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/dynamic_debug.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 STACK_MAGIC 0xdeadbeef
34 #define REPEAT_BYTE(x) ((~0ul / 0xff) * (x))
36 #define ALIGN(x, a) __ALIGN_KERNEL((x), (a))
37 #define __ALIGN_MASK(x, mask) __ALIGN_KERNEL_MASK((x), (mask))
38 #define PTR_ALIGN(p, a) ((typeof(p))ALIGN((unsigned long)(p), (a)))
39 #define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0)
41 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
44 * This looks more complex than it should be. But we need to
45 * get the type for the ~ right in round_down (it needs to be
46 * as wide as the result!), and we want to evaluate the macro
47 * arguments just once each.
49 #define __round_mask(x, y) ((__typeof__(x))((y)-1))
50 #define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1)
51 #define round_down(x, y) ((x) & ~__round_mask(x, y))
53 #define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
54 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
55 #define DIV_ROUND_UP_ULL(ll,d) \
56 ({ unsigned long long _tmp = (ll)+(d)-1; do_div(_tmp, d); _tmp; })
58 #if BITS_PER_LONG == 32
59 # define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP_ULL(ll, d)
61 # define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP(ll,d)
64 /* The `const' in roundup() prevents gcc-3.3 from calling __divdi3 */
65 #define roundup(x, y) ( \
67 const typeof(y) __y = y; \
68 (((x) + (__y - 1)) / __y) * __y; \
71 #define rounddown(x, y) ( \
73 typeof(x) __x = (x); \
79 * Divide positive or negative dividend by positive divisor and round
80 * to closest integer. Result is undefined for negative divisors and
81 * for negative dividends if the divisor variable type is unsigned.
83 #define DIV_ROUND_CLOSEST(x, divisor)( \
86 typeof(divisor) __d = divisor; \
87 (((typeof(x))-1) > 0 || \
88 ((typeof(divisor))-1) > 0 || (__x) > 0) ? \
89 (((__x) + ((__d) / 2)) / (__d)) : \
90 (((__x) - ((__d) / 2)) / (__d)); \
95 * Multiplies an integer by a fraction, while avoiding unnecessary
96 * overflow or loss of precision.
98 #define mult_frac(x, numer, denom)( \
100 typeof(x) quot = (x) / (denom); \
101 typeof(x) rem = (x) % (denom); \
102 (quot * (numer)) + ((rem * (numer)) / (denom)); \
107 #define _RET_IP_ (unsigned long)__builtin_return_address(0)
108 #define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; })
111 # include <asm/div64.h>
112 # define sector_div(a, b) do_div(a, b)
114 # define sector_div(n, b)( \
125 * upper_32_bits - return bits 32-63 of a number
126 * @n: the number we're accessing
128 * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress
129 * the "right shift count >= width of type" warning when that quantity is
132 #define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
135 * lower_32_bits - return bits 0-31 of a number
136 * @n: the number we're accessing
138 #define lower_32_bits(n) ((u32)(n))
144 #ifdef CONFIG_PREEMPT_VOLUNTARY
145 extern int _cond_resched(void);
146 # define might_resched() _cond_resched()
148 # define might_resched() do { } while (0)
151 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
152 void __might_sleep(const char *file, int line, int preempt_offset);
154 * might_sleep - annotation for functions that can sleep
156 * this macro will print a stack trace if it is executed in an atomic
157 * context (spinlock, irq-handler, ...).
159 * This is a useful debugging help to be able to catch problems early and not
160 * be bitten later when the calling function happens to sleep when it is not
163 # define might_sleep() \
164 do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
166 static inline void __might_sleep(const char *file, int line,
167 int preempt_offset) { }
168 # define might_sleep() do { might_resched(); } while (0)
171 #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
174 * abs() handles unsigned and signed longs, ints, shorts and chars. For all
175 * input types abs() returns a signed long.
176 * abs() should not be used for 64-bit types (s64, u64, long long) - use abs64()
181 if (sizeof(x) == sizeof(long)) { \
183 ret = (__x < 0) ? -__x : __x; \
186 ret = (__x < 0) ? -__x : __x; \
191 #define abs64(x) ({ \
193 (__x < 0) ? -__x : __x; \
196 #if defined(CONFIG_MMU) && \
197 (defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_DEBUG_ATOMIC_SLEEP))
198 void might_fault(void);
200 static inline void might_fault(void) { }
203 extern struct atomic_notifier_head panic_notifier_list;
204 extern long (*panic_blink)(int state);
206 void panic(const char *fmt, ...)
