kernel.h 22 KB

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  1. #ifndef _LINUX_KERNEL_H
  2. #define _LINUX_KERNEL_H
  3. /*
  4. * 'kernel.h' contains some often-used function prototypes etc
  5. */
  6. #ifdef __KERNEL__
  7. #include <stdarg.h>
  8. #include <linux/linkage.h>
  9. #include <linux/stddef.h>
  10. #include <linux/types.h>
  11. #include <linux/compiler.h>
  12. #include <linux/bitops.h>
  13. #include <linux/log2.h>
  14. #include <linux/typecheck.h>
  15. #include <linux/dynamic_debug.h>
  16. #include <asm/byteorder.h>
  17. #include <asm/bug.h>
  18. extern const char linux_banner[];
  19. extern const char linux_proc_banner[];
  20. #define USHORT_MAX ((u16)(~0U))
  21. #define SHORT_MAX ((s16)(USHORT_MAX>>1))
  22. #define SHORT_MIN (-SHORT_MAX - 1)
  23. #define INT_MAX ((int)(~0U>>1))
  24. #define INT_MIN (-INT_MAX - 1)
  25. #define UINT_MAX (~0U)
  26. #define LONG_MAX ((long)(~0UL>>1))
  27. #define LONG_MIN (-LONG_MAX - 1)
  28. #define ULONG_MAX (~0UL)
  29. #define LLONG_MAX ((long long)(~0ULL>>1))
  30. #define LLONG_MIN (-LLONG_MAX - 1)
  31. #define ULLONG_MAX (~0ULL)
  32. #define STACK_MAGIC 0xdeadbeef
  33. #define ALIGN(x,a) __ALIGN_MASK(x,(typeof(x))(a)-1)
  34. #define __ALIGN_MASK(x,mask) (((x)+(mask))&~(mask))
  35. #define PTR_ALIGN(p, a) ((typeof(p))ALIGN((unsigned long)(p), (a)))
  36. #define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0)
  37. #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
  38. #define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
  39. #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
  40. #define roundup(x, y) ((((x) + ((y) - 1)) / (y)) * (y))
  41. #define DIV_ROUND_CLOSEST(x, divisor)( \
  42. { \
  43. typeof(divisor) __divisor = divisor; \
  44. (((x) + ((__divisor) / 2)) / (__divisor)); \
  45. } \
  46. )
  47. #define _RET_IP_ (unsigned long)__builtin_return_address(0)
  48. #define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; })
  49. #ifdef CONFIG_LBDAF
  50. # include <asm/div64.h>
  51. # define sector_div(a, b) do_div(a, b)
  52. #else
  53. # define sector_div(n, b)( \
  54. { \
  55. int _res; \
  56. _res = (n) % (b); \
  57. (n) /= (b); \
  58. _res; \
  59. } \
  60. )
  61. #endif
  62. /**
  63. * upper_32_bits - return bits 32-63 of a number
  64. * @n: the number we're accessing
  65. *
  66. * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress
  67. * the "right shift count >= width of type" warning when that quantity is
  68. * 32-bits.
  69. */
  70. #define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
  71. /**
  72. * lower_32_bits - return bits 0-31 of a number
  73. * @n: the number we're accessing
  74. */
  75. #define lower_32_bits(n) ((u32)(n))
  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. /* Use the default kernel loglevel */
  85. #define KERN_DEFAULT "<d>"
  86. /*
  87. * Annotation for a "continued" line of log printout (only done after a
  88. * line that had no enclosing \n). Only to be used by core/arch code
  89. * during early bootup (a continued line is not SMP-safe otherwise).
  90. */
  91. #define KERN_CONT "<c>"
  92. extern int console_printk[];
  93. #define console_loglevel (console_printk[0])
  94. #define default_message_loglevel (console_printk[1])
  95. #define minimum_console_loglevel (console_printk[2])
  96. #define default_console_loglevel (console_printk[3])
  97. struct completion;
  98. struct pt_regs;
  99. struct user;
  100. #ifdef CONFIG_PREEMPT_VOLUNTARY
  101. extern int _cond_resched(void);
  102. # define might_resched() _cond_resched()
  103. #else
  104. # define might_resched() do { } while (0)
  105. #endif
  106. #ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
  107. void __might_sleep(char *file, int line, int preempt_offset);
  108. /**
  109. * might_sleep - annotation for functions that can sleep
  110. *
  111. * this macro will print a stack trace if it is executed in an atomic
  112. * context (spinlock, irq-handler, ...).
