1 /*-
2  * Copyright (c) 2010 Isilon Systems, Inc.
3  * Copyright (c) 2010 iX Systems, Inc.
4  * Copyright (c) 2010 Panasas, Inc.
5  * Copyright (c) 2013-2016 Mellanox Technologies, Ltd.
6  * Copyright (c) 2014-2015 François Tigeot
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice unmodified, this list of conditions, and the following
14  *    disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29  */
30 #ifndef	_LINUXKPI_LINUX_KERNEL_H_
31 #define	_LINUXKPI_LINUX_KERNEL_H_
32 
33 #include <sys/types.h>
34 #include <sys/systm.h>
35 #include <sys/param.h>
36 #include <sys/libkern.h>
37 #include <sys/stat.h>
38 #include <sys/smp.h>
39 #include <sys/stddef.h>
40 #include <sys/syslog.h>
41 #include <sys/time.h>
42 
43 #include <linux/bitops.h>
44 #include <linux/compiler.h>
45 #include <linux/stringify.h>
46 #include <linux/errno.h>
47 #include <linux/sched.h>
48 #include <linux/types.h>
49 #include <linux/typecheck.h>
50 #include <linux/jiffies.h>
51 #include <linux/log2.h>
52 #include <linux/kconfig.h>
53 
54 #include <asm/byteorder.h>
55 #include <asm/cpufeature.h>
56 #include <asm/processor.h>
57 #include <asm/uaccess.h>
58 
59 #include <linux/stdarg.h>
60 
61 #define KERN_CONT       ""
62 #define	KERN_EMERG	"<0>"
63 #define	KERN_ALERT	"<1>"
64 #define	KERN_CRIT	"<2>"
65 #define	KERN_ERR	"<3>"
66 #define	KERN_WARNING	"<4>"
67 #define	KERN_NOTICE	"<5>"
68 #define	KERN_INFO	"<6>"
69 #define	KERN_DEBUG	"<7>"
70 
71 #define	U8_MAX		((u8)~0U)
72 #define	S8_MAX		((s8)(U8_MAX >> 1))
73 #define	S8_MIN		((s8)(-S8_MAX - 1))
74 #define	U16_MAX		((u16)~0U)
75 #define	S16_MAX		((s16)(U16_MAX >> 1))
76 #define	S16_MIN		((s16)(-S16_MAX - 1))
77 #define	U32_MAX		((u32)~0U)
78 #define	S32_MAX		((s32)(U32_MAX >> 1))
79 #define	S32_MIN		((s32)(-S32_MAX - 1))
80 #define	U64_MAX		((u64)~0ULL)
81 #define	S64_MAX		((s64)(U64_MAX >> 1))
82 #define	S64_MIN		((s64)(-S64_MAX - 1))
83 
84 #define	S8_C(x)  x
85 #define	U8_C(x)  x ## U
86 #define	S16_C(x) x
87 #define	U16_C(x) x ## U
88 #define	S32_C(x) x
89 #define	U32_C(x) x ## U
90 #define	S64_C(x) x ## LL
91 #define	U64_C(x) x ## ULL
92 
93 /*
94  * BUILD_BUG_ON() can happen inside functions where _Static_assert() does not
95  * seem to work.  Use old-schoold-ish CTASSERT from before commit
96  * a3085588a88fa58eb5b1eaae471999e1995a29cf but also make sure we do not
97  * end up with an unused typedef or variable. The compiler should optimise
98  * it away entirely.
