1 #ifndef _LINUX_KERNEL_H
2 #define _LINUX_KERNEL_H
6 #include <linux/linkage.h>
7 #include <linux/stddef.h>
8 #include <linux/types.h>
9 #include <linux/compiler.h>
10 #include <linux/bitops.h>
11 #include <linux/log2.h>
12 #include <linux/typecheck.h>
13 #include <linux/printk.h>
14 #include <linux/build_bug.h>
15 #include <asm/byteorder.h>
16 #include <uapi/linux/kernel.h>
18 #define USHRT_MAX ((u16)(~0U))
19 #define SHRT_MAX ((s16)(USHRT_MAX>>1))
20 #define SHRT_MIN ((s16)(-SHRT_MAX - 1))
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 #define LLONG_MAX ((long long)(~0ULL>>1))
28 #define LLONG_MIN (-LLONG_MAX - 1)
29 #define ULLONG_MAX (~0ULL)
30 #define SIZE_MAX (~(size_t)0)
32 #define U8_MAX ((u8)~0U)
33 #define S8_MAX ((s8)(U8_MAX>>1))
34 #define S8_MIN ((s8)(-S8_MAX - 1))
35 #define U16_MAX ((u16)~0U)
36 #define S16_MAX ((s16)(U16_MAX>>1))
37 #define S16_MIN ((s16)(-S16_MAX - 1))
38 #define U32_MAX ((u32)~0U)
39 #define S32_MAX ((s32)(U32_MAX>>1))
40 #define S32_MIN ((s32)(-S32_MAX - 1))
41 #define U64_MAX ((u64)~0ULL)
42 #define S64_MAX ((s64)(U64_MAX>>1))
43 #define S64_MIN ((s64)(-S64_MAX - 1))
45 #define STACK_MAGIC 0xdeadbeef
48 * REPEAT_BYTE - repeat the value @x multiple times as an unsigned long value
51 * NOTE: @x is not checked for > 0xff; larger values produce odd results.
53 #define REPEAT_BYTE(x) ((~0ul / 0xff) * (x))
55 /* @a is a power of 2 value */
56 #define ALIGN(x, a) __ALIGN_KERNEL((x), (a))
57 #define ALIGN_DOWN(x, a) __ALIGN_KERNEL((x) - ((a) - 1), (a))
58 #define __ALIGN_MASK(x, mask) __ALIGN_KERNEL_MASK((x), (mask))
59 #define PTR_ALIGN(p, a) ((typeof(p))ALIGN((unsigned long)(p), (a)))
60 #define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0)
62 /* generic data direction definitions */
67 * ARRAY_SIZE - get the number of elements in array @arr
68 * @arr: array to be sized
70 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
72 #define u64_to_user_ptr(x) ( \
75 (void __user *)(uintptr_t)x; \
80 * This looks more complex than it should be. But we need to
81 * get the type for the ~ right in round_down (it needs to be
82 * as wide as the result!), and we want to evaluate the macro
83 * arguments just once each.
85 #define __round_mask(x, y) ((__typeof__(x))((y)-1))
86 #define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1)
87 #define round_down(x, y) ((x) & ~__round_mask(x, y))
90 * FIELD_SIZEOF - get the size of a struct's field
91 * @t: the target struct
92 * @f: the target struct's field
93 * Return: the size of @f in the struct definition without having a
94 * declared instance of @t.
96 #define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
98 #define DIV_ROUND_UP __KERNEL_DIV_ROUND_UP
100 #define DIV_ROUND_DOWN_ULL(ll, d) \
101 ({ unsigned long long _tmp = (ll); do_div(_tmp, d); _tmp; })
103 #define DIV_ROUND_UP_ULL(ll, d) DIV_ROUND_DOWN_ULL((ll) + (d) - 1, (d))
105 #if BITS_PER_LONG == 32
106 # define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP_ULL(ll, d)
108 # define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP(ll,d)
111 /* The `const' in roundup() prevents gcc-3.3 from calling __divdi3 */
112 #define roundup(x, y) ( \
114 const typeof(y) __y = y; \
115 (((x) + (__y - 1)) / __y) * __y; \
118 #define rounddown(x, y) ( \
120 typeof(x) __x = (x); \
126 * Divide positive or negative dividend by positive or negative divisor
127 * and round to closest integer. Result is undefined for negative
128 * divisors if the dividend variable type is unsigned and for negative
129 * dividends if the divisor variable type is unsigned.
