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/build_bug.h>
45 #include <linux/compiler.h>
46 #include <linux/container_of.h>
47 #include <linux/limits.h>
48 #include <linux/stringify.h>
49 #include <linux/errno.h>
50 #include <linux/sched.h>
51 #include <linux/types.h>
52 #include <linux/typecheck.h>
53 #include <linux/jiffies.h>
54 #include <linux/log2.h>
55 #include <linux/kconfig.h>
56
57 #include <asm/byteorder.h>
58 #include <asm/cpufeature.h>
59 #include <asm/processor.h>
60 #include <asm/uaccess.h>
61
62 #include <linux/stdarg.h>
63
64 #define KERN_CONT ""
65 #define KERN_EMERG "<0>"
66 #define KERN_ALERT "<1>"
67 #define KERN_CRIT "<2>"
68 #define KERN_ERR "<3>"
69 #define KERN_WARNING "<4>"
70 #define KERN_NOTICE "<5>"
71 #define KERN_INFO "<6>"
72 #define KERN_DEBUG "<7>"
73
74 #define S8_C(x) x
75 #define U8_C(x) x ## U
76 #define S16_C(x) x
77 #define U16_C(x) x ## U
78 #define S32_C(x) x
79 #define U32_C(x) x ## U
80 #define S64_C(x) x ## LL
81 #define U64_C(x) x ## ULL
82
83 #define BUG() panic("BUG at %s:%d", __FILE__, __LINE__)
84 #define BUG_ON(cond) do { \
85 if (cond) { \
86 panic("BUG ON %s failed at %s:%d", \
87 __stringify(cond), __FILE__, __LINE__); \
88 } \
89 } while (0)
90
91 extern int linuxkpi_warn_dump_stack;
92 #define WARN_ON(cond) ({ \
93 bool __ret = (cond); \
94 if (__ret) { \
95 printf("WARNING %s failed at %s:%d\n", \
96 __stringify(cond), __FILE__, __LINE__); \
97 if (linuxkpi_warn_dump_stack) \
98 linux_dump_stack(); \
99 } \
100 unlikely(__ret); \
101 })
102
103 #define WARN_ON_SMP(cond) WARN_ON(cond)
104
105 #define WARN_ON_ONCE(cond) ({ \
106 static bool __warn_on_once; \
107 bool __ret = (cond); \
108 if (__ret && !__warn_on_once) { \
109 __warn_on_once = 1; \
110 printf("WARNING %s failed at %s:%d\n", \
111 __stringify(cond), __FILE__, __LINE__); \
112 if (linuxkpi_warn_dump_stack) \
113 linux_dump_stack(); \
114 } \
115 unlikely(__ret); \
116 })
117
118 #define oops_in_progress SCHEDULER_STOPPED()
119
120 #undef ALIGN
121 #define ALIGN(x, y) roundup2((x), (y))
122 #define ALIGN_DOWN(x, y) rounddown2(x, y)
123 #undef PTR_ALIGN
124 #define PTR_ALIGN(p, a) ((__typeof(p))ALIGN((uintptr_t)(p), (a)))
125 #define IS_ALIGNED(x, a) (((x) & ((__typeof(x))(a) - 1)) == 0)
126 #define DIV_ROUND_UP(x, n) howmany(x, n)
127 #define __KERNEL_DIV_ROUND_UP(x, n) howmany(x, n)
128 #define DIV_ROUND_UP_ULL(x, n) DIV_ROUND_UP((unsigned long long)(x), (n))
129 #define DIV_ROUND_DOWN_ULL(x, n) (((unsigned long long)(x) / (n)) * (n))
130 #define FIELD_SIZEOF(t, f) sizeof(((t *)0)->f)
131
132 #define printk(...) printf(__VA_ARGS__)
133 #define vprintk(f, a) vprintf(f, a)
134
135 #define PTR_IF(x, p) ((x) ? (p) : NULL)
136
137 #define asm __asm
138
139 extern void linux_dump_stack(void);
140 #define dump_stack() linux_dump_stack()
141
142 struct va_format {
143 const char *fmt;
144 va_list *va;
145 };
146
147 static inline int
vscnprintf(char * buf,size_t size,const char * fmt,va_list args)148 vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
149 {
150 ssize_t ssize = size;
151 int i;
152
153 i = vsnprintf(buf, size, fmt, args);
154
155 return ((i >= ssize) ? (ssize - 1) : i);
156 }
157
158 static inline int
scnprintf(char * buf,size_t size,const char * fmt,...)159 scnprintf(char *buf, size_t size, const char *fmt, ...)