99  */
100 #define	_O_CTASSERT(x)		_O__CTASSERT(x, __LINE__)
101 #define	_O__CTASSERT(x, y)	_O___CTASSERT(x, y)
102 #define	_O___CTASSERT(x, y)	while (0) { \
103     typedef char __unused __assert_line_ ## y[(x) ? 1 : -1]; \
104     __assert_line_ ## y _x; \
105     _x[0] = '\0'; \
106 }
107 
108 #define	BUILD_BUG()			do { CTASSERT(0); } while (0)
109 #define	BUILD_BUG_ON(x)			do { _O_CTASSERT(!(x)) } while (0)
110 #define	BUILD_BUG_ON_MSG(x, msg)	BUILD_BUG_ON(x)
111 #define	BUILD_BUG_ON_NOT_POWER_OF_2(x)	BUILD_BUG_ON(!powerof2(x))
112 #define	BUILD_BUG_ON_INVALID(expr)	while (0) { (void)(expr); }
113 #define	BUILD_BUG_ON_ZERO(x)	((int)sizeof(struct { int:-((x) != 0); }))
114 
115 #define	BUG()			panic("BUG at %s:%d", __FILE__, __LINE__)
116 #define	BUG_ON(cond)		do {				\
117 	if (cond) {						\
118 		panic("BUG ON %s failed at %s:%d",		\
119 		    __stringify(cond), __FILE__, __LINE__);	\
120 	}							\
121 } while (0)
122 
123 extern int linuxkpi_warn_dump_stack;
124 #define	WARN_ON(cond) ({					\
125 	bool __ret = (cond);					\
126 	if (__ret) {						\
127 		printf("WARNING %s failed at %s:%d\n",		\
128 		    __stringify(cond), __FILE__, __LINE__);	\
129 		if (linuxkpi_warn_dump_stack)				\
130 			linux_dump_stack();				\
131 	}								\
132 	unlikely(__ret);						\
133 })
134 
135 #define	WARN_ON_SMP(cond)	WARN_ON(cond)
136 
137 #define	WARN_ON_ONCE(cond) ({					\
138 	static bool __warn_on_once;				\
139 	bool __ret = (cond);					\
140 	if (__ret && !__warn_on_once) {				\
141 		__warn_on_once = 1;				\
142 		printf("WARNING %s failed at %s:%d\n",		\
143 		    __stringify(cond), __FILE__, __LINE__);	\
144 		if (linuxkpi_warn_dump_stack)				\
145 			linux_dump_stack();				\
146 	}								\
147 	unlikely(__ret);						\
148 })
149 
150 #define	oops_in_progress	SCHEDULER_STOPPED()
151 
152 #undef	ALIGN
153 #define	ALIGN(x, y)		roundup2((x), (y))
154 #define	ALIGN_DOWN(x, y)	rounddown2(x, y)
155 #undef PTR_ALIGN
156 #define	PTR_ALIGN(p, a)		((__typeof(p))ALIGN((uintptr_t)(p), (a)))
157 #define	IS_ALIGNED(x, a)	(((x) & ((__typeof(x))(a) - 1)) == 0)
158 #define	DIV_ROUND_UP(x, n)	howmany(x, n)
159 #define	__KERNEL_DIV_ROUND_UP(x, n)	howmany(x, n)
160 #define	DIV_ROUND_UP_ULL(x, n)	DIV_ROUND_UP((unsigned long long)(x), (n))
161 #define	DIV_ROUND_DOWN_ULL(x, n) (((unsigned long long)(x) / (n)) * (n))
162 #define	FIELD_SIZEOF(t, f)	sizeof(((t *)0)->f)
163 
164 #define	printk(...)		printf(__VA_ARGS__)
165 #define	vprintk(f, a)		vprintf(f, a)
166 
167 #define	asm			__asm
168 
169 extern void linux_dump_stack(void);
170 #define	dump_stack()		linux_dump_stack()
171 
172 struct va_format {
173 	const char *fmt;
174 	va_list *va;
175 };
176 
177 static inline int
178 vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
179 {
180 	ssize_t ssize = size;
181 	int i;
182 
183 	i = vsnprintf(buf, size, fmt, args);
184 
185 	return ((i >= ssize) ? (ssize - 1) : i);
186 }
187 
188 static inline int
189 scnprintf(char *buf, size_t size, const char *fmt, ...)