131 #define DIV_ROUND_CLOSEST(x, divisor)( \
134 typeof(divisor) __d = divisor; \
135 (((typeof(x))-1) > 0 || \
136 ((typeof(divisor))-1) > 0 || \
137 (((__x) > 0) == ((__d) > 0))) ? \
138 (((__x) + ((__d) / 2)) / (__d)) : \
139 (((__x) - ((__d) / 2)) / (__d)); \
143 * Same as above but for u64 dividends. divisor must be a 32-bit
146 #define DIV_ROUND_CLOSEST_ULL(x, divisor)( \
148 typeof(divisor) __d = divisor; \
149 unsigned long long _tmp = (x) + (__d) / 2; \
156 * Multiplies an integer by a fraction, while avoiding unnecessary
157 * overflow or loss of precision.
159 #define mult_frac(x, numer, denom)( \
161 typeof(x) quot = (x) / (denom); \
162 typeof(x) rem = (x) % (denom); \
163 (quot * (numer)) + ((rem * (numer)) / (denom)); \
168 #define _RET_IP_ (unsigned long)__builtin_return_address(0)
169 #define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; })
172 # include <asm/div64.h>
173 # define sector_div(a, b) do_div(a, b)
175 # define sector_div(n, b)( \
186 * upper_32_bits - return bits 32-63 of a number
187 * @n: the number we're accessing
189 * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress
190 * the "right shift count >= width of type" warning when that quantity is
193 #define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
196 * lower_32_bits - return bits 0-31 of a number
197 * @n: the number we're accessing
199 #define lower_32_bits(n) ((u32)(n))
205 #ifdef CONFIG_PREEMPT_VOLUNTARY
206 extern int _cond_resched(void);
207 # define might_resched() _cond_resched()
209 # define might_resched() do { } while (0)
212 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
213 void ___might_sleep(const char *file, int line, int preempt_offset);
214 void __might_sleep(const char *file, int line, int preempt_offset);
216 * might_sleep - annotation for functions that can sleep
218 * this macro will print a stack trace if it is executed in an atomic
219 * context (spinlock, irq-handler, ...).
221 * This is a useful debugging help to be able to catch problems early and not
222 * be bitten later when the calling function happens to sleep when it is not
225 # define might_sleep() \
226 do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
227 # define sched_annotate_sleep() (current->task_state_change = 0)
229 static inline void ___might_sleep(const char *file, int line,
230 int preempt_offset) { }
231 static inline void __might_sleep(const char *file, int line,
232 int preempt_offset) { }
233 # define might_sleep() do { might_resched(); } while (0)
234 # define sched_annotate_sleep() do { } while (0)
237 #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
240 * abs - return absolute value of an argument
241 * @x: the value. If it is unsigned type, it is converted to signed type first.
242 * char is treated as if it was signed (regardless of whether it really is)
243 * but the macro's return type is preserved as char.
245 * Return: an absolute value of x.
247 #define abs(x) __abs_choose_expr(x, long long, \
248 __abs_choose_expr(x, long, \
249 __abs_choose_expr(x, int, \
250 __abs_choose_expr(x, short, \
251 __abs_choose_expr(x, char, \
252 __builtin_choose_expr( \
253 __builtin_types_compatible_p(typeof(x), char), \
254 (char)({ signed char __x = (x); __x<0?-__x:__x; }), \
257 #define __abs_choose_expr(x, type, other) __builtin_choose_expr( \
258 __builtin_types_compatible_p(typeof(x), signed type) || \
259 __builtin_types_compatible_p(typeof(x), unsigned type), \
260 ({ signed type __x = (x); __x < 0 ? -__x : __x; }), other)
263 * reciprocal_scale - "scale" a value into range [0, ep_ro)
265 * @ep_ro: right open interval endpoint
267 * Perform a "reciprocal multiplication" in order to "scale" a value into
268 * range [0, @ep_ro), where the upper interval endpoint is right-open.
