projects/linux·blob v4.6-rc5 · refs

2898 lines · 66.8 KiB

1/*
2 * linux/lib/vsprintf.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 */
6
7/* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */
8/*
9 * Wirzenius wrote this portably, Torvalds fucked it up :-)
10 */
11
12/*
13 * Fri Jul 13 2001 Crutcher Dunnavant <[email protected]>
14 * - changed to provide snprintf and vsnprintf functions
15 * So Feb 1 16:51:32 CET 2004 Juergen Quade <[email protected]>
16 * - scnprintf and vscnprintf
17 */
18
19#include <stdarg.h>
20#include <linux/clk.h>
21#include <linux/clk-provider.h>
22#include <linux/module.h> /* for KSYM_SYMBOL_LEN */
23#include <linux/types.h>
24#include <linux/string.h>
25#include <linux/ctype.h>
26#include <linux/kernel.h>
27#include <linux/kallsyms.h>
28#include <linux/math64.h>
29#include <linux/uaccess.h>
30#include <linux/ioport.h>
31#include <linux/dcache.h>
32#include <linux/cred.h>
33#include <net/addrconf.h>
34#ifdef CONFIG_BLOCK
35#include <linux/blkdev.h>
36#endif
37
38#include "../mm/internal.h" /* For the trace_print_flags arrays */
39
40#include <asm/page.h> /* for PAGE_SIZE */
41#include <asm/sections.h> /* for dereference_function_descriptor() */
42#include <asm/byteorder.h> /* cpu_to_le16 */
43
44#include <linux/string_helpers.h>
45#include "kstrtox.h"
46
47/**
48 * simple_strtoull - convert a string to an unsigned long long
49 * @cp: The start of the string
50 * @endp: A pointer to the end of the parsed string will be placed here
51 * @base: The number base to use
52 *
53 * This function is obsolete. Please use kstrtoull instead.
54 */
55unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
56{
57 unsigned long long result;
58 unsigned int rv;
59
60 cp = _parse_integer_fixup_radix(cp, &base);
61 rv = _parse_integer(cp, base, &result);
62 /* FIXME */
63 cp += (rv & ~KSTRTOX_OVERFLOW);
64
65 if (endp)
66 *endp = (char *)cp;
67
68 return result;
69}
70EXPORT_SYMBOL(simple_strtoull);
71
72/**
73 * simple_strtoul - convert a string to an unsigned long
74 * @cp: The start of the string
75 * @endp: A pointer to the end of the parsed string will be placed here
76 * @base: The number base to use
77 *
78 * This function is obsolete. Please use kstrtoul instead.
79 */
80unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
81{
82 return simple_strtoull(cp, endp, base);
83}
84EXPORT_SYMBOL(simple_strtoul);
85
86/**
87 * simple_strtol - convert a string to a signed long
88 * @cp: The start of the string
89 * @endp: A pointer to the end of the parsed string will be placed here
90 * @base: The number base to use
91 *
92 * This function is obsolete. Please use kstrtol instead.
93 */
94long simple_strtol(const char *cp, char **endp, unsigned int base)
95{
96 if (*cp == '-')
97 return -simple_strtoul(cp + 1, endp, base);
98
99 return simple_strtoul(cp, endp, base);
100}
101EXPORT_SYMBOL(simple_strtol);
102
103/**
104 * simple_strtoll - convert a string to a signed long long
105 * @cp: The start of the string
106 * @endp: A pointer to the end of the parsed string will be placed here
107 * @base: The number base to use
108 *
109 * This function is obsolete. Please use kstrtoll instead.