190 {
191 	va_list args;
192 	int i;
193 
194 	va_start(args, fmt);
195 	i = vscnprintf(buf, size, fmt, args);
196 	va_end(args);
197 
198 	return (i);
199 }
200 
201 /*
202  * The "pr_debug()" and "pr_devel()" macros should produce zero code
203  * unless DEBUG is defined:
204  */
205 #ifdef DEBUG
206 extern int linuxkpi_debug;
207 #define pr_debug(fmt, ...)					\
208 	do {							\
209 		if (linuxkpi_debug)				\
210 			log(LOG_DEBUG, fmt, ##__VA_ARGS__);	\
211 	} while (0)
212 #define pr_devel(fmt, ...) \
213 	log(LOG_DEBUG, pr_fmt(fmt), ##__VA_ARGS__)
214 #else
215 #define pr_debug(fmt, ...) \
216 	({ if (0) log(LOG_DEBUG, fmt, ##__VA_ARGS__); 0; })
217 #define pr_devel(fmt, ...) \
218 	({ if (0) log(LOG_DEBUG, pr_fmt(fmt), ##__VA_ARGS__); 0; })
219 #endif
220 
221 #ifndef pr_fmt
222 #define pr_fmt(fmt) fmt
223 #endif
224 
225 /*
226  * Print a one-time message (analogous to WARN_ONCE() et al):
227  */
228 #define printk_once(...) do {			\
229 	static bool __print_once;		\
230 						\
231 	if (!__print_once) {			\
232 		__print_once = true;		\
233 		printk(__VA_ARGS__);		\
234 	}					\
235 } while (0)
236 
237 /*
238  * Log a one-time message (analogous to WARN_ONCE() et al):
239  */
240 #define log_once(level,...) do {		\
241 	static bool __log_once;			\
242 						\
243 	if (unlikely(!__log_once)) {		\
244 		__log_once = true;		\
245 		log(level, __VA_ARGS__);	\
246 	}					\
247 } while (0)
248 
249 #define pr_emerg(fmt, ...) \
250 	log(LOG_EMERG, pr_fmt(fmt), ##__VA_ARGS__)
251 #define pr_alert(fmt, ...) \
252 	log(LOG_ALERT, pr_fmt(fmt), ##__VA_ARGS__)
253 #define pr_crit(fmt, ...) \
254 	log(LOG_CRIT, pr_fmt(fmt), ##__VA_ARGS__)
255 #define pr_err(fmt, ...) \
256 	log(LOG_ERR, pr_fmt(fmt), ##__VA_ARGS__)
257 #define pr_err_once(fmt, ...) \
258 	log_once(LOG_ERR, pr_fmt(fmt), ##__VA_ARGS__)
259 #define pr_warning(fmt, ...) \
260 	log(LOG_WARNING, pr_fmt(fmt), ##__VA_ARGS__)
261 #define pr_warn(...) \
262 	pr_warning(__VA_ARGS__)
263 #define pr_warn_once(fmt, ...) \
264 	log_once(LOG_WARNING, pr_fmt(fmt), ##__VA_ARGS__)
265 #define pr_notice(fmt, ...) \
266 	log(LOG_NOTICE, pr_fmt(fmt), ##__VA_ARGS__)
267 #define pr_info(fmt, ...) \
268 	log(LOG_INFO, pr_fmt(fmt), ##__VA_ARGS__)
269 #define pr_info_once(fmt, ...) \
270 	log_once(LOG_INFO, pr_fmt(fmt), ##__VA_ARGS__)
271 #define pr_cont(fmt, ...) \
272 	printk(KERN_CONT fmt, ##__VA_ARGS__)
273 #define	pr_warn_ratelimited(...) do {		\
274 	static linux_ratelimit_t __ratelimited;	\
275 	if (linux_ratelimited(&__ratelimited))	\
276 		pr_warning(__VA_ARGS__);	\
277 } while (0)
278 
279 #ifndef WARN
280 #define	WARN(condition, ...) ({			\
281 	bool __ret_warn_on = (condition);	\
282 	if (unlikely(__ret_warn_on))		\
283 		pr_warning(__VA_ARGS__);	\
284 	unlikely(__ret_warn_on);		\
285 })
286 #endif
287 
288 #ifndef WARN_ONCE
289 #define	WARN_ONCE(condition, ...) ({		\
290 	bool __ret_warn_on = (condition);	\
291 	if (unlikely(__ret_warn_on))		\
292 		pr_warn_once(__VA_ARGS__);	\
293 	unlikely(__ret_warn_on);		\