269 * This is useful, e.g. for accessing a index of an array containing
270 * @ep_ro elements, for example. Think of it as sort of modulus, only that
271 * the result isn't that of modulo. ;) Note that if initial input is a
272 * small value, then result will return 0.
274 * Return: a result based on @val in interval [0, @ep_ro).
276 static inline u32 reciprocal_scale(u32 val, u32 ep_ro)
278 return (u32)(((u64) val * ep_ro) >> 32);
281 #if defined(CONFIG_MMU) && \
282 (defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_DEBUG_ATOMIC_SLEEP))
283 #define might_fault() __might_fault(__FILE__, __LINE__)
284 void __might_fault(const char *file, int line);
286 static inline void might_fault(void) { }
289 extern struct atomic_notifier_head panic_notifier_list;
290 extern long (*panic_blink)(int state);
292 void panic(const char *fmt, ...) __noreturn __cold;
293 void nmi_panic(struct pt_regs *regs, const char *msg);
294 extern void oops_enter(void);
295 extern void oops_exit(void);
296 void print_oops_end_marker(void);
297 extern int oops_may_print(void);
298 void do_exit(long error_code) __noreturn;
299 void complete_and_exit(struct completion *, long) __noreturn;
301 #ifdef CONFIG_ARCH_HAS_REFCOUNT
302 void refcount_error_report(struct pt_regs *regs, const char *err);
304 static inline void refcount_error_report(struct pt_regs *regs, const char *err)
308 /* Internal, do not use. */
309 int __must_check _kstrtoul(const char *s, unsigned int base, unsigned long *res);
310 int __must_check _kstrtol(const char *s, unsigned int base, long *res);
312 int __must_check kstrtoull(const char *s, unsigned int base, unsigned long long *res);
313 int __must_check kstrtoll(const char *s, unsigned int base, long long *res);
316 * kstrtoul - convert a string to an unsigned long
317 * @s: The start of the string. The string must be null-terminated, and may also
318 * include a single newline before its terminating null. The first character
319 * may also be a plus sign, but not a minus sign.
320 * @base: The number base to use. The maximum supported base is 16. If base is
321 * given as 0, then the base of the string is automatically detected with the
322 * conventional semantics - If it begins with 0x the number will be parsed as a
323 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be
324 * parsed as an octal number. Otherwise it will be parsed as a decimal.
325 * @res: Where to write the result of the conversion on success.
327 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
328 * Used as a replacement for the obsolete simple_strtoull. Return code must
331 static inline int __must_check kstrtoul(const char *s, unsigned int base, unsigned long *res)
334 * We want to shortcut function call, but
335 * __builtin_types_compatible_p(unsigned long, unsigned long long) = 0.
337 if (sizeof(unsigned long) == sizeof(unsigned long long) &&
338 __alignof__(unsigned long) == __alignof__(unsigned long long))
339 return kstrtoull(s, base, (unsigned long long *)res);
341 return _kstrtoul(s, base, res);
345 * kstrtol - convert a string to a long
346 * @s: The start of the string. The string must be null-terminated, and may also
347 * include a single newline before its terminating null. The first character
348 * may also be a plus sign or a minus sign.
349 * @base: The number base to use. The maximum supported base is 16. If base is
350 * given as 0, then the base of the string is automatically detected with the
351 * conventional semantics - If it begins with 0x the number will be parsed as a
352 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be
353 * parsed as an octal number. Otherwise it will be parsed as a decimal.
354 * @res: Where to write the result of the conversion on success.
356 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
357 * Used as a replacement for the obsolete simple_strtoull. Return code must
360 static inline int __must_check kstrtol(const char *s, unsigned int base, long *res)
363 * We want to shortcut function call, but
364 * __builtin_types_compatible_p(long, long long) = 0.