208 extern void oops_enter(void);
209 extern void oops_exit(void);
210 void print_oops_end_marker(void);
211 extern int oops_may_print(void);
212 void do_exit(long error_code)
214 void complete_and_exit(struct completion *, long)
217 /* Internal, do not use. */
218 int __must_check _kstrtoul(const char *s, unsigned int base, unsigned long *res);
219 int __must_check _kstrtol(const char *s, unsigned int base, long *res);
221 int __must_check kstrtoull(const char *s, unsigned int base, unsigned long long *res);
222 int __must_check kstrtoll(const char *s, unsigned int base, long long *res);
225 * kstrtoul - convert a string to an unsigned long
226 * @s: The start of the string. The string must be null-terminated, and may also
227 * include a single newline before its terminating null. The first character
228 * may also be a plus sign, but not a minus sign.
229 * @base: The number base to use. The maximum supported base is 16. If base is
230 * given as 0, then the base of the string is automatically detected with the
231 * conventional semantics - If it begins with 0x the number will be parsed as a
232 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be
233 * parsed as an octal number. Otherwise it will be parsed as a decimal.
234 * @res: Where to write the result of the conversion on success.
236 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
237 * Used as a replacement for the obsolete simple_strtoull. Return code must
240 static inline int __must_check kstrtoul(const char *s, unsigned int base, unsigned long *res)
243 * We want to shortcut function call, but
244 * __builtin_types_compatible_p(unsigned long, unsigned long long) = 0.
246 if (sizeof(unsigned long) == sizeof(unsigned long long) &&
247 __alignof__(unsigned long) == __alignof__(unsigned long long))
248 return kstrtoull(s, base, (unsigned long long *)res);
250 return _kstrtoul(s, base, res);
254 * kstrtol - convert a string to a long
255 * @s: The start of the string. The string must be null-terminated, and may also
256 * include a single newline before its terminating null. The first character
257 * may also be a plus sign or a minus sign.
258 * @base: The number base to use. The maximum supported base is 16. If base is
259 * given as 0, then the base of the string is automatically detected with the
260 * conventional semantics - If it begins with 0x the number will be parsed as a
261 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be
262 * parsed as an octal number. Otherwise it will be parsed as a decimal.
263 * @res: Where to write the result of the conversion on success.
265 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
266 * Used as a replacement for the obsolete simple_strtoull. Return code must
269 static inline int __must_check kstrtol(const char *s, unsigned int base, long *res)
272 * We want to shortcut function call, but
273 * __builtin_types_compatible_p(long, long long) = 0.
275 if (sizeof(long) == sizeof(long long) &&
276 __alignof__(long) == __alignof__(long long))
277 return kstrtoll(s, base, (long long *)res);
279 return _kstrtol(s, base, res);
282 int __must_check kstrtouint(const char *s, unsigned int base, unsigned int *res);
283 int __must_check kstrtoint(const char *s, unsigned int base, int *res);
285 static inline int __must_check kstrtou64(const char *s, unsigned int base, u64 *res)
287 return kstrtoull(s, base, res);
290 static inline int __must_check kstrtos64(const char *s, unsigned int base, s64 *res)
292 return kstrtoll(s, base, res);
295 static inline int __must_check kstrtou32(const char *s, unsigned int base, u32 *res)
297 return kstrtouint(s, base, res);
300 static inline int __must_check kstrtos32(const char *s, unsigned int base, s32 *res)
302 return kstrtoint(s, base, res);
305 int __must_check kstrtou16(const char *s, unsigned int base, u16 *res);
306 int __must_check kstrtos16(const char *s, unsigned int base, s16 *res);
307 int __must_check kstrtou8(const char *s, unsigned int base, u8 *res);
308 int __must_check kstrtos8(const char *s, unsigned int base, s8 *res);