  113. *
  114. * This is a useful debugging help to be able to catch problems early and not
  115. * be bitten later when the calling function happens to sleep when it is not
  116. * supposed to.
  117. */
  118. # define might_sleep() \
  119. do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
  120. #else
  121. static inline void __might_sleep(char *file, int line, int preempt_offset) { }
  122. # define might_sleep() do { might_resched(); } while (0)
  123. #endif
  124. #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
  125. #define abs(x) ({ \
  126. long __x = (x); \
  127. (__x < 0) ? -__x : __x; \
  128. })
  129. #ifdef CONFIG_PROVE_LOCKING
  130. void might_fault(void);
  131. #else
  132. static inline void might_fault(void)
  133. {
  134. might_sleep();
  135. }
  136. #endif
  137. extern struct atomic_notifier_head panic_notifier_list;
  138. extern long (*panic_blink)(long time);
  139. NORET_TYPE void panic(const char * fmt, ...)
  140. __attribute__ ((NORET_AND format (printf, 1, 2))) __cold;
  141. extern void oops_enter(void);
  142. extern void oops_exit(void);
  143. extern int oops_may_print(void);
  144. NORET_TYPE void do_exit(long error_code)
  145. ATTRIB_NORET;
  146. NORET_TYPE void complete_and_exit(struct completion *, long)
  147. ATTRIB_NORET;
  148. extern unsigned long simple_strtoul(const char *,char **,unsigned int);
  149. extern long simple_strtol(const char *,char **,unsigned int);
  150. extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
  151. extern long long simple_strtoll(const char *,char **,unsigned int);
  152. extern int strict_strtoul(const char *, unsigned int, unsigned long *);
  153. extern int strict_strtol(const char *, unsigned int, long *);
  154. extern int strict_strtoull(const char *, unsigned int, unsigned long long *);
  155. extern int strict_strtoll(const char *, unsigned int, long long *);
  156. extern int sprintf(char * buf, const char * fmt, ...)
  157. __attribute__ ((format (printf, 2, 3)));
  158. extern int vsprintf(char *buf, const char *, va_list)
  159. __attribute__ ((format (printf, 2, 0)));
  160. extern int snprintf(char * buf, size_t size, const char * fmt, ...)
  161. __attribute__ ((format (printf, 3, 4)));
  162. extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
  163. __attribute__ ((format (printf, 3, 0)));
  164. extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
  165. __attribute__ ((format (printf, 3, 4)));
  166. extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
  167. __attribute__ ((format (printf, 3, 0)));
  168. extern char *kasprintf(gfp_t gfp, const char *fmt, ...)
  169. __attribute__ ((format (printf, 2, 3)));
  170. extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args);
  171. extern int sscanf(const char *, const char *, ...)
  172. __attribute__ ((format (scanf, 2, 3)));
  173. extern int vsscanf(const char *, const char *, va_list)
  174. __attribute__ ((format (scanf, 2, 0)));
  175. extern int get_option(char **str, int *pint);
  176. extern char *get_options(const char *str, int nints, int *ints);
  177. extern unsigned long long memparse(const char *ptr, char **retptr);
  178. extern int core_kernel_text(unsigned long addr);
  179. extern int __kernel_text_address(unsigned long addr);
  180. extern int kernel_text_address(unsigned long addr);
  181. extern int func_ptr_is_kernel_text(void *ptr);
  182. struct pid;
  183. extern struct pid *session_of_pgrp(struct pid *pgrp);
  184. /*
  185. * FW_BUG
  186. * Add this to a message where you are sure the firmware is buggy or behaves
  187. * really stupid or out of spec. Be aware that the responsible BIOS developer
  188. * should be able to fix this issue or at least get a concrete idea of the
  189. * problem by reading your message without the need of looking at the kernel
  190. * code.
  191. *
  192. * Use it for definite and high priority BIOS bugs.
  193. *
  194. * FW_WARN
  195. * Use it for not that clear (e.g. could the kernel messed up things already?)
  196. * and medium priority BIOS bugs.
  197. *
  198. * FW_INFO
  199. * Use this one if you want to tell the user or vendor about something
  200. * suspicious, but generally harmless related to the firmware.
  201. *
  202. * Use it for information or very low priority BIOS bugs.