366 if (sizeof(long) == sizeof(long long) &&
367 __alignof__(long) == __alignof__(long long))
368 return kstrtoll(s, base, (long long *)res);
370 return _kstrtol(s, base, res);
373 int __must_check kstrtouint(const char *s, unsigned int base, unsigned int *res);
374 int __must_check kstrtoint(const char *s, unsigned int base, int *res);
376 static inline int __must_check kstrtou64(const char *s, unsigned int base, u64 *res)
378 return kstrtoull(s, base, res);
381 static inline int __must_check kstrtos64(const char *s, unsigned int base, s64 *res)
383 return kstrtoll(s, base, res);
386 static inline int __must_check kstrtou32(const char *s, unsigned int base, u32 *res)
388 return kstrtouint(s, base, res);
391 static inline int __must_check kstrtos32(const char *s, unsigned int base, s32 *res)
393 return kstrtoint(s, base, res);
396 int __must_check kstrtou16(const char *s, unsigned int base, u16 *res);
397 int __must_check kstrtos16(const char *s, unsigned int base, s16 *res);
398 int __must_check kstrtou8(const char *s, unsigned int base, u8 *res);
399 int __must_check kstrtos8(const char *s, unsigned int base, s8 *res);
400 int __must_check kstrtobool(const char *s, bool *res);
402 int __must_check kstrtoull_from_user(const char __user *s, size_t count, unsigned int base, unsigned long long *res);
403 int __must_check kstrtoll_from_user(const char __user *s, size_t count, unsigned int base, long long *res);
404 int __must_check kstrtoul_from_user(const char __user *s, size_t count, unsigned int base, unsigned long *res);
405 int __must_check kstrtol_from_user(const char __user *s, size_t count, unsigned int base, long *res);
406 int __must_check kstrtouint_from_user(const char __user *s, size_t count, unsigned int base, unsigned int *res);
407 int __must_check kstrtoint_from_user(const char __user *s, size_t count, unsigned int base, int *res);
408 int __must_check kstrtou16_from_user(const char __user *s, size_t count, unsigned int base, u16 *res);
409 int __must_check kstrtos16_from_user(const char __user *s, size_t count, unsigned int base, s16 *res);
410 int __must_check kstrtou8_from_user(const char __user *s, size_t count, unsigned int base, u8 *res);
411 int __must_check kstrtos8_from_user(const char __user *s, size_t count, unsigned int base, s8 *res);
412 int __must_check kstrtobool_from_user(const char __user *s, size_t count, bool *res);
414 static inline int __must_check kstrtou64_from_user(const char __user *s, size_t count, unsigned int base, u64 *res)
416 return kstrtoull_from_user(s, count, base, res);
419 static inline int __must_check kstrtos64_from_user(const char __user *s, size_t count, unsigned int base, s64 *res)
421 return kstrtoll_from_user(s, count, base, res);
424 static inline int __must_check kstrtou32_from_user(const char __user *s, size_t count, unsigned int base, u32 *res)
426 return kstrtouint_from_user(s, count, base, res);
429 static inline int __must_check kstrtos32_from_user(const char __user *s, size_t count, unsigned int base, s32 *res)
431 return kstrtoint_from_user(s, count, base, res);
434 /* Obsolete, do not use. Use kstrto<foo> instead */
436 extern unsigned long simple_strtoul(const char *,char **,unsigned int);