294 })
295 #endif
296 
297 #define container_of(ptr, type, member)				\
298 ({								\
299 	const __typeof(((type *)0)->member) *__p = (ptr);	\
300 	(type *)((uintptr_t)__p - offsetof(type, member));	\
301 })
302 
303 #define	ARRAY_SIZE(x)	(sizeof(x) / sizeof((x)[0]))
304 
305 #define	u64_to_user_ptr(val)	((void *)(uintptr_t)(val))
306 
307 #define _RET_IP_		__builtin_return_address(0)
308 
309 static inline unsigned long long
310 simple_strtoull(const char *cp, char **endp, unsigned int base)
311 {
312 	return (strtouq(cp, endp, base));
313 }
314 
315 static inline long long
316 simple_strtoll(const char *cp, char **endp, unsigned int base)
317 {
318 	return (strtoq(cp, endp, base));
319 }
320 
321 static inline unsigned long
322 simple_strtoul(const char *cp, char **endp, unsigned int base)
323 {
324 	return (strtoul(cp, endp, base));
325 }
326 
327 static inline long
328 simple_strtol(const char *cp, char **endp, unsigned int base)
329 {
330 	return (strtol(cp, endp, base));
331 }
332 
333 static inline int
334 kstrtoul(const char *cp, unsigned int base, unsigned long *res)
335 {
336 	char *end;
337 
338 	*res = strtoul(cp, &end, base);
339 
340 	/* skip newline character, if any */
341 	if (*end == '\n')
342 		end++;
343 	if (*cp == 0 || *end != 0)
344 		return (-EINVAL);
345 	return (0);
346 }
347 
348 static inline int
349 kstrtol(const char *cp, unsigned int base, long *res)
350 {
351 	char *end;
352 
353 	*res = strtol(cp, &end, base);
354 
355 	/* skip newline character, if any */
356 	if (*end == '\n')
357 		end++;
358 	if (*cp == 0 || *end != 0)
359 		return (-EINVAL);
360 	return (0);
361 }
362 
363 static inline int
364 kstrtoint(const char *cp, unsigned int base, int *res)
365 {
366 	char *end;
367 	long temp;
368 
369 	*res = temp = strtol(cp, &end, base);
370 
371 	/* skip newline character, if any */
372 	if (*end == '\n')
373 		end++;
374 	if (*cp == 0 || *end != 0)
375 		return (-EINVAL);
376 	if (temp != (int)temp)
377 		return (-ERANGE);
378 	return (0);
379 }
380 
381 static inline int
382 kstrtouint(const char *cp, unsigned int base, unsigned int *res)
383 {
384 	char *end;
385 	unsigned long temp;
386 
387 	*res = temp = strtoul(cp, &end, base);
388 
389 	/* skip newline character, if any */
390 	if (*end == '\n')
391 		end++;
392 	if (*cp == 0 || *end != 0)
393 		return (-EINVAL);
394 	if (temp != (unsigned int)temp)
395 		return (-ERANGE);
396 	return (0);
397 }
398 
399 static inline int
400 kstrtou8(const char *cp, unsigned int base, u8 *res)
401 {
402 	char *end;
403 	unsigned long temp;
404 
405 	*res = temp = strtoul(cp, &end, base);
406 
407 	/* skip newline character, if any */
408 	if (*end == '\n')
409 		end++;
410 	if (*cp == 0 || *end != 0)
411 		return (-EINVAL);
412 	if (temp != (u8)temp)
413 		return (-ERANGE);
414 	return (0);
415 }
416 
417 static inline int
418 kstrtou16(const char *cp, unsigned int base, u16 *res)
419 {
420 	char *end;
421 	unsigned long temp;
422 
423 	*res = temp = strtoul(cp, &end, base);