  203. */
  204. #define FW_BUG "[Firmware Bug]: "
  205. #define FW_WARN "[Firmware Warn]: "
  206. #define FW_INFO "[Firmware Info]: "
  207. #ifdef CONFIG_PRINTK
  208. asmlinkage int vprintk(const char *fmt, va_list args)
  209. __attribute__ ((format (printf, 1, 0)));
  210. asmlinkage int printk(const char * fmt, ...)
  211. __attribute__ ((format (printf, 1, 2))) __cold;
  212. extern int __printk_ratelimit(const char *func);
  213. #define printk_ratelimit() __printk_ratelimit(__func__)
  214. extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
  215. unsigned int interval_msec);
  216. extern int printk_delay_msec;
  217. /*
  218. * Print a one-time message (analogous to WARN_ONCE() et al):
  219. */
  220. #define printk_once(x...) ({ \
  221. static bool __print_once = true; \
  222. \
  223. if (__print_once) { \
  224. __print_once = false; \
  225. printk(x); \
  226. } \
  227. })
  228. void log_buf_kexec_setup(void);
  229. #else
  230. static inline int vprintk(const char *s, va_list args)
  231. __attribute__ ((format (printf, 1, 0)));
  232. static inline int vprintk(const char *s, va_list args) { return 0; }
  233. static inline int printk(const char *s, ...)
  234. __attribute__ ((format (printf, 1, 2)));
  235. static inline int __cold printk(const char *s, ...) { return 0; }
  236. static inline int printk_ratelimit(void) { return 0; }
  237. static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies, \
  238. unsigned int interval_msec) \
  239. { return false; }
  240. /* No effect, but we still get type checking even in the !PRINTK case: */
  241. #define printk_once(x...) printk(x)
  242. static inline void log_buf_kexec_setup(void)
  243. {
  244. }
  245. #endif
  246. extern int printk_needs_cpu(int cpu);
  247. extern void printk_tick(void);
  248. extern void asmlinkage __attribute__((format(printf, 1, 2)))
  249. early_printk(const char *fmt, ...);
  250. unsigned long int_sqrt(unsigned long);
  251. static inline void console_silent(void)
  252. {
  253. console_loglevel = 0;
  254. }
  255. static inline void console_verbose(void)
  256. {
  257. if (console_loglevel)
  258. console_loglevel = 15;
  259. }
  260. extern void bust_spinlocks(int yes);
  261. extern void wake_up_klogd(void);
  262. extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */
  263. extern int panic_timeout;
  264. extern int panic_on_oops;
  265. extern int panic_on_unrecovered_nmi;
  266. extern int panic_on_io_nmi;
  267. extern const char *print_tainted(void);
  268. extern void add_taint(unsigned flag);
  269. extern int test_taint(unsigned flag);
  270. extern unsigned long get_taint(void);
  271. extern int root_mountflags;
  272. /* Values used for system_state */
  273. extern enum system_states {
  274. SYSTEM_BOOTING,
  275. SYSTEM_RUNNING,
  276. SYSTEM_HALT,
  277. SYSTEM_POWER_OFF,
  278. SYSTEM_RESTART,
  279. SYSTEM_SUSPEND_DISK,
  280. } system_state;
  281. #define TAINT_PROPRIETARY_MODULE 0
  282. #define TAINT_FORCED_MODULE 1
  283. #define TAINT_UNSAFE_SMP 2
  284. #define TAINT_FORCED_RMMOD 3
  285. #define TAINT_MACHINE_CHECK 4
  286. #define TAINT_BAD_PAGE 5
  287. #define TAINT_USER 6
  288. #define TAINT_DIE 7
  289. #define TAINT_OVERRIDDEN_ACPI_TABLE 8
  290. #define TAINT_WARN 9
  291. #define TAINT_CRAP 10
  292. extern void dump_stack(void) __cold;
  293. enum {
  294. DUMP_PREFIX_NONE,
  295. DUMP_PREFIX_ADDRESS,
  296. DUMP_PREFIX_OFFSET
  297. };
  298. extern void hex_dump_to_buffer(const void *buf, size_t len,
  299. int rowsize, int groupsize,
  300. char *linebuf, size_t linebuflen, bool ascii);
  301. extern void print_hex_dump(const char *level, const char *prefix_str,
  302. int prefix_type, int rowsize, int groupsize,
  303. const void *buf, size_t len, bool ascii);
  304. extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
  305. const void *buf, size_t len);
  306. extern const char hex_asc[];
  307. #define hex_asc_lo(x) hex_asc[((x) & 0x0f)]
  308. #define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4]
  309. static inline char *pack_hex_byte(char *buf, u8 byte)
  310. {
  311. *buf++ = hex_asc_hi(byte);
  312. *buf++ = hex_asc_lo(byte);
  313. return buf;
  314. }
  315. #ifndef pr_fmt
  316. #define pr_fmt(fmt) fmt
  317. #endif
  318. #define pr_emerg(fmt, ...) \