437 extern long simple_strtol(const char *,char **,unsigned int);
438 extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
439 extern long long simple_strtoll(const char *,char **,unsigned int);
441 extern int num_to_str(char *buf, int size, unsigned long long num);
443 /* lib/printf utilities */
445 extern __printf(2, 3) int sprintf(char *buf, const char * fmt, ...);
446 extern __printf(2, 0) int vsprintf(char *buf, const char *, va_list);
447 extern __printf(3, 4)
448 int snprintf(char *buf, size_t size, const char *fmt, ...);
449 extern __printf(3, 0)
450 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args);
451 extern __printf(3, 4)
452 int scnprintf(char *buf, size_t size, const char *fmt, ...);
453 extern __printf(3, 0)
454 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args);
455 extern __printf(2, 3) __malloc
456 char *kasprintf(gfp_t gfp, const char *fmt, ...);
457 extern __printf(2, 0) __malloc
458 char *kvasprintf(gfp_t gfp, const char *fmt, va_list args);
459 extern __printf(2, 0)
460 const char *kvasprintf_const(gfp_t gfp, const char *fmt, va_list args);
463 int sscanf(const char *, const char *, ...);
465 int vsscanf(const char *, const char *, va_list);
467 extern int get_option(char **str, int *pint);
468 extern char *get_options(const char *str, int nints, int *ints);
469 extern unsigned long long memparse(const char *ptr, char **retptr);
470 extern bool parse_option_str(const char *str, const char *option);
471 extern char *next_arg(char *args, char **param, char **val);
473 extern int core_kernel_text(unsigned long addr);
474 extern int core_kernel_data(unsigned long addr);
475 extern int __kernel_text_address(unsigned long addr);
476 extern int kernel_text_address(unsigned long addr);
477 extern int func_ptr_is_kernel_text(void *ptr);
479 unsigned long int_sqrt(unsigned long);
481 extern void bust_spinlocks(int yes);
482 extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */
483 extern int panic_timeout;
484 extern int panic_on_oops;
485 extern int panic_on_unrecovered_nmi;
486 extern int panic_on_io_nmi;
487 extern int panic_on_warn;
488 extern int sysctl_panic_on_rcu_stall;
489 extern int sysctl_panic_on_stackoverflow;
491 extern bool crash_kexec_post_notifiers;
494 * panic_cpu is used for synchronizing panic() and crash_kexec() execution. It
495 * holds a CPU number which is executing panic() currently. A value of
496 * PANIC_CPU_INVALID means no CPU has entered panic() or crash_kexec().
498 extern atomic_t panic_cpu;
499 #define PANIC_CPU_INVALID -1
502 * Only to be used by arch init code. If the user over-wrote the default
503 * CONFIG_PANIC_TIMEOUT, honor it.
505 static inline void set_arch_panic_timeout(int timeout, int arch_default_timeout)
507 if (panic_timeout == arch_default_timeout)
508 panic_timeout = timeout;
510 extern const char *print_tainted(void);
513 LOCKDEP_NOW_UNRELIABLE
515 extern void add_taint(unsigned flag, enum lockdep_ok);
516 extern int test_taint(unsigned flag);
517 extern unsigned long get_taint(void);
518 extern int root_mountflags;
520 extern bool early_boot_irqs_disabled;
523 * Values used for system_state. Ordering of the states must not be changed
524 * as code checks for <, <=, >, >= STATE.