310 int __must_check kstrtoull_from_user(const char __user *s, size_t count, unsigned int base, unsigned long long *res);
311 int __must_check kstrtoll_from_user(const char __user *s, size_t count, unsigned int base, long long *res);
312 int __must_check kstrtoul_from_user(const char __user *s, size_t count, unsigned int base, unsigned long *res);
313 int __must_check kstrtol_from_user(const char __user *s, size_t count, unsigned int base, long *res);
314 int __must_check kstrtouint_from_user(const char __user *s, size_t count, unsigned int base, unsigned int *res);
315 int __must_check kstrtoint_from_user(const char __user *s, size_t count, unsigned int base, int *res);
316 int __must_check kstrtou16_from_user(const char __user *s, size_t count, unsigned int base, u16 *res);
317 int __must_check kstrtos16_from_user(const char __user *s, size_t count, unsigned int base, s16 *res);
318 int __must_check kstrtou8_from_user(const char __user *s, size_t count, unsigned int base, u8 *res);
319 int __must_check kstrtos8_from_user(const char __user *s, size_t count, unsigned int base, s8 *res);
321 static inline int __must_check kstrtou64_from_user(const char __user *s, size_t count, unsigned int base, u64 *res)
323 return kstrtoull_from_user(s, count, base, res);
326 static inline int __must_check kstrtos64_from_user(const char __user *s, size_t count, unsigned int base, s64 *res)
328 return kstrtoll_from_user(s, count, base, res);
331 static inline int __must_check kstrtou32_from_user(const char __user *s, size_t count, unsigned int base, u32 *res)
333 return kstrtouint_from_user(s, count, base, res);
336 static inline int __must_check kstrtos32_from_user(const char __user *s, size_t count, unsigned int base, s32 *res)
338 return kstrtoint_from_user(s, count, base, res);
341 /* Obsolete, do not use. Use kstrto<foo> instead */
343 extern unsigned long simple_strtoul(const char *,char **,unsigned int);
344 extern long simple_strtol(const char *,char **,unsigned int);
345 extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
346 extern long long simple_strtoll(const char *,char **,unsigned int);
347 #define strict_strtoul kstrtoul
348 #define strict_strtol kstrtol
349 #define strict_strtoull kstrtoull
350 #define strict_strtoll kstrtoll
352 extern int num_to_str(char *buf, int size, unsigned long long num);
354 /* lib/printf utilities */
356 extern __printf(2, 3) int sprintf(char *buf, const char * fmt, ...);
357 extern __printf(2, 0) int vsprintf(char *buf, const char *, va_list);
358 extern __printf(3, 4)
359 int snprintf(char *buf, size_t size, const char *fmt, ...);
360 extern __printf(3, 0)
361 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args);
362 extern __printf(3, 4)
363 int scnprintf(char *buf, size_t size, const char *fmt, ...);
364 extern __printf(3, 0)
365 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args);
366 extern __printf(2, 3)
367 char *kasprintf(gfp_t gfp, const char *fmt, ...);
368 extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args);
371 int sscanf(const char *, const char *, ...);
373 int vsscanf(const char *, const char *, va_list);
375 extern int get_option(char **str, int *pint);
376 extern char *get_options(const char *str, int nints, int *ints);
377 extern unsigned long long memparse(const char *ptr, char **retptr);
379 extern int core_kernel_text(unsigned long addr);
380 extern int core_kernel_data(unsigned long addr);
381 extern int __kernel_text_address(unsigned long addr);
382 extern int kernel_text_address(unsigned long addr);
383 extern int func_ptr_is_kernel_text(void *ptr);
386 extern struct pid *session_of_pgrp(struct pid *pgrp);
388 unsigned long int_sqrt(unsigned long);
390 extern void bust_spinlocks(int yes);
391 extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */
392 extern int panic_timeout;
393 extern int panic_on_oops;
394 extern int panic_on_unrecovered_nmi;
395 extern int panic_on_io_nmi;
396 extern int sysctl_panic_on_stackoverflow;
398 * Only to be used by arch init code. If the user over-wrote the default
399 * CONFIG_PANIC_TIMEOUT, honor it.