  319. printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
  320. #define pr_alert(fmt, ...) \
  321. printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
  322. #define pr_crit(fmt, ...) \
  323. printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
  324. #define pr_err(fmt, ...) \
  325. printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
  326. #define pr_warning(fmt, ...) \
  327. printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
  328. #define pr_notice(fmt, ...) \
  329. printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
  330. #define pr_info(fmt, ...) \
  331. printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
  332. #define pr_cont(fmt, ...) \
  333. printk(KERN_CONT fmt, ##__VA_ARGS__)
  334. /* pr_devel() should produce zero code unless DEBUG is defined */
  335. #ifdef DEBUG
  336. #define pr_devel(fmt, ...) \
  337. printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
  338. #else
  339. #define pr_devel(fmt, ...) \
  340. ({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; })
  341. #endif
  342. /* If you are writing a driver, please use dev_dbg instead */
  343. #if defined(DEBUG)
  344. #define pr_debug(fmt, ...) \
  345. printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
  346. #elif defined(CONFIG_DYNAMIC_DEBUG)
  347. /* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */
  348. #define pr_debug(fmt, ...) do { \
  349. dynamic_pr_debug(fmt, ##__VA_ARGS__); \
  350. } while (0)
  351. #else
  352. #define pr_debug(fmt, ...) \
  353. ({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; })
  354. #endif
  355. /*
  356. * General tracing related utility functions - trace_printk(),
  357. * tracing_on/tracing_off and tracing_start()/tracing_stop
  358. *
  359. * Use tracing_on/tracing_off when you want to quickly turn on or off
  360. * tracing. It simply enables or disables the recording of the trace events.
  361. * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
  362. * file, which gives a means for the kernel and userspace to interact.
  363. * Place a tracing_off() in the kernel where you want tracing to end.
  364. * From user space, examine the trace, and then echo 1 > tracing_on
  365. * to continue tracing.
  366. *
  367. * tracing_stop/tracing_start has slightly more overhead. It is used
  368. * by things like suspend to ram where disabling the recording of the
  369. * trace is not enough, but tracing must actually stop because things
  370. * like calling smp_processor_id() may crash the system.
  371. *
  372. * Most likely, you want to use tracing_on/tracing_off.
  373. */
  374. #ifdef CONFIG_RING_BUFFER
  375. void tracing_on(void);
  376. void tracing_off(void);
  377. /* trace_off_permanent stops recording with no way to bring it back */
  378. void tracing_off_permanent(void);
  379. int tracing_is_on(void);
  380. #else
  381. static inline void tracing_on(void) { }
  382. static inline void tracing_off(void) { }
  383. static inline void tracing_off_permanent(void) { }
  384. static inline int tracing_is_on(void) { return 0; }
  385. #endif
  386. #ifdef CONFIG_TRACING
  387. extern void tracing_start(void);
  388. extern void tracing_stop(void);
  389. extern void ftrace_off_permanent(void);
  390. extern void
  391. ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3);
  392. static inline void __attribute__ ((format (printf, 1, 2)))
  393. ____trace_printk_check_format(const char *fmt, ...)
  394. {
  395. }
  396. #define __trace_printk_check_format(fmt, args...) \
  397. do { \
  398. if (0) \
  399. ____trace_printk_check_format(fmt, ##args); \
  400. } while (0)
  401. /**
  402. * trace_printk - printf formatting in the ftrace buffer
  403. * @fmt: the printf format for printing
  404. *
  405. * Note: __trace_printk is an internal function for trace_printk and
  406. * the @ip is passed in via the trace_printk macro.
  407. *
  408. * This function allows a kernel developer to debug fast path sections
  409. * that printk is not appropriate for. By scattering in various
  410. * printk like tracing in the code, a developer can quickly see
  411. * where problems are occurring.
  412. *
  413. * This is intended as a debugging tool for the developer only.
  414. * Please refrain from leaving trace_printks scattered around in
  415. * your code.