526 extern enum system_states {
535 #define TAINT_PROPRIETARY_MODULE 0
536 #define TAINT_FORCED_MODULE 1
537 #define TAINT_CPU_OUT_OF_SPEC 2
538 #define TAINT_FORCED_RMMOD 3
539 #define TAINT_MACHINE_CHECK 4
540 #define TAINT_BAD_PAGE 5
543 #define TAINT_OVERRIDDEN_ACPI_TABLE 8
545 #define TAINT_CRAP 10
546 #define TAINT_FIRMWARE_WORKAROUND 11
547 #define TAINT_OOT_MODULE 12
548 #define TAINT_UNSIGNED_MODULE 13
549 #define TAINT_SOFTLOCKUP 14
550 #define TAINT_LIVEPATCH 15
551 #define TAINT_FLAGS_COUNT 16
554 char c_true; /* character printed when tainted */
555 char c_false; /* character printed when not tainted */
556 bool module; /* also show as a per-module taint flag */
559 extern const struct taint_flag taint_flags[TAINT_FLAGS_COUNT];
561 extern const char hex_asc[];
562 #define hex_asc_lo(x) hex_asc[((x) & 0x0f)]
563 #define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4]
565 static inline char *hex_byte_pack(char *buf, u8 byte)
567 *buf++ = hex_asc_hi(byte);
568 *buf++ = hex_asc_lo(byte);
572 extern const char hex_asc_upper[];
573 #define hex_asc_upper_lo(x) hex_asc_upper[((x) & 0x0f)]
574 #define hex_asc_upper_hi(x) hex_asc_upper[((x) & 0xf0) >> 4]
576 static inline char *hex_byte_pack_upper(char *buf, u8 byte)
578 *buf++ = hex_asc_upper_hi(byte);
579 *buf++ = hex_asc_upper_lo(byte);
583 extern int hex_to_bin(char ch);
584 extern int __must_check hex2bin(u8 *dst, const char *src, size_t count);
585 extern char *bin2hex(char *dst, const void *src, size_t count);
587 bool mac_pton(const char *s, u8 *mac);
590 * General tracing related utility functions - trace_printk(),
591 * tracing_on/tracing_off and tracing_start()/tracing_stop
593 * Use tracing_on/tracing_off when you want to quickly turn on or off
594 * tracing. It simply enables or disables the recording of the trace events.
595 * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
596 * file, which gives a means for the kernel and userspace to interact.
597 * Place a tracing_off() in the kernel where you want tracing to end.
598 * From user space, examine the trace, and then echo 1 > tracing_on
599 * to continue tracing.
601 * tracing_stop/tracing_start has slightly more overhead. It is used
602 * by things like suspend to ram where disabling the recording of the
603 * trace is not enough, but tracing must actually stop because things
604 * like calling smp_processor_id() may crash the system.
606 * Most likely, you want to use tracing_on/tracing_off.
609 enum ftrace_dump_mode {
615 #ifdef CONFIG_TRACING
616 void tracing_on(void);
617 void tracing_off(void);
618 int tracing_is_on(void);
619 void tracing_snapshot(void);
620 void tracing_snapshot_alloc(void);
622 extern void tracing_start(void);
623 extern void tracing_stop(void);
625 static inline __printf(1, 2)
626 void ____trace_printk_check_format(const char *fmt, ...)
629 #define __trace_printk_check_format(fmt, args...) \
632 ____trace_printk_check_format(fmt, ##args); \
636 * trace_printk - printf formatting in the ftrace buffer
637 * @fmt: the printf format for printing
639 * Note: __trace_printk is an internal function for trace_printk() and
640 * the @ip is passed in via the trace_printk() macro.
642 * This function allows a kernel developer to debug fast path sections
643 * that printk is not appropriate for. By scattering in various
644 * printk like tracing in the code, a developer can quickly see
645 * where problems are occurring.
647 * This is intended as a debugging tool for the developer only.
648 * Please refrain from leaving trace_printks scattered around in
649 * your code. (Extra memory is used for special buffers that are
650 * allocated when trace_printk() is used.)
652 * A little optization trick is done here. If there's only one
653 * argument, there's no need to scan the string for printf formats.
654 * The trace_puts() will suffice. But how can we take advantage of
655 * using trace_puts() when trace_printk() has only one argument?
656 * By stringifying the args and checking the size we can tell
657 * whether or not there are args. __stringify((__VA_ARGS__)) will
658 * turn into "()\0" with a size of 3 when there are no args, anything
659 * else will be bigger. All we need to do is define a string to this,
660 * and then take its size and compare to 3. If it's bigger, use
661 * do_trace_printk() otherwise, optimize it to trace_puts(). Then just
662 * let gcc optimize the rest.