160 {
161 va_list args;
162 int i;
163
164 va_start(args, fmt);
165 i = vscnprintf(buf, size, fmt, args);
166 va_end(args);
167
168 return (i);
169 }
170
171 /*
172 * The "pr_debug()" and "pr_devel()" macros should produce zero code
173 * unless DEBUG is defined:
174 */
175 #ifdef DEBUG
176 extern int linuxkpi_debug;
177 #define pr_debug(fmt, ...) \
178 do { \
179 if (linuxkpi_debug) \
180 log(LOG_DEBUG, fmt, ##__VA_ARGS__); \
181 } while (0)
182 #define pr_devel(fmt, ...) \
183 log(LOG_DEBUG, pr_fmt(fmt), ##__VA_ARGS__)
184 #else
185 #define pr_debug(fmt, ...) \
186 ({ if (0) log(LOG_DEBUG, fmt, ##__VA_ARGS__); 0; })
187 #define pr_devel(fmt, ...) \
188 ({ if (0) log(LOG_DEBUG, pr_fmt(fmt), ##__VA_ARGS__); 0; })
189 #endif
190
191 #ifndef pr_fmt
192 #define pr_fmt(fmt) fmt
193 #endif
194
195 /*
196 * Print a one-time message (analogous to WARN_ONCE() et al):
197 */
198 #define printk_once(...) do { \
199 static bool __print_once; \
200 \
201 if (!__print_once) { \
202 __print_once = true; \
203 printk(__VA_ARGS__); \
204 } \
205 } while (0)
206
207 /*
208 * Log a one-time message (analogous to WARN_ONCE() et al):
209 */
210 #define log_once(level,...) do { \
211 static bool __log_once; \
212 \
213 if (unlikely(!__log_once)) { \
214 __log_once = true; \
215 log(level, __VA_ARGS__); \
216 } \
217 } while (0)
218
219 #define pr_emerg(fmt, ...) \
220 log(LOG_EMERG, pr_fmt(fmt), ##__VA_ARGS__)
221 #define pr_alert(fmt, ...) \
222 log(LOG_ALERT, pr_fmt(fmt), ##__VA_ARGS__)
223 #define pr_crit(fmt, ...) \
224 log(LOG_CRIT, pr_fmt(fmt), ##__VA_ARGS__)
225 #define pr_err(fmt, ...) \
226 log(LOG_ERR, pr_fmt(fmt), ##__VA_ARGS__)
227 #define pr_err_once(fmt, ...) \
228 log_once(LOG_ERR, pr_fmt(fmt), ##__VA_ARGS__)
229 #define pr_warning(fmt, ...) \
230 log(LOG_WARNING, pr_fmt(fmt), ##__VA_ARGS__)
231 #define pr_warn(...) \
232 pr_warning(__VA_ARGS__)
233 #define pr_warn_once(fmt, ...) \
234 log_once(LOG_WARNING, pr_fmt(fmt), ##__VA_ARGS__)
235 #define pr_notice(fmt, ...) \
236 log(LOG_NOTICE, pr_fmt(fmt), ##__VA_ARGS__)
237 #define pr_info(fmt, ...) \
238 log(LOG_INFO, pr_fmt(fmt), ##__VA_ARGS__)
239 #define pr_info_once(fmt, ...) \
240 log_once(LOG_INFO, pr_fmt(fmt), ##__VA_ARGS__)
241 #define pr_cont(fmt, ...) \
242 printk(KERN_CONT fmt, ##__VA_ARGS__)
243 #define pr_warn_ratelimited(...) do { \
244 static linux_ratelimit_t __ratelimited; \
245 if (linux_ratelimited(&__ratelimited)) \
246 pr_warning(__VA_ARGS__); \
247 } while (0)
248
249 #ifndef WARN
250 #define WARN(condition, ...) ({ \
251 bool __ret_warn_on = (condition); \
252 if (unlikely(__ret_warn_on)) \
253 pr_warning(__VA_ARGS__); \
254 unlikely(__ret_warn_on); \
255 })
256 #endif
257
258 #ifndef WARN_ONCE
259 #define WARN_ONCE(condition, ...) ({ \
260 bool __ret_warn_on = (condition); \
261 if (unlikely(__ret_warn_on)) \
262 pr_warn_once(__VA_ARGS__); \
263 unlikely(__ret_warn_on); \
264 })
265 #endif
266
267 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
268
269 #define u64_to_user_ptr(val) ((void *)(uintptr_t)(val))
270
271 #define _RET_IP_ __builtin_return_address(0)
272
273 static inline unsigned long long
simple_strtoull(const char * cp,char ** endp,unsigned int base)274 simple_strtoull(const char *cp, char **endp, unsigned int base)
275 {
276 return (strtouq(cp, endp, base));
277 }
278
279 static inline long long
simple_strtoll(const char * cp,char ** endp,unsigned int base)280 simple_strtoll(const char *cp, char **endp, unsigned int base)