401 static inline void set_arch_panic_timeout(int timeout, int arch_default_timeout)
403 if (panic_timeout == arch_default_timeout)
404 panic_timeout = timeout;
406 extern const char *print_tainted(void);
409 LOCKDEP_NOW_UNRELIABLE
411 extern void add_taint(unsigned flag, enum lockdep_ok);
412 extern int test_taint(unsigned flag);
413 extern unsigned long get_taint(void);
414 extern int root_mountflags;
416 extern bool early_boot_irqs_disabled;
418 /* Values used for system_state */
419 extern enum system_states {
427 #define TAINT_PROPRIETARY_MODULE 0
428 #define TAINT_FORCED_MODULE 1
429 #define TAINT_UNSAFE_SMP 2
430 #define TAINT_FORCED_RMMOD 3
431 #define TAINT_MACHINE_CHECK 4
432 #define TAINT_BAD_PAGE 5
435 #define TAINT_OVERRIDDEN_ACPI_TABLE 8
437 #define TAINT_CRAP 10
438 #define TAINT_FIRMWARE_WORKAROUND 11
439 #define TAINT_OOT_MODULE 12
441 extern const char hex_asc[];
442 #define hex_asc_lo(x) hex_asc[((x) & 0x0f)]
443 #define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4]
445 static inline char *hex_byte_pack(char *buf, u8 byte)
447 *buf++ = hex_asc_hi(byte);
448 *buf++ = hex_asc_lo(byte);
452 extern const char hex_asc_upper[];
453 #define hex_asc_upper_lo(x) hex_asc_upper[((x) & 0x0f)]
454 #define hex_asc_upper_hi(x) hex_asc_upper[((x) & 0xf0) >> 4]
456 static inline char *hex_byte_pack_upper(char *buf, u8 byte)
458 *buf++ = hex_asc_upper_hi(byte);
459 *buf++ = hex_asc_upper_lo(byte);
463 static inline char * __deprecated pack_hex_byte(char *buf, u8 byte)
465 return hex_byte_pack(buf, byte);
468 extern int hex_to_bin(char ch);
469 extern int __must_check hex2bin(u8 *dst, const char *src, size_t count);
471 int mac_pton(const char *s, u8 *mac);
474 * General tracing related utility functions - trace_printk(),
475 * tracing_on/tracing_off and tracing_start()/tracing_stop
477 * Use tracing_on/tracing_off when you want to quickly turn on or off
478 * tracing. It simply enables or disables the recording of the trace events.
479 * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
480 * file, which gives a means for the kernel and userspace to interact.
481 * Place a tracing_off() in the kernel where you want tracing to end.
482 * From user space, examine the trace, and then echo 1 > tracing_on
483 * to continue tracing.
485 * tracing_stop/tracing_start has slightly more overhead. It is used
486 * by things like suspend to ram where disabling the recording of the
487 * trace is not enough, but tracing must actually stop because things
488 * like calling smp_processor_id() may crash the system.
490 * Most likely, you want to use tracing_on/tracing_off.
492 #ifdef CONFIG_RING_BUFFER
493 /* trace_off_permanent stops recording with no way to bring it back */
494 void tracing_off_permanent(void);
496 static inline void tracing_off_permanent(void) { }
499 enum ftrace_dump_mode {
505 #ifdef CONFIG_TRACING
506 void tracing_on(void);
507 void tracing_off(void);
508 int tracing_is_on(void);
509 void tracing_snapshot(void);
510 void tracing_snapshot_alloc(void);
512 extern void tracing_start(void);
513 extern void tracing_stop(void);
515 static inline __printf(1, 2)
516 void ____trace_printk_check_format(const char *fmt, ...)
519 #define __trace_printk_check_format(fmt, args...) \
522 ____trace_printk_check_format(fmt, ##args); \
526 * trace_printk - printf formatting in the ftrace buffer
527 * @fmt: the printf format for printing
529 * Note: __trace_printk is an internal function for trace_printk and
530 * the @ip is passed in via the trace_printk macro.
532 * This function allows a kernel developer to debug fast path sections
533 * that printk is not appropriate for. By scattering in various
534 * printk like tracing in the code, a developer can quickly see
535 * where problems are occurring.
537 * This is intended as a debugging tool for the developer only.
538 * Please refrain from leaving trace_printks scattered around in
539 * your code. (Extra memory is used for special buffers that are
540 * allocated when trace_printk() is used)
542 * A little optization trick is done here. If there's only one
543 * argument, there's no need to scan the string for printf formats.