665 #define trace_printk(fmt, ...) \
667 char _______STR[] = __stringify((__VA_ARGS__)); \
668 if (sizeof(_______STR) > 3) \
669 do_trace_printk(fmt, ##__VA_ARGS__); \
674 #define do_trace_printk(fmt, args...) \
676 static const char *trace_printk_fmt __used \
677 __attribute__((section("__trace_printk_fmt"))) = \
678 __builtin_constant_p(fmt) ? fmt : NULL; \
680 __trace_printk_check_format(fmt, ##args); \
682 if (__builtin_constant_p(fmt)) \
683 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \
685 __trace_printk(_THIS_IP_, fmt, ##args); \
688 extern __printf(2, 3)
689 int __trace_bprintk(unsigned long ip, const char *fmt, ...);
691 extern __printf(2, 3)
692 int __trace_printk(unsigned long ip, const char *fmt, ...);
695 * trace_puts - write a string into the ftrace buffer
696 * @str: the string to record
698 * Note: __trace_bputs is an internal function for trace_puts and
699 * the @ip is passed in via the trace_puts macro.
701 * This is similar to trace_printk() but is made for those really fast
702 * paths that a developer wants the least amount of "Heisenbug" effects,
703 * where the processing of the print format is still too much.
705 * This function allows a kernel developer to debug fast path sections
706 * that printk is not appropriate for. By scattering in various
707 * printk like tracing in the code, a developer can quickly see
708 * where problems are occurring.
710 * This is intended as a debugging tool for the developer only.
711 * Please refrain from leaving trace_puts scattered around in
712 * your code. (Extra memory is used for special buffers that are
713 * allocated when trace_puts() is used.)
715 * Returns: 0 if nothing was written, positive # if string was.
716 * (1 when __trace_bputs is used, strlen(str) when __trace_puts is used)
719 #define trace_puts(str) ({ \
720 static const char *trace_printk_fmt __used \
721 __attribute__((section("__trace_printk_fmt"))) = \
722 __builtin_constant_p(str) ? str : NULL; \
724 if (__builtin_constant_p(str)) \
725 __trace_bputs(_THIS_IP_, trace_printk_fmt); \
727 __trace_puts(_THIS_IP_, str, strlen(str)); \
729 extern int __trace_bputs(unsigned long ip, const char *str);
730 extern int __trace_puts(unsigned long ip, const char *str, int size);
732 extern void trace_dump_stack(int skip);
735 * The double __builtin_constant_p is because gcc will give us an error
736 * if we try to allocate the static variable to fmt if it is not a
737 * constant. Even with the outer if statement.
739 #define ftrace_vprintk(fmt, vargs) \
741 if (__builtin_constant_p(fmt)) { \
742 static const char *trace_printk_fmt __used \
743 __attribute__((section("__trace_printk_fmt"))) = \
744 __builtin_constant_p(fmt) ? fmt : NULL; \
746 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \
748 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \
751 extern __printf(2, 0) int
752 __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap);
754 extern __printf(2, 0) int
755 __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap);
757 extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode);
759 static inline void tracing_start(void) { }
760 static inline void tracing_stop(void) { }
761 static inline void trace_dump_stack(int skip) { }
763 static inline void tracing_on(void) { }
764 static inline void tracing_off(void) { }
765 static inline int tracing_is_on(void) { return 0; }
766 static inline void tracing_snapshot(void) { }
767 static inline void tracing_snapshot_alloc(void) { }
769 static inline __printf(1, 2)
770 int trace_printk(const char *fmt, ...)
774 static __printf(1, 0) inline int
775 ftrace_vprintk(const char *fmt, va_list ap)
779 static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
780 #endif /* CONFIG_TRACING */
783 * min()/max()/clamp() macros that also do
784 * strict type-checking.. See the
785 * "unnecessary" pointer comparison.