281 {
282 return (strtoq(cp, endp, base));
283 }
284
285 static inline unsigned long
simple_strtoul(const char * cp,char ** endp,unsigned int base)286 simple_strtoul(const char *cp, char **endp, unsigned int base)
287 {
288 return (strtoul(cp, endp, base));
289 }
290
291 static inline long
simple_strtol(const char * cp,char ** endp,unsigned int base)292 simple_strtol(const char *cp, char **endp, unsigned int base)
293 {
294 return (strtol(cp, endp, base));
295 }
296
297 static inline int
kstrtoul(const char * cp,unsigned int base,unsigned long * res)298 kstrtoul(const char *cp, unsigned int base, unsigned long *res)
299 {
300 char *end;
301
302 *res = strtoul(cp, &end, base);
303
304 /* skip newline character, if any */
305 if (*end == '\n')
306 end++;
307 if (*cp == 0 || *end != 0)
308 return (-EINVAL);
309 return (0);
310 }
311
312 static inline int
kstrtol(const char * cp,unsigned int base,long * res)313 kstrtol(const char *cp, unsigned int base, long *res)
314 {
315 char *end;
316
317 *res = strtol(cp, &end, base);
318
319 /* skip newline character, if any */
320 if (*end == '\n')
321 end++;
322 if (*cp == 0 || *end != 0)
323 return (-EINVAL);
324 return (0);
325 }
326
327 static inline int
kstrtoint(const char * cp,unsigned int base,int * res)328 kstrtoint(const char *cp, unsigned int base, int *res)
329 {
330 char *end;
331 long temp;
332
333 *res = temp = strtol(cp, &end, base);
334
335 /* skip newline character, if any */
336 if (*end == '\n')
337 end++;
338 if (*cp == 0 || *end != 0)
339 return (-EINVAL);
340 if (temp != (int)temp)
341 return (-ERANGE);
342 return (0);
343 }
344
345 static inline int
kstrtouint(const char * cp,unsigned int base,unsigned int * res)346 kstrtouint(const char *cp, unsigned int base, unsigned int *res)
347 {
348 char *end;
349 unsigned long temp;
350
351 *res = temp = strtoul(cp, &end, base);
352
353 /* skip newline character, if any */
354 if (*end == '\n')
355 end++;
356 if (*cp == 0 || *end != 0)
357 return (-EINVAL);
358 if (temp != (unsigned int)temp)
359 return (-ERANGE);
360 return (0);
361 }
362
363 static inline int
kstrtou8(const char * cp,unsigned int base,u8 * res)364 kstrtou8(const char *cp, unsigned int base, u8 *res)
365 {
366 char *end;
367 unsigned long temp;
368
369 *res = temp = strtoul(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 != (u8)temp)
377 return (-ERANGE);
378 return (0);
379 }
380
381 static inline int
kstrtou16(const char * cp,unsigned int base,u16 * res)382 kstrtou16(const char *cp, unsigned int base, u16 *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 != (u16)temp)
395 return (-ERANGE);
396 return (0);
397 }
398
399 static inline int
kstrtou32(const char * cp,unsigned int base,u32 * res)400 kstrtou32(const char *cp, unsigned int base, u32 *res)
401 {
402
403 return (kstrtouint(cp, base, res));
404 }
405
406 static inline int
kstrtou64(const char * cp,unsigned int base,u64 * res)407 kstrtou64(const char *cp, unsigned int base, u64 *res)
408 {
409 char *end;
410
411 *res = strtouq(cp, &end, base);
412
413 /* skip newline character, if any */
414 if (*end == '\n')
415 end++;
416 if (*cp == 0 || *end != 0)
417 return (-EINVAL);
418 return (0);
419 }
420
421 static inline int
kstrtoull(const char * cp,unsigned int base,unsigned long long * res)422 kstrtoull(const char *cp, unsigned int base, unsigned long long *res)
423 {
424 return (kstrtou64(cp, base, (u64 *)res));
425 }
426
427 static inline int
kstrtobool(const char * s,bool * res)428 kstrtobool(const char *s, bool *res)
429 {
430 int len;
431
432 if (s == NULL || (len = strlen(s)) == 0 || res == NULL)
433 return (-EINVAL);
434
435 /* skip newline character, if any */
436 if (s[len - 1] == '\n')
437 len--;
438
439 if (len == 1 && strchr("yY1", s[0]) != NULL)
440 *res = true;
441 else if (len == 1 && strchr("nN0", s[0]) != NULL)
442 *res = false;
443 else if (strncasecmp("on", s, len) == 0)
444 *res = true;
445 else if (strncasecmp("off", s, len) == 0)
446 *res = false;
447 else
448 return (-EINVAL);
449
450 return (0);
451 }
452
453 static inline int
kstrtobool_from_user(const char __user * s,size_t count,bool * res)454 kstrtobool_from_user(const char __user *s, size_t count, bool *res)
455 {
456 char buf[8] = {};
457
458 if (count > (sizeof(buf) - 1))
459 count = (sizeof(buf) - 1);
460
461 if (copy_from_user(buf, s, count))
462 return (-EFAULT);
463
464 return (kstrtobool(buf, res));
465 }
466
467 static inline int
kstrtoint_from_user(const char __user * s,size_t count,unsigned int base,int * p)468 kstrtoint_from_user(const char __user *s, size_t count, unsigned int base,
469 int *p)
470 {
471 char buf[36] = {};
472
473 if (count > (sizeof(buf) - 1))
474 count = (sizeof(buf) - 1);
475
476 if (copy_from_user(buf, s, count))
477 return (-EFAULT);
478
479 return (kstrtoint(buf, base, p));
480 }
481
482 static inline int
kstrtouint_from_user(const char __user * s,size_t count,unsigned int base,unsigned int * p)483 kstrtouint_from_user(const char __user *s, size_t count, unsigned int base,
484 unsigned int *p)
485 {
486 char buf[36] = {};
487
488 if (count > (sizeof(buf) - 1))
489 count = (sizeof(buf) - 1);
490
491 if (copy_from_user(buf, s, count))
492 return (-EFAULT);
493
494 return (kstrtouint(buf, base, p));
495 }
496
497 static inline int
kstrtou32_from_user(const char __user * s,size_t count,unsigned int base,unsigned int * p)498 kstrtou32_from_user(const char __user *s, size_t count, unsigned int base,
499 unsigned int *p)
500 {
501
502 return (kstrtouint_from_user(s, count, base, p));
503 }
504
505 static inline int
kstrtou8_from_user(const char __user * s,size_t count,unsigned int base,u8 * p)506 kstrtou8_from_user(const char __user *s, size_t count, unsigned int base,
507 u8 *p)
508 {
509 char buf[8] = {};
510
511 if (count > (sizeof(buf) - 1))
512 count = (sizeof(buf) - 1);
513
514 if (copy_from_user(buf, s, count))
515 return (-EFAULT);
516
517 return (kstrtou8(buf, base, p));
518 }
519
520 #define min(x, y) ((x) < (y) ? (x) : (y))
521 #define max(x, y) ((x) > (y) ? (x) : (y))
522
523 #define min3(a, b, c) min(a, min(b,c))
524 #define max3(a, b, c) max(a, max(b,c))
525
526 #define min_t(type, x, y) ({ \
527 type __min1 = (x); \
528 type __min2 = (y); \
529 __min1 < __min2 ? __min1 : __min2; })
530
531 #define max_t(type, x, y) ({ \
532 type __max1 = (x); \
533 type __max2 = (y); \
534 __max1 > __max2 ? __max1 : __max2; })
535
536 #define offsetofend(t, m) \
537 (offsetof(t, m) + sizeof((((t *)0)->m)))
538
539 #define clamp_t(type, _x, min, max) min_t(type, max_t(type, _x, min), max)
540 #define clamp(x, lo, hi) min( max(x,lo), hi)
541 #define clamp_val(val, lo, hi) clamp_t(typeof(val), val, lo, hi)
542
543 /*
544 * This looks more complex than it should be. But we need to
545 * get the type for the ~ right in round_down (it needs to be
546 * as wide as the result!), and we want to evaluate the macro
547 * arguments just once each.