544 * The trace_puts() will suffice. But how can we take advantage of
545 * using trace_puts() when trace_printk() has only one argument?
546 * By stringifying the args and checking the size we can tell
547 * whether or not there are args. __stringify((__VA_ARGS__)) will
548 * turn into "()\0" with a size of 3 when there are no args, anything
549 * else will be bigger. All we need to do is define a string to this,
550 * and then take its size and compare to 3. If it's bigger, use
551 * do_trace_printk() otherwise, optimize it to trace_puts(). Then just
552 * let gcc optimize the rest.
555 #define trace_printk(fmt, ...) \
557 char _______STR[] = __stringify((__VA_ARGS__)); \
558 if (sizeof(_______STR) > 3) \
559 do_trace_printk(fmt, ##__VA_ARGS__); \
564 #define do_trace_printk(fmt, args...) \
566 static const char *trace_printk_fmt \
567 __attribute__((section("__trace_printk_fmt"))) = \
568 __builtin_constant_p(fmt) ? fmt : NULL; \
570 __trace_printk_check_format(fmt, ##args); \
572 if (__builtin_constant_p(fmt)) \
573 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \
575 __trace_printk(_THIS_IP_, fmt, ##args); \
578 extern __printf(2, 3)
579 int __trace_bprintk(unsigned long ip, const char *fmt, ...);
581 extern __printf(2, 3)
582 int __trace_printk(unsigned long ip, const char *fmt, ...);
585 * trace_puts - write a string into the ftrace buffer
586 * @str: the string to record
588 * Note: __trace_bputs is an internal function for trace_puts and
589 * the @ip is passed in via the trace_puts macro.
591 * This is similar to trace_printk() but is made for those really fast
592 * paths that a developer wants the least amount of "Heisenbug" affects,
593 * where the processing of the print format is still too much.
595 * This function allows a kernel developer to debug fast path sections
596 * that printk is not appropriate for. By scattering in various
597 * printk like tracing in the code, a developer can quickly see
598 * where problems are occurring.
600 * This is intended as a debugging tool for the developer only.
601 * Please refrain from leaving trace_puts scattered around in
602 * your code. (Extra memory is used for special buffers that are
603 * allocated when trace_puts() is used)
605 * Returns: 0 if nothing was written, positive # if string was.
606 * (1 when __trace_bputs is used, strlen(str) when __trace_puts is used)
609 #define trace_puts(str) ({ \
610 static const char *trace_printk_fmt \
611 __attribute__((section("__trace_printk_fmt"))) = \
612 __builtin_constant_p(str) ? str : NULL; \
614 if (__builtin_constant_p(str)) \
615 __trace_bputs(_THIS_IP_, trace_printk_fmt); \
617 __trace_puts(_THIS_IP_, str, strlen(str)); \
619 extern int __trace_bputs(unsigned long ip, const char *str);
620 extern int __trace_puts(unsigned long ip, const char *str, int size);
622 extern void trace_dump_stack(int skip);
625 * The double __builtin_constant_p is because gcc will give us an error
626 * if we try to allocate the static variable to fmt if it is not a
627 * constant. Even with the outer if statement.
629 #define ftrace_vprintk(fmt, vargs) \
631 if (__builtin_constant_p(fmt)) { \
632 static const char *trace_printk_fmt \
633 __attribute__((section("__trace_printk_fmt"))) = \
634 __builtin_constant_p(fmt) ? fmt : NULL; \
636 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \
638 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \
642 __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap);
645 __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap);
647 extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode);
649 static inline void tracing_start(void) { }
650 static inline void tracing_stop(void) { }
651 static inline void trace_dump_stack(int skip) { }
653 static inline void tracing_on(void) { }
654 static inline void tracing_off(void) { }
655 static inline int tracing_is_on(void) { return 0; }
656 static inline void tracing_snapshot(void) { }
657 static inline void tracing_snapshot_alloc(void) { }
659 static inline __printf(1, 2)
660 int trace_printk(const char *fmt, ...)
665 ftrace_vprintk(const char *fmt, va_list ap)
669 static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
670 #endif /* CONFIG_TRACING */
673 * min()/max()/clamp() macros that also do
674 * strict type-checking.. See the
675 * "unnecessary" pointer comparison.