787 #define __min(t1, t2, min1, min2, x, y) ({ \
790 (void) (&min1 == &min2); \
791 min1 < min2 ? min1 : min2; })
794 * min - return minimum of two values of the same or compatible types
799 __min(typeof(x), typeof(y), \
800 __UNIQUE_ID(min1_), __UNIQUE_ID(min2_), \
803 #define __max(t1, t2, max1, max2, x, y) ({ \
806 (void) (&max1 == &max2); \
807 max1 > max2 ? max1 : max2; })
810 * max - return maximum of two values of the same or compatible types
815 __max(typeof(x), typeof(y), \
816 __UNIQUE_ID(max1_), __UNIQUE_ID(max2_), \
820 * min3 - return minimum of three values
825 #define min3(x, y, z) min((typeof(x))min(x, y), z)
828 * max3 - return maximum of three values
833 #define max3(x, y, z) max((typeof(x))max(x, y), z)
836 * min_not_zero - return the minimum that is _not_ zero, unless both are zero
840 #define min_not_zero(x, y) ({ \
841 typeof(x) __x = (x); \
842 typeof(y) __y = (y); \
843 __x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); })
846 * clamp - return a value clamped to a given range with strict typechecking
847 * @val: current value
848 * @lo: lowest allowable value
849 * @hi: highest allowable value
851 * This macro does strict typechecking of @lo/@hi to make sure they are of the
852 * same type as @val. See the unnecessary pointer comparisons.
854 #define clamp(val, lo, hi) min((typeof(val))max(val, lo), hi)
857 * ..and if you can't take the strict
858 * types, you can specify one yourself.
860 * Or not use min/max/clamp at all, of course.
864 * min_t - return minimum of two values, using the specified type
865 * @type: data type to use
869 #define min_t(type, x, y) \
871 __UNIQUE_ID(min1_), __UNIQUE_ID(min2_), \
875 * max_t - return maximum of two values, using the specified type
876 * @type: data type to use
880 #define max_t(type, x, y) \
882 __UNIQUE_ID(min1_), __UNIQUE_ID(min2_), \
886 * clamp_t - return a value clamped to a given range using a given type
887 * @type: the type of variable to use
888 * @val: current value
889 * @lo: minimum allowable value
890 * @hi: maximum allowable value
892 * This macro does no typechecking and uses temporary variables of type
893 * @type to make all the comparisons.
895 #define clamp_t(type, val, lo, hi) min_t(type, max_t(type, val, lo), hi)
898 * clamp_val - return a value clamped to a given range using val's type
899 * @val: current value
900 * @lo: minimum allowable value
901 * @hi: maximum allowable value
903 * This macro does no typechecking and uses temporary variables of whatever
904 * type the input argument @val is. This is useful when @val is an unsigned
905 * type and @lo and @hi are literals that will otherwise be assigned a signed
908 #define clamp_val(val, lo, hi) clamp_t(typeof(val), val, lo, hi)
912 * swap - swap values of @a and @b
917 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
920 * container_of - cast a member of a structure out to the containing structure
921 * @ptr: the pointer to the member.
922 * @type: the type of the container struct this is embedded in.
923 * @member: the name of the member within the struct.
926 #define container_of(ptr, type, member) ({ \
927 void *__mptr = (void *)(ptr); \
928 BUILD_BUG_ON_MSG(!__same_type(*(ptr), ((type *)0)->member) && \
929 !__same_type(*(ptr), void), \
930 "pointer type mismatch in container_of()"); \
931 ((type *)(__mptr - offsetof(type, member))); })
933 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
934 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
935 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
938 /* Permissions on a sysfs file: you didn't miss the 0 prefix did you? */
939 #define VERIFY_OCTAL_PERMISSIONS(perms) \
940 (BUILD_BUG_ON_ZERO((perms) < 0) + \
941 BUILD_BUG_ON_ZERO((perms) > 0777) + \
942 /* USER_READABLE >= GROUP_READABLE >= OTHER_READABLE */ \
943 BUILD_BUG_ON_ZERO((((perms) >> 6) & 4) < (((perms) >> 3) & 4)) + \
944 BUILD_BUG_ON_ZERO((((perms) >> 3) & 4) < ((perms) & 4)) + \
945 /* USER_WRITABLE >= GROUP_WRITABLE */ \
946 BUILD_BUG_ON_ZERO((((perms) >> 6) & 2) < (((perms) >> 3) & 2)) + \
947 /* OTHER_WRITABLE? Generally considered a bad idea. */ \
948 BUILD_BUG_ON_ZERO((perms) & 2) + \