  416. */
  417. #define trace_printk(fmt, args...) \
  418. do { \
  419. __trace_printk_check_format(fmt, ##args); \
  420. if (__builtin_constant_p(fmt)) { \
  421. static const char *trace_printk_fmt \
  422. __attribute__((section("__trace_printk_fmt"))) = \
  423. __builtin_constant_p(fmt) ? fmt : NULL; \
  424. \
  425. __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \
  426. } else \
  427. __trace_printk(_THIS_IP_, fmt, ##args); \
  428. } while (0)
  429. extern int
  430. __trace_bprintk(unsigned long ip, const char *fmt, ...)
  431. __attribute__ ((format (printf, 2, 3)));
  432. extern int
  433. __trace_printk(unsigned long ip, const char *fmt, ...)
  434. __attribute__ ((format (printf, 2, 3)));
  435. extern void trace_dump_stack(void);
  436. /*
  437. * The double __builtin_constant_p is because gcc will give us an error
  438. * if we try to allocate the static variable to fmt if it is not a
  439. * constant. Even with the outer if statement.
  440. */
  441. #define ftrace_vprintk(fmt, vargs) \
  442. do { \
  443. if (__builtin_constant_p(fmt)) { \
  444. static const char *trace_printk_fmt \
  445. __attribute__((section("__trace_printk_fmt"))) = \
  446. __builtin_constant_p(fmt) ? fmt : NULL; \
  447. \
  448. __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \
  449. } else \
  450. __ftrace_vprintk(_THIS_IP_, fmt, vargs); \
  451. } while (0)
  452. extern int
  453. __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap);
  454. extern int
  455. __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap);
  456. extern void ftrace_dump(void);
  457. #else
  458. static inline void
  459. ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) { }
  460. static inline int
  461. trace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 2)));
  462. static inline void tracing_start(void) { }
  463. static inline void tracing_stop(void) { }
  464. static inline void ftrace_off_permanent(void) { }
  465. static inline int
  466. trace_printk(const char *fmt, ...)
  467. {
  468. return 0;
  469. }
  470. static inline int
  471. ftrace_vprintk(const char *fmt, va_list ap)
  472. {
  473. return 0;
  474. }
  475. static inline void ftrace_dump(void) { }
  476. #endif /* CONFIG_TRACING */
  477. /*
  478. * Display an IP address in readable format.
  479. */
  480. #define NIPQUAD(addr) \
  481. ((unsigned char *)&addr)[0], \
  482. ((unsigned char *)&addr)[1], \
  483. ((unsigned char *)&addr)[2], \
  484. ((unsigned char *)&addr)[3]
  485. #define NIPQUAD_FMT "%u.%u.%u.%u"
  486. /*
  487. * min()/max()/clamp() macros that also do
  488. * strict type-checking.. See the
  489. * "unnecessary" pointer comparison.
  490. */
  491. #define min(x, y) ({ \
  492. typeof(x) _min1 = (x); \
  493. typeof(y) _min2 = (y); \
  494. (void) (&_min1 == &_min2); \
  495. _min1 < _min2 ? _min1 : _min2; })
  496. #define max(x, y) ({ \
  497. typeof(x) _max1 = (x); \
  498. typeof(y) _max2 = (y); \
  499. (void) (&_max1 == &_max2); \
  500. _max1 > _max2 ? _max1 : _max2; })
  501. /**
  502. * clamp - return a value clamped to a given range with strict typechecking
  503. * @val: current value
  504. * @min: minimum allowable value
  505. * @max: maximum allowable value
  506. *
  507. * This macro does strict typechecking of min/max to make sure they are of the
  508. * same type as val. See the unnecessary pointer comparisons.
  509. */
  510. #define clamp(val, min, max) ({ \
  511. typeof(val) __val = (val); \
  512. typeof(min) __min = (min); \
  513. typeof(max) __max = (max); \
  514. (void) (&__val == &__min); \
  515. (void) (&__val == &__max); \
  516. __val = __val < __min ? __min: __val; \
  517. __val > __max ? __max: __val; })
  518. /*
  519. * ..and if you can't take the strict
  520. * types, you can specify one yourself.
  521. *
  522. * Or not use min/max/clamp at all, of course.