677 #define min(x, y) ({ \
678 typeof(x) _min1 = (x); \
679 typeof(y) _min2 = (y); \
680 (void) (&_min1 == &_min2); \
681 _min1 < _min2 ? _min1 : _min2; })
683 #define max(x, y) ({ \
684 typeof(x) _max1 = (x); \
685 typeof(y) _max2 = (y); \
686 (void) (&_max1 == &_max2); \
687 _max1 > _max2 ? _max1 : _max2; })
689 #define min3(x, y, z) ({ \
690 typeof(x) _min1 = (x); \
691 typeof(y) _min2 = (y); \
692 typeof(z) _min3 = (z); \
693 (void) (&_min1 == &_min2); \
694 (void) (&_min1 == &_min3); \
695 _min1 < _min2 ? (_min1 < _min3 ? _min1 : _min3) : \
696 (_min2 < _min3 ? _min2 : _min3); })
698 #define max3(x, y, z) ({ \
699 typeof(x) _max1 = (x); \
700 typeof(y) _max2 = (y); \
701 typeof(z) _max3 = (z); \
702 (void) (&_max1 == &_max2); \
703 (void) (&_max1 == &_max3); \
704 _max1 > _max2 ? (_max1 > _max3 ? _max1 : _max3) : \
705 (_max2 > _max3 ? _max2 : _max3); })
708 * min_not_zero - return the minimum that is _not_ zero, unless both are zero
712 #define min_not_zero(x, y) ({ \
713 typeof(x) __x = (x); \
714 typeof(y) __y = (y); \
715 __x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); })
718 * clamp - return a value clamped to a given range with strict typechecking
719 * @val: current value
720 * @min: minimum allowable value
721 * @max: maximum allowable value
723 * This macro does strict typechecking of min/max to make sure they are of the
724 * same type as val. See the unnecessary pointer comparisons.
726 #define clamp(val, min, max) ({ \
727 typeof(val) __val = (val); \
728 typeof(min) __min = (min); \
729 typeof(max) __max = (max); \
730 (void) (&__val == &__min); \
731 (void) (&__val == &__max); \
732 __val = __val < __min ? __min: __val; \
733 __val > __max ? __max: __val; })
736 * ..and if you can't take the strict
737 * types, you can specify one yourself.
739 * Or not use min/max/clamp at all, of course.
741 #define min_t(type, x, y) ({ \
744 __min1 < __min2 ? __min1: __min2; })
746 #define max_t(type, x, y) ({ \
749 __max1 > __max2 ? __max1: __max2; })
752 * clamp_t - return a value clamped to a given range using a given type
753 * @type: the type of variable to use
754 * @val: current value
755 * @min: minimum allowable value
756 * @max: maximum allowable value
758 * This macro does no typechecking and uses temporary variables of type
759 * 'type' to make all the comparisons.
761 #define clamp_t(type, val, min, max) ({ \
762 type __val = (val); \
763 type __min = (min); \
764 type __max = (max); \
765 __val = __val < __min ? __min: __val; \
766 __val > __max ? __max: __val; })
769 * clamp_val - return a value clamped to a given range using val's type
770 * @val: current value
771 * @min: minimum allowable value
772 * @max: maximum allowable value
774 * This macro does no typechecking and uses temporary variables of whatever
775 * type the input argument 'val' is. This is useful when val is an unsigned
776 * type and min and max are literals that will otherwise be assigned a signed
779 #define clamp_val(val, min, max) ({ \
780 typeof(val) __val = (val); \
781 typeof(val) __min = (min); \
782 typeof(val) __max = (max); \
783 __val = __val < __min ? __min: __val; \
784 __val > __max ? __max: __val; })
788 * swap - swap value of @a and @b
791 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
794 * container_of - cast a member of a structure out to the containing structure
795 * @ptr: the pointer to the member.
796 * @type: the type of the container struct this is embedded in.
797 * @member: the name of the member within the struct.
800 #define container_of(ptr, type, member) ({ \
801 const typeof( ((type *)0)->member ) *__mptr = (ptr); \
802 (type *)( (char *)__mptr - offsetof(type,member) );})
804 /* Trap pasters of __FUNCTION__ at compile-time */
805 #define __FUNCTION__ (__func__)
807 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
808 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
809 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD