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 * $FreeBSD$ 31 */ 32 #ifndef _LINUXKPI_LINUX_KERNEL_H_ 33 #define _LINUXKPI_LINUX_KERNEL_H_ 34 35 #include <sys/cdefs.h> 36 #include <sys/types.h> 37 #include <sys/systm.h> 38 #include <sys/param.h> 39 #include <sys/libkern.h> 40 #include <sys/stat.h> 41 #include <sys/smp.h> 42 #include <sys/stddef.h> 43 #include <sys/syslog.h> 44 #include <sys/time.h> 45 46 #include <linux/bitops.h> 47 #include <linux/compiler.h> 48 #include <linux/stringify.h> 49 #include <linux/errno.h> 50 #include <linux/sched.h> 51 #include <linux/types.h> 52 #include <linux/jiffies.h> 53 #include <linux/log2.h> 54 55 #include <asm/byteorder.h> 56 #include <asm/uaccess.h> 57 58 #include <machine/stdarg.h> 59 60 #define KERN_CONT "" 61 #define KERN_EMERG "<0>" 62 #define KERN_ALERT "<1>" 63 #define KERN_CRIT "<2>" 64 #define KERN_ERR "<3>" 65 #define KERN_WARNING "<4>" 66 #define KERN_NOTICE "<5>" 67 #define KERN_INFO "<6>" 68 #define KERN_DEBUG "<7>" 69 70 #define U8_MAX ((u8)~0U) 71 #define S8_MAX ((s8)(U8_MAX >> 1)) 72 #define S8_MIN ((s8)(-S8_MAX - 1)) 73 #define U16_MAX ((u16)~0U) 74 #define S16_MAX ((s16)(U16_MAX >> 1)) 75 #define S16_MIN ((s16)(-S16_MAX - 1)) 76 #define U32_MAX ((u32)~0U) 77 #define S32_MAX ((s32)(U32_MAX >> 1)) 78 #define S32_MIN ((s32)(-S32_MAX - 1)) 79 #define U64_MAX ((u64)~0ULL) 80 #define S64_MAX ((s64)(U64_MAX >> 1)) 81 #define S64_MIN ((s64)(-S64_MAX - 1)) 82 83 #define S8_C(x) x 84 #define U8_C(x) x ## U 85 #define S16_C(x) x 86 #define U16_C(x) x ## U 87 #define S32_C(x) x 88 #define U32_C(x) x ## U 89 #define S64_C(x) x ## LL 90 #define U64_C(x) x ## ULL 91 92 /* 93 * BUILD_BUG_ON() can happen inside functions where _Static_assert() does not 94 * seem to work. Use old-schoold-ish CTASSERT from before commit 95 * a3085588a88fa58eb5b1eaae471999e1995a29cf but also make sure we do not 96 * end up with an unused typedef or variable. The compiler should optimise 97 * it away entirely. 98 */ 99 #define _O_CTASSERT(x) _O__CTASSERT(x, __LINE__) 100 #define _O__CTASSERT(x, y) _O___CTASSERT(x, y) 101 #define _O___CTASSERT(x, y) while (0) { \ 102 typedef char __assert_line_ ## y[(x) ? 1 : -1]; \ 103 __assert_line_ ## y _x; \ 104 _x[0] = '\0'; \ 105 } 106 107 #define BUILD_BUG() do { CTASSERT(0); } while (0) 108 #define BUILD_BUG_ON(x) do { _O_CTASSERT(!(x)) } while (0) 109 #define BUILD_BUG_ON_MSG(x, msg) BUILD_BUG_ON(x) 110 #define BUILD_BUG_ON_NOT_POWER_OF_2(x) BUILD_BUG_ON(!powerof2(x)) 111 #define BUILD_BUG_ON_INVALID(expr) while (0) { (void)(expr); } 112 113 extern const volatile int lkpi_build_bug_on_zero; 114 #define BUILD_BUG_ON_ZERO(x) ((x) ? lkpi_build_bug_on_zero : 0) 115 116 #define BUG() panic("BUG at %s:%d", __FILE__, __LINE__) 117 #define BUG_ON(cond) do { \ 118 if (cond) { \ 119 panic("BUG ON %s failed at %s:%d", \ 120 __stringify(cond), __FILE__, __LINE__); \ 121 } \ 122 } while (0) 123 124 extern int linuxkpi_warn_dump_stack; 125 #define WARN_ON(cond) ({ \ 126 bool __ret = (cond); \ 127 if (__ret) { \ 128 printf("WARNING %s failed at %s:%d\n", \ 129 __stringify(cond), __FILE__, __LINE__); \ 130 if (linuxkpi_warn_dump_stack) \ 131 linux_dump_stack(); \ 132 } \ 133 unlikely(__ret); \ 134 }) 135 136 #define WARN_ON_SMP(cond) WARN_ON(cond) 137 138 #define WARN_ON_ONCE(cond) ({ \ 139 static bool __warn_on_once; \ 140 bool __ret = (cond); \ 141 if (__ret && !