548 */
549 #define __round_mask(x, y) ((__typeof__(x))((y)-1))
550 #define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1)
551 #define round_down(x, y) ((x) & ~__round_mask(x, y))
552
553 #define smp_processor_id() PCPU_GET(cpuid)
554 #define num_possible_cpus() mp_ncpus
555 #define num_online_cpus() mp_ncpus
556
557 #if defined(__i386__) || defined(__amd64__)
558 extern bool linux_cpu_has_clflush;
559 #define cpu_has_clflush linux_cpu_has_clflush
560 #endif
561
562 /* Swap values of a and b */
563 #define swap(a, b) do { \
564 typeof(a) _swap_tmp = a; \
565 a = b; \
566 b = _swap_tmp; \
567 } while (0)
568
569 #define DIV_ROUND_CLOSEST(x, divisor) (((x) + ((divisor) / 2)) / (divisor))
570
571 #define DIV_ROUND_CLOSEST_ULL(x, divisor) ({ \
572 __typeof(divisor) __d = (divisor); \
573 unsigned long long __ret = (x) + (__d) / 2; \
574 __ret /= __d; \
575 __ret; \
576 })
577
578 static inline uintmax_t
mult_frac(uintmax_t x,uintmax_t multiplier,uintmax_t divisor)579 mult_frac(uintmax_t x, uintmax_t multiplier, uintmax_t divisor)
580 {
581 uintmax_t q = (x / divisor);
582 uintmax_t r = (x % divisor);
583
584 return ((q * multiplier) + ((r * multiplier) / divisor));
585 }
586
587 typedef struct linux_ratelimit {
588 struct timeval lasttime;
589 int counter;
590 } linux_ratelimit_t;
591
592 static inline bool
linux_ratelimited(linux_ratelimit_t * rl)593 linux_ratelimited(linux_ratelimit_t *rl)
594 {
595 return (ppsratecheck(&rl->lasttime, &rl->counter, 1));
596 }
597
598 #define __is_constexpr(x) \
599 __builtin_constant_p(x)
600
601 /*
602 * The is_signed() macro below returns true if the passed data type is
603 * signed. Else false is returned.
604 */
605 #define is_signed(datatype) (((datatype)-1 / (datatype)2) == (datatype)0)
606
607 #define TAINT_WARN 0
608 #define test_taint(x) (0)
609 #define add_taint(x,y) do { \
610 } while (0)
611
612 static inline int
_h2b(const char c)613 _h2b(const char c)
614 {
615
616 if (c >= '0' && c <= '9')
617 return (c - '0');
618 if (c >= 'a' && c <= 'f')
619 return (10 + c - 'a');
620 if (c >= 'A' && c <= 'F')
621 return (10 + c - 'A');
622 return (-EINVAL);
623 }
624
625 static inline int
hex2bin(uint8_t * bindst,const char * hexsrc,size_t binlen)626 hex2bin(uint8_t *bindst, const char *hexsrc, size_t binlen)
627 {
628 int hi4, lo4;
629
630 while (binlen > 0) {
631 hi4 = _h2b(*hexsrc++);
632 lo4 = _h2b(*hexsrc++);
633 if (hi4 < 0 || lo4 < 0)
634 return (-EINVAL);
635
636 *bindst++ = (hi4 << 4) | lo4;
637 binlen--;
638 }
639
640 return (0);
641 }
642
643 static inline bool
mac_pton(const char * macin,uint8_t * macout)644 mac_pton(const char *macin, uint8_t *macout)
645 {
646 const char *s, *d;
647 uint8_t mac[6], hx, lx;;
648 int i;
649
650 if (strlen(macin) < (3 * 6 - 1))
651 return (false);
652
653 i = 0;
654 s = macin;
655 do {
656 /* Should we also support '-'-delimiters? */
657 d = strchrnul(s, ':');
658 hx = lx = 0;
659 while (s < d) {
660 /* Fail on abc:123:xxx:... */
661 if ((d - s) > 2)
662 return (false);
663 /* We do support non-well-formed strings: 3:45:6:... */
664 if ((d - s) > 1) {
665 hx = _h2b(*s);
666 if (hx < 0)
667 return (false);
668 s++;
669 }
670 lx = _h2b(*s);
671 if (lx < 0)
672 return (false);
673 s++;
674 }
675 mac[i] = (hx << 4) | lx;
676 i++;
677 if (i >= 6)
678 return (false);
679 } while (d != NULL && *d != '\0');
680
681 memcpy(macout, mac, 6);
682 return (true);
683 }
684
685 #define DECLARE_FLEX_ARRAY(_t, _n) \
686 struct { struct { } __dummy_ ## _n; _t _n[0]; }
687
688 #endif /* _LINUXKPI_LINUX_KERNEL_H_ */
689