_POWER_OFF,
191 	SYSTEM_RESTART,
192 	SYSTEM_SUSPEND_DISK,
193 } system_state;
194 
195 #define TAINT_PROPRIETARY_MODULE	(1<<0)
196 #define TAINT_FORCED_MODULE		(1<<1)
197 #define TAINT_UNSAFE_SMP		(1<<2)
198 #define TAINT_FORCED_RMMOD		(1<<3)
199 #define TAINT_MACHINE_CHECK		(1<<4)
200 #define TAINT_BAD_PAGE			(1<<5)
201 
202 extern void dump_stack(void);
203 
204 #ifdef DEBUG
205 #define pr_debug(fmt,arg...) \
206 	printk(KERN_DEBUG fmt,##arg)
207 #else
208 #define pr_debug(fmt,arg...) \
209 	do { } while (0)
210 #endif
211 
212 #define pr_info(fmt,arg...) \
213 	printk(KERN_INFO fmt,##arg)
214 
215 /*
216  *      Display an IP address in readable format.
217  */
218 
219 #define NIPQUAD(addr) \
220 	((unsigned char *)&addr)[0], \
221 	((unsigned char *)&addr)[1], \
222 	((unsigned char *)&addr)[2], \
223 	((unsigned char *)&addr)[3]
224 #define NIPQUAD_FMT "%u.%u.%u.%u"
225 
226 #define NIP6(addr) \
227 	ntohs((addr).s6_addr16[0]), \
228 	ntohs((addr).s6_addr16[1]), \
229 	ntohs((addr).s6_addr16[2]), \
230 	ntohs((addr).s6_addr16[3]), \
231 	ntohs((addr).s6_addr16[4]), \
232 	ntohs((addr).s6_addr16[5]), \
233 	ntohs((addr).s6_addr16[6]), \
234 	ntohs((addr).s6_addr16[7])
235 #define NIP6_FMT "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x"
236 #define NIP6_SEQFMT "%04x%04x%04x%04x%04x%04x%04x%04x"
237 
238 #if defined(__LITTLE_ENDIAN)
239 #define HIPQUAD(addr) \
240 	((unsigned char *)&addr)[3], \
241 	((unsigned char *)&addr)[2], \
242 	((unsigned char *)&addr)[1], \
243 	((unsigned char *)&addr)[0]
244 #elif defined(__BIG_ENDIAN)
245 #define HIPQUAD	NIPQUAD
246 #else
247 #error "Please fix asm/byteorder.h"
248 #endif /* __LITTLE_ENDIAN */
249 
250 /*
251  * min()/max() macros that also do
252  * strict type-checking.. See the
253  * "unnecessary" pointer comparison.
254  */
255 #define min(x,y) ({ \
256 	typeof(x) _x = (x);	\
257 	typeof(y) _y = (y);	\
258 	(void) (&_x == &_y);		\
259 	_x < _y ? _x : _y; })
260 
261 #define max(x,y) ({ \
262 	typeof(x) _x = (x);	\
263 	typeof(y) _y = (y);	\
264 	(void) (&_x == &_y);		\
265 	_x > _y ? _x : _y; })
266 
267 /*
268  * ..and if you can't take the strict
269  * types, you can specify one yourself.
270  *
271  * Or not use min/max at all, of course.
272  */
273 #define min_t(type,x,y) \
274 	({ type __x = (x); type __y = (y); __x < __y ? __x: __y; })
275 #define max_t(type,x,y) \
276 	({ type __x = (x); type __y = (y); __x > __y ? __x: __y; })
277 
278 
279 /**
280  * container_of - cast a member of a structure out to the containing structure
281  * @ptr:	the pointer to the member.
282  * @type:	the type of the container struct this is embedded in.
283  * @member:	the name of the member within the struct.
284  *
285  */
286 #define container_of(ptr, type, member) ({			\
287         const typeof( ((type *)0)->member ) *__mptr = (ptr);	\
288         (type *)( (char *)__mptr - offsetof(type,member) );})
289 
290 /*
291  * Check at compile time that something is of a particular type.
292  * Always evaluates to 1 so you may use it easily in comparisons.
293  */
294 #define typecheck(type,x) \
295 ({	type __dummy; \
296 	typeof(x) __dummy2; \
297 	(void)(&__dummy == &__dummy2); \
298 	1; \
299 })
300 
301 /*
302  * Check at compile time that 'function' is a certain type, or is a pointer
303  * to that type (needs to use typedef for the function type.)
304  */
305 #define typecheck_fn(type,function) \
306 ({	typeof(type) __tmp = function; \
307 	(void)__tmp; \
308 })
309 
310 #endif /* __KERNEL__ */
311 
312 #define SI_LOAD_SHIFT	16
313 struct sysinfo {
314 	long uptime;			/* Seconds since boot */
315 	unsigned long loads[3];		/* 1, 5, and 15 minute load averages */
316 	unsigned long totalram;		/* Total usable main memory size */
317 	unsigned long freeram;		/* Available memory size */
318 	unsigned long sharedram;	/* Amount of shared memory */
319 	unsigned long bufferram;	/* Memory used by buffers */
320 	unsigned long totalswap;	/* Total swap space size */
321 	unsigned long freeswap;		/* swap space still available */
322 	unsigned short procs;		/* Number of current processes */
323 	unsigned short pad;		/* explicit padding for m68k */
324 	unsigned long totalhigh;	/* Total high memory size */
325 	unsigned long freehigh;		/* Available high memory size */
326 	unsigned int mem_unit;		/* Memory unit size in bytes */
327 	char _f[20-2*sizeof(long)-sizeof(int)];	/* Padding: libc5 uses this.. */
328 };
329 
330 /* Force a compilation error if condition is true */
331 #define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
332 
333 /* Trap pasters of __FUNCTION__ at compile-time */
334 #define __FUNCTION__ (__func__)
335 
336 #endif
337