424 
425 	/* skip newline character, if any */
426 	if (*end == '\n')
427 		end++;
428 	if (*cp == 0 || *end != 0)
429 		return (-EINVAL);
430 	if (temp != (u16)temp)
431 		return (-ERANGE);
432 	return (0);
433 }
434 
435 static inline int
436 kstrtou32(const char *cp, unsigned int base, u32 *res)
437 {
438 
439 	return (kstrtouint(cp, base, res));
440 }
441 
442 static inline int
443 kstrtou64(const char *cp, unsigned int base, u64 *res)
444 {
445        char *end;
446 
447        *res = strtouq(cp, &end, base);
448 
449        /* skip newline character, if any */
450        if (*end == '\n')
451                end++;
452        if (*cp == 0 || *end != 0)
453                return (-EINVAL);
454        return (0);
455 }
456 
457 static inline int
458 kstrtoull(const char *cp, unsigned int base, unsigned long long *res)
459 {
460 	return (kstrtou64(cp, base, (u64 *)res));
461 }
462 
463 static inline int
464 kstrtobool(const char *s, bool *res)
465 {
466 	int len;
467 
468 	if (s == NULL || (len = strlen(s)) == 0 || res == NULL)
469 		return (-EINVAL);
470 
471 	/* skip newline character, if any */
472 	if (s[len - 1] == '\n')
473 		len--;
474 
475 	if (len == 1 && strchr("yY1", s[0]) != NULL)
476 		*res = true;
477 	else if (len == 1 && strchr("nN0", s[0]) != NULL)
478 		*res = false;
479 	else if (strncasecmp("on", s, len) == 0)
480 		*res = true;
481 	else if (strncasecmp("off", s, len) == 0)
482 		*res = false;
483 	else
484 		return (-EINVAL);
485 
486 	return (0);
487 }
488 
489 static inline int
490 kstrtobool_from_user(const char __user *s, size_t count, bool *res)
491 {
492 	char buf[8] = {};
493 
494 	if (count > (sizeof(buf) - 1))
495 		count = (sizeof(buf) - 1);
496 
497 	if (copy_from_user(buf, s, count))
498 		return (-EFAULT);
499 
500 	return (kstrtobool(buf, res));
501 }
502 
503 static inline int
504 kstrtoint_from_user(const char __user *s, size_t count, unsigned int base,
505     int *p)
506 {
507 	char buf[36] = {};
508 
509 	if (count > (sizeof(buf) - 1))
510 		count = (sizeof(buf) - 1);
511 
512 	if (copy_from_user(buf, s, count))
513 		return (-EFAULT);
514 
515 	return (kstrtoint(buf, base, p));
516 }
517 
518 static inline int
519 kstrtouint_from_user(const char __user *s, size_t count, unsigned int base,
520     unsigned int *p)
521 {
522 	char buf[36] = {};
523 
524 	if (count > (sizeof(buf) - 1))
525 		count = (sizeof(buf) - 1);
526 
527 	if (copy_from_user(buf, s, count))
528 		return (-EFAULT);
529 
530 	return (kstrtouint(buf, base, p));
531 }
532 
533 static inline int
534 kstrtou32_from_user(const char __user *s, size_t count, unsigned int base,
535     unsigned int *p)
536 {
537 
538 	return (kstrtouint_from_user(s, count, base, p));
539 }
540 
541 static inline int
542 kstrtou8_from_user(const char __user *s, size_t count, unsigned int base,
543     u8 *p)
544 {
545 	char buf[8] = {};
546 
547 	if (count > (sizeof(buf) - 1))
548 		count = (sizeof(buf) - 1);
549 
550 	if (copy_from_user(buf, s, count))
551 		return (-EFAULT);