  523. */
  524. #define min_t(type, x, y) ({ \
  525. type __min1 = (x); \
  526. type __min2 = (y); \
  527. __min1 < __min2 ? __min1: __min2; })
  528. #define max_t(type, x, y) ({ \
  529. type __max1 = (x); \
  530. type __max2 = (y); \
  531. __max1 > __max2 ? __max1: __max2; })
  532. /**
  533. * clamp_t - return a value clamped to a given range using a given type
  534. * @type: the type of variable to use
  535. * @val: current value
  536. * @min: minimum allowable value
  537. * @max: maximum allowable value
  538. *
  539. * This macro does no typechecking and uses temporary variables of type
  540. * 'type' to make all the comparisons.
  541. */
  542. #define clamp_t(type, val, min, max) ({ \
  543. type __val = (val); \
  544. type __min = (min); \
  545. type __max = (max); \
  546. __val = __val < __min ? __min: __val; \
  547. __val > __max ? __max: __val; })
  548. /**
  549. * clamp_val - return a value clamped to a given range using val's type
  550. * @val: current value
  551. * @min: minimum allowable value
  552. * @max: maximum allowable value
  553. *
  554. * This macro does no typechecking and uses temporary variables of whatever
  555. * type the input argument 'val' is. This is useful when val is an unsigned
  556. * type and min and max are literals that will otherwise be assigned a signed
  557. * integer type.
  558. */
  559. #define clamp_val(val, min, max) ({ \
  560. typeof(val) __val = (val); \
  561. typeof(val) __min = (min); \
  562. typeof(val) __max = (max); \
  563. __val = __val < __min ? __min: __val; \
  564. __val > __max ? __max: __val; })
  565. /*
  566. * swap - swap value of @a and @b
  567. */
  568. #define swap(a, b) \
  569. do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
  570. /**
  571. * container_of - cast a member of a structure out to the containing structure
  572. * @ptr: the pointer to the member.
  573. * @type: the type of the container struct this is embedded in.
  574. * @member: the name of the member within the struct.
  575. *
  576. */
  577. #define container_of(ptr, type, member) ({ \
  578. const typeof( ((type *)0)->member ) *__mptr = (ptr); \
  579. (type *)( (char *)__mptr - offsetof(type,member) );})
  580. struct sysinfo;
  581. extern int do_sysinfo(struct sysinfo *info);
  582. #endif /* __KERNEL__ */
  583. #ifndef __EXPORTED_HEADERS__
  584. #ifndef __KERNEL__
  585. #warning Attempt to use kernel headers from user space, see http://kernelnewbies.org/KernelHeaders
  586. #endif /* __KERNEL__ */
  587. #endif /* __EXPORTED_HEADERS__ */
  588. #define SI_LOAD_SHIFT 16
  589. struct sysinfo {
  590. long uptime; /* Seconds since boot */
  591. unsigned long loads[3]; /* 1, 5, and 15 minute load averages */
  592. unsigned long totalram; /* Total usable main memory size */
  593. unsigned long freeram; /* Available memory size */
  594. unsigned long sharedram; /* Amount of shared memory */
  595. unsigned long bufferram; /* Memory used by buffers */
  596. unsigned long totalswap; /* Total swap space size */
  597. unsigned long freeswap; /* swap space still available */
  598. unsigned short procs; /* Number of current processes */
  599. unsigned short pad; /* explicit padding for m68k */
  600. unsigned long totalhigh; /* Total high memory size */
  601. unsigned long freehigh; /* Available high memory size */
  602. unsigned int mem_unit; /* Memory unit size in bytes */
  603. char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */
  604. };
  605. /* Force a compilation error if condition is true */
  606. #define BUILD_BUG_ON(condition) ((void)BUILD_BUG_ON_ZERO(condition))
  607. /* Force a compilation error if condition is constant and true */
  608. #define MAYBE_BUILD_BUG_ON(cond) ((void)sizeof(char[1 - 2 * !!(cond)]))
  609. /* Force a compilation error if condition is true, but also produce a
  610. result (of value 0 and type size_t), so the expression can be used
  611. e.g. in a structure initializer (or where-ever else comma expressions
  612. aren't permitted). */
  613. #define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
  614. #define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))
  615. /* Trap pasters of __FUNCTION__ at compile-time */
  616. #define __FUNCTION__ (__func__)
  617. /* This helps us to avoid #ifdef CONFIG_NUMA */
  618. #ifdef CONFIG_NUMA
  619. #define NUMA_BUILD 1
  620. #else
  621. #define NUMA_BUILD 0
  622. #endif
  623. /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
  624. #ifdef CONFIG_FTRACE_MCOUNT_RECORD
  625. # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
  626. #endif
  627. #endif