__warn_on_once) { \ 142 __warn_on_once = 1; \ 143 printf("WARNING %s failed at %s:%d\n", \ 144 __stringify(cond), __FILE__, __LINE__); \ 145 if (linuxkpi_warn_dump_stack) \ 146 linux_dump_stack(); \ 147 } \ 148 unlikely(__ret); \ 149 }) 150 151 #define oops_in_progress SCHEDULER_STOPPED() 152 153 #undef ALIGN 154 #define ALIGN(x, y) roundup2((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 char *end; 439 unsigned long temp; 440 441 *res = temp = strtoul(cp, &end, base); 442 443 /* skip newline character, if any */ 444 if (*end == '\n') 445 end++; 446 if (*cp == 0 || *end != 0) 447 return (-EINVAL); 448 if (temp != (u32)temp) 449 return (-ERANGE); 450 return (0); 451 } 452 453 static inline int 454 kstrtou64(const char *cp, unsigned int base, u64 *res) 455 { 456 char *end; 457 458 *res = strtouq(cp, &end, base); 459 460 /* skip newline character, if any */ 461 if (*end == '\n') 462 end++; 463 if (*cp == 0 || *end != 0) 464 return (-EINVAL); 465 return (0); 466 } 467 468 static inline int 469 kstrtoull(const char *cp, unsigned int base, unsigned long long *res) 470 { 471 return (kstrtou64(cp, base, (u64 *)res)); 472 } 473 474 static inline int 475 kstrtobool(const char *s, bool *res) 476 { 477 int len; 478 479 if (s == NULL || (len = strlen(s)) == 0 || res == NULL) 480 return (-EINVAL); 481 482 /* skip newline character, if any */ 483 if (s[len - 1] == '\n') 484 len--; 485 486 if (len == 1 && strchr("yY1", s[0]) != NULL) 487 *res = true; 488 else if (len == 1 && strchr("nN0", s[0]) != NULL) 489 *res = false; 490 else if (strncasecmp("on", s, len) == 0) 491 *res = true; 492 else if (strncasecmp("off", s, len) == 0) 493 *res = false; 494 else 495 return (-EINVAL); 496 497 return (0); 498 } 499 500 static inline int 501 kstrtobool_from_user(const char __user *s, size_t count, bool *res) 502 { 503 char buf[8] = {}; 504 505 if (count > (sizeof(buf) - 1)) 506 count = (sizeof(buf) - 1); 507 508 if (copy_from_user(buf, s, count)) 509 return (-EFAULT); 510 511 return (kstrtobool(buf, res)); 512 } 513 514 static inline int 515 kstrtou8_from_user(const char __user *s, size_t count, unsigned int base, 516 u8 *p) 517 { 518 char buf[8] = {}; 519 520 if (count > (sizeof(buf) - 1)) 521 count = (sizeof(buf) - 1); 522 523 if (copy_from_user(buf, s, count)) 524 return (-EFAULT); 525 526 return (kstrtou8(buf, base, p)); 527 } 528 529 #define min(x, y) ((x) < (y) ? (x) : (y)) 530 #define max(x, y) ((x) > (y) ? (x) : (y)) 531 532 #define min3(a, b, c) min(a, min(b,c)) 533 #define max3(a, b, c) max(a, max(b,c)) 534 535 #define min_t(type, x, y) ({ \ 536 type __min1 = (x); \ 537 type __min2 = (y); \ 538 __min1 < __min2 ? __min1 : __min2; }) 539 540 #define max_t(type, x, y) ({ \ 541 type __max1 = (x); \ 542 type __max2 = (y); \ 543 __max1 > __max2 ? __max1 : __max2; }) 544 545 #define offsetofend(t, m) \ 546 (offsetof(t, m) + sizeof((((t *)0)->m))) 547 548 #define clamp_t(type, _x, min, max) min_t(type, max_t(type, _x, min), max) 549 #define