552 
553 	return (kstrtou8(buf, base, p));
554 }
555 
556 #define min(x, y)	((x) < (y) ? (x) : (y))
557 #define max(x, y)	((x) > (y) ? (x) : (y))
558 
559 #define min3(a, b, c)	min(a, min(b,c))
560 #define max3(a, b, c)	max(a, max(b,c))
561 
562 #define	min_t(type, x, y) ({			\
563 	type __min1 = (x);			\
564 	type __min2 = (y);			\
565 	__min1 < __min2 ? __min1 : __min2; })
566 
567 #define	max_t(type, x, y) ({			\
568 	type __max1 = (x);			\
569 	type __max2 = (y);			\
570 	__max1 > __max2 ? __max1 : __max2; })
571 
572 #define offsetofend(t, m)	\
573         (offsetof(t, m) + sizeof((((t *)0)->m)))
574 
575 #define	typeof_member(s, e)	typeof(((s *)0)->e)
576 
577 #define clamp_t(type, _x, min, max)	min_t(type, max_t(type, _x, min), max)
578 #define clamp(x, lo, hi)		min( max(x,lo), hi)
579 #define	clamp_val(val, lo, hi) clamp_t(typeof(val), val, lo, hi)
580 
581 /*
582  * This looks more complex than it should be. But we need to
583  * get the type for the ~ right in round_down (it needs to be
584  * as wide as the result!), and we want to evaluate the macro
585  * arguments just once each.
586  */
587 #define __round_mask(x, y) ((__typeof__(x))((y)-1))
588 #define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1)
589 #define round_down(x, y) ((x) & ~__round_mask(x, y))
590 
591 #define	smp_processor_id()	PCPU_GET(cpuid)
592 #define	num_possible_cpus()	mp_ncpus
593 #define	num_online_cpus()	mp_ncpus
594 
595 #if defined(__i386__) || defined(__amd64__)
596 extern bool linux_cpu_has_clflush;
597 #define	cpu_has_clflush		linux_cpu_has_clflush
598 #endif
599 
600 /* Swap values of a and b */
601 #define swap(a, b) do {			\
602 	typeof(a) _swap_tmp = a;	\
603 	a = b;				\
604 	b = _swap_tmp;			\
605 } while (0)
606 
607 #define	DIV_ROUND_CLOSEST(x, divisor)	(((x) + ((divisor) / 2)) / (divisor))
608 
609 #define	DIV_ROUND_CLOSEST_ULL(x, divisor) ({		\
610 	__typeof(divisor) __d = (divisor);		\
611 	unsigned long long __ret = (x) + (__d) / 2;	\
612 	__ret /= __d;					\
613 	__ret;						\
614 })
615 
616 static inline uintmax_t
617 mult_frac(uintmax_t x, uintmax_t multiplier, uintmax_t divisor)
618 {
619 	uintmax_t q = (x / divisor);
620 	uintmax_t r = (x % divisor);
621 
622 	return ((q * multiplier) + ((r * multiplier) / divisor));
623 }
624 
625 typedef struct linux_ratelimit {
626 	struct timeval lasttime;
627 	int counter;
628 } linux_ratelimit_t;
629 
630 static inline bool
631 linux_ratelimited(linux_ratelimit_t *rl)
632 {
633 	return (ppsratecheck(&rl->lasttime, &rl->counter, 1));
634 }
635 
636 #define	struct_size(ptr, field, num) ({ \
637 	const size_t __size = offsetof(__typeof(*(ptr)), field); \
638 	const size_t __max = (SIZE_MAX - __size) / sizeof((ptr)->field[0]); \
639 	((num) > __max) ? SIZE_MAX : (__size + sizeof((ptr)->field[0]) * (num)); \
640 })
641 
642 #define	__is_constexpr(x) \
643 	__builtin_constant_p(x)
644 
645 /*
646  * The is_signed() macro below returns true if the passed data type is
647  * signed. Else false is returned.