clamp(x, lo, hi) min( max(x,lo), hi) 550 #define clamp_val(val, lo, hi) clamp_t(typeof(val), val, lo, hi) 551 552 /* 553 * This looks more complex than it should be. But we need to 554 * get the type for the ~ right in round_down (it needs to be 555 * as wide as the result!), and we want to evaluate the macro 556 * arguments just once each. 557 */ 558 #define __round_mask(x, y) ((__typeof__(x))((y)-1)) 559 #define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1) 560 #define round_down(x, y) ((x) & ~__round_mask(x, y)) 561 562 #define smp_processor_id() PCPU_GET(cpuid) 563 #define num_possible_cpus() mp_ncpus 564 #define num_online_cpus() mp_ncpus 565 566 #if defined(__i386__) || defined(__amd64__) 567 extern bool linux_cpu_has_clflush; 568 #define cpu_has_clflush linux_cpu_has_clflush 569 #endif 570 571 typedef struct pm_message { 572 int event; 573 } pm_message_t; 574 575 /* Swap values of a and b */ 576 #define swap(a, b) do { \ 577 typeof(a) _swap_tmp = a; \ 578 a = b; \ 579 b = _swap_tmp; \ 580 } while (0) 581 582 #define DIV_ROUND_CLOSEST(x, divisor) (((x) + ((divisor) / 2)) / (divisor)) 583 584 #define DIV_ROUND_CLOSEST_ULL(x, divisor) ({ \ 585 __typeof(divisor) __d = (divisor); \ 586 unsigned long long __ret = (x) + (__d) / 2; \ 587 __ret /= __d; \ 588 __ret; \ 589 }) 590 591 static inline uintmax_t 592 mult_frac(uintmax_t x, uintmax_t multiplier, uintmax_t divisor) 593 { 594 uintmax_t q = (x / divisor); 595 uintmax_t r = (x % divisor); 596 597 return ((q * multiplier) + ((r * multiplier) / divisor)); 598 } 599 600 static inline int64_t 601 abs64(int64_t x) 602 { 603 return (x < 0 ? -x : x); 604 } 605 606 typedef struct linux_ratelimit { 607 struct timeval lasttime; 608 int counter; 609 } linux_ratelimit_t; 610 611 static inline bool 612 linux_ratelimited(linux_ratelimit_t *rl) 613 { 614 return (ppsratecheck(&rl->lasttime, &rl->counter, 1)); 615 } 616 617 #define struct_size(ptr, field, num) ({ \ 618 const size_t __size = offsetof(__typeof(*(ptr)), field); \ 619 const size_t __max = (SIZE_MAX - __size) / sizeof((ptr)->field[0]); \ 620 ((num) > __max) ? SIZE_MAX : (__size + sizeof((ptr)->field[0]) * (num)); \ 621 }) 622 623 #define __is_constexpr(x) \ 624 __builtin_constant_p(x) 625 626 /* 627 * The is_signed() macro below returns true if the passed data type is 628 * signed. Else false is returned. 629 */ 630 #define is_signed(datatype) (((datatype)-1 / (datatype)2) == (datatype)0) 631 632 /* 633 * The type_max() macro below returns the maxium positive value the 634 * passed data type can hold. 635 */ 636 #define type_max(datatype) ( \ 637 (sizeof(datatype) >= 8) ? (is_signed(datatype) ? INT64_MAX : UINT64_MAX) : \ 638 (sizeof(datatype) >= 4) ? (is_signed(datatype) ? INT32_MAX : UINT32_MAX) : \ 639 (sizeof(datatype) >= 2) ? (is_signed(datatype) ? INT16_MAX : UINT16_MAX) : \ 640 (is_signed(datatype) ? INT8_MAX : UINT8_MAX) \ 641 ) 642 643 /* 644 * The type_min() macro below returns the minimum value the passed 645 * data type can hold. For unsigned types the minimum value is always 646 * zero. For signed types it may vary. 647 */ 648 #define type_min(datatype) ( \ 649 (sizeof(datatype) >= 8) ? (is_signed(datatype) ? INT64_MIN : 