648  */
649 #define	is_signed(datatype) (((datatype)-1 / (datatype)2) == (datatype)0)
650 
651 /*
652  * The type_max() macro below returns the maxium positive value the
653  * passed data type can hold.
654  */
655 #define	type_max(datatype) ( \
656   (sizeof(datatype) >= 8) ? (is_signed(datatype) ? INT64_MAX : UINT64_MAX) : \
657   (sizeof(datatype) >= 4) ? (is_signed(datatype) ? INT32_MAX : UINT32_MAX) : \
658   (sizeof(datatype) >= 2) ? (is_signed(datatype) ? INT16_MAX : UINT16_MAX) : \
659 			    (is_signed(datatype) ? INT8_MAX : UINT8_MAX) \
660 )
661 
662 /*
663  * The type_min() macro below returns the minimum value the passed
664  * data type can hold. For unsigned types the minimum value is always
665  * zero. For signed types it may vary.
666  */
667 #define	type_min(datatype) ( \
668   (sizeof(datatype) >= 8) ? (is_signed(datatype) ? INT64_MIN : 0) : \
669   (sizeof(datatype) >= 4) ? (is_signed(datatype) ? INT32_MIN : 0) : \
670   (sizeof(datatype) >= 2) ? (is_signed(datatype) ? INT16_MIN : 0) : \
671 			    (is_signed(datatype) ? INT8_MIN : 0) \
672 )
673 
674 #define	TAINT_WARN	0
675 #define	test_taint(x)	(0)
676 #define	add_taint(x,y)	do {	\
677 	} while (0)
678 
679 static inline int
680 _h2b(const char c)
681 {
682 
683 	if (c >= '0' && c <= '9')
684 		return (c - '0');
685 	if (c >= 'a' && c <= 'f')
686 		return (10 + c - 'a');
687 	if (c >= 'A' && c <= 'F')
688 		return (10 + c - 'A');
689 	return (-EINVAL);
690 }
691 
692 static inline int
693 hex2bin(uint8_t *bindst, const char *hexsrc, size_t binlen)
694 {
695 	int hi4, lo4;
696 
697 	while (binlen > 0) {
698 		hi4 = _h2b(*hexsrc++);
699 		lo4 = _h2b(*hexsrc++);
700 		if (hi4 < 0 || lo4 < 0)
701 			return (-EINVAL);
702 
703 		*bindst++ = (hi4 << 4) | lo4;
704 		binlen--;
705 	}
706 
707 	return (0);
708 }
709 
710 static inline bool
711 mac_pton(const char *macin, uint8_t *macout)
712 {
713 	const char *s, *d;
714 	uint8_t mac[6], hx, lx;;
715 	int i;
716 
717 	if (strlen(macin) < (3 * 6 - 1))
718 		return (false);
719 
720 	i = 0;
721 	s = macin;
722 	do {
723 		/* Should we also support '-'-delimiters? */
724 		d = strchrnul(s, ':');
725 		hx = lx = 0;
726 		while (s < d) {
727 			/* Fail on abc:123:xxx:... */
728 			if ((d - s) > 2)
729 				return (false);
730 			/* We do support non-well-formed strings: 3:45:6:... */
731 			if ((d - s) > 1) {
732 				hx = _h2b(*s);
733 				if (hx < 0)
734 					return (false);
735 				s++;
736 			}
737 			lx = _h2b(*s);
738 			if (lx < 0)
739 				return (false);
740 			s++;
741 		}
742 		mac[i] = (hx << 4) | lx;
743 		i++;
744 		if (i >= 6)
745 			return (false);
746 	} while (d != NULL && *d != '\0');
747 
748 	memcpy(macout, mac, 6);
749 	return (true);
750 }
751 
752 #define	DECLARE_FLEX_ARRAY(_t, _n)					\
753     struct { struct { } __dummy_ ## _n; _t _n[0]; }
754 
755 #endif	/* _LINUXKPI_LINUX_KERNEL_H_ */
756