0) : \ 650 (sizeof(datatype) >= 4) ? (is_signed(datatype) ? INT32_MIN : 0) : \ 651 (sizeof(datatype) >= 2) ? (is_signed(datatype) ? INT16_MIN : 0) : \ 652 (is_signed(datatype) ? INT8_MIN : 0) \ 653 ) 654 655 #define TAINT_WARN 0 656 #define test_taint(x) (0) 657 658 static inline int 659 _h2b(const char c) 660 { 661 662 if (c >= '0' && c <= '9') 663 return (c - '0'); 664 if (c >= 'a' && c <= 'f') 665 return (10 + c - 'a'); 666 if (c >= 'A' && c <= 'F') 667 return (10 + c - 'A'); 668 return (-EINVAL); 669 } 670 671 static inline int 672 hex2bin(uint8_t *bindst, const char *hexsrc, size_t binlen) 673 { 674 int hi4, lo4; 675 676 while (binlen > 0) { 677 hi4 = _h2b(*hexsrc++); 678 lo4 = _h2b(*hexsrc++); 679 if (hi4 < 0 || lo4 < 0) 680 return (-EINVAL); 681 682 *bindst++ = (hi4 << 4) | lo4; 683 binlen--; 684 } 685 686 return (0); 687 } 688 689 /* 690 * Checking if an option is defined would be easy if we could do CPP inside CPP. 691 * The defined case whether -Dxxx or -Dxxx=1 are easy to deal with. In either 692 * case the defined value is "1". A more general -Dxxx=<c> case will require 693 * more effort to deal with all possible "true" values. Hope we do not have 694 * to do this as well. 695 * The real problem is the undefined case. To avoid this problem we do the 696 * concat/varargs trick: "yyy" ## xxx can make two arguments if xxx is "1" 697 * by having a #define for yyy_1 which is "ignore,". 698 * Otherwise we will just get "yyy". 699 * Need to be careful about variable substitutions in macros though. 700 * This way we make a (true, false) problem a (don't care, true, false) or a 701 * (don't care true, false). Then we can use a variadic macro to only select 702 * the always well known and defined argument #2. And that seems to be 703 * exactly what we need. Use 1 for true and 0 for false to also allow 704 * #if IS_*() checks pre-compiler checks which do not like #if true. 705 */ 706 #define ___XAB_1 dontcare, 707 #define ___IS_XAB(_ignore, _x, ...) (_x) 708 #define __IS_XAB(_x) ___IS_XAB(_x 1, 0) 709 #define _IS_XAB(_x) __IS_XAB(__CONCAT(___XAB_, _x)) 710 711 /* This is if CONFIG_ccc=y. */ 712 #define IS_BUILTIN(_x) _IS_XAB(_x) 713 /* This is if CONFIG_ccc=m. */ 714 #define IS_MODULE(_x) _IS_XAB(_x ## _MODULE) 715 /* This is if CONFIG_ccc is compiled in(=y) or a module(=m). */ 716 #define IS_ENABLED(_x) (IS_BUILTIN(_x) || IS_MODULE(_x)) 717 /* 718 * This is weird case. If the CONFIG_ccc is builtin (=y) this returns true; 719 * or if the CONFIG_ccc is a module (=m) and the caller is built as a module 720 * (-DMODULE defined) this returns true, but if the callers is not a module 721 * (-DMODULE not defined, which means caller is BUILTIN) then it returns 722 * false. In other words, a module can reach the kernel, a module can reach 723 * a module, but the kernel cannot reach a module, and code never compiled 724 * cannot be reached either. 725 * XXX -- I'd hope the module-to-module case would be handled by a proper 726 * module dependency definition (MODULE_DEPEND() in FreeBSD). 727 */ 728 #define IS_REACHABLE(_x) (IS_BUILTIN(_x) || \ 729 (IS_MODULE(_x) && IS_BUILTIN(MODULE))) 730 731 #endif /* _LINUXKPI_LINUX_KERNEL_H_ */ 732