110 */
111long long simple_strtoll(const char *cp, char **endp, unsigned int base)
112{
113 if (*cp == '-')
114 return -simple_strtoull(cp + 1, endp, base);
115
116 return simple_strtoull(cp, endp, base);
117}
118EXPORT_SYMBOL(simple_strtoll);
119
120static noinline_for_stack
121int skip_atoi(const char **s)
122{
123 int i = 0;
124
125 do {
126 i = i*10 + *((*s)++) - '0';
127 } while (isdigit(**s));
128
129 return i;
130}
131
132/*
133 * Decimal conversion is by far the most typical, and is used for
134 * /proc and /sys data. This directly impacts e.g. top performance
135 * with many processes running. We optimize it for speed by emitting
136 * two characters at a time, using a 200 byte lookup table. This
137 * roughly halves the number of multiplications compared to computing
138 * the digits one at a time. Implementation strongly inspired by the
139 * previous version, which in turn used ideas described at
140 * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission
141 * from the author, Douglas W. Jones).
142 *
143 * It turns out there is precisely one 26 bit fixed-point
144 * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32
145 * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual
146 * range happens to be somewhat larger (x <= 1073741898), but that's
147 * irrelevant for our purpose.
148 *
149 * For dividing a number in the range [10^4, 10^6-1] by 100, we still
150 * need a 32x32->64 bit multiply, so we simply use the same constant.
151 *
152 * For dividing a number in the range [100, 10^4-1] by 100, there are
153 * several options. The simplest is (x * 0x147b) >> 19, which is valid
154 * for all x <= 43698.
155 */
156
157static const u16 decpair[100] = {
158#define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030)
159 _( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9),
160 _(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19),
161 _(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29),
162 _(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39),
163 _(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49),
164 _(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59),
165 _(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69),
166 _(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79),
167 _(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89),
168 _(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99),
169#undef _
170};
171
172/*
173 * This will print a single '0' even if r == 0, since we would
174 * immediately jump to out_r where two 0s would be written but only
175 * one of them accounted for in buf. This is needed by ip4_string
176 * below. All other callers pass a non-zero value of r.
177*/
178static noinline_for_stack
179char *put_dec_trunc8(char *buf, unsigned r)
180{
181 unsigned q;
182
183 /* 1 <= r < 10^8 */
184 if (r < 100)
185 goto out_r;
186
187 /* 100 <= r < 10^8 */
188 q = (r * (u64)0x28f5c29) >> 32;
189 *((u16 *)buf) = decpair[r - 100*q];
190 buf += 2;
191
192 /* 1 <= q < 10^6 */
193 if (q < 100)
194 goto out_q;
195
196 /* 100 <= q < 10^6 */
197 r = (q * (u64)0x28f5c29) >> 32;
198 *((u16 *)buf) = decpair[q - 100*r];
199 buf += 2;
200
201 /* 1 <= r < 10^4 */
202 if (r < 100)
203 goto out_r;
204
205 /* 100 <= r < 10^4 */
206 q = (r * 0x147b) >> 19;
207 *((u16 *)buf) = decpair[r - 100*q];
208 buf += 2;
209out_q:
210 /* 1 <= q < 100 */
211 r = q;
212out_r:
213 /* 1 <= r < 100 */
214 *((u16 *)buf) = decpair[r];
215 buf += r < 10 ? 1 : 2;
216 return buf;
217}
218
219#if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64
220static noinline_for_stack
221char *put_dec_full8(char *buf, unsigned r)
222{
223 unsigned q;
224
225 /* 0 <= r < 10^8 */
226 q = (r * (u64)0x28f5c29) >> 32;
227 *((u16 *)buf) = decpair[r - 100*q];
228 buf += 2;
229
230 /* 0 <= q < 10^6 */
231 r = (q * (u64)0x28f5c29) >> 32;
232 *((u16 *)buf) = decpair[q - 100*r];
233 buf += 2;
234
235 /* 0 <= r < 10^4 */
236 q = (r * 0x147b) >> 19;
237 *((u16 *)buf) = decpair[r - 100*q];
238 buf += 2;
239
240 /* 0 <= q < 100 */
241 *((u16 *)buf) = decpair[q];
242 buf += 2;
243 return buf;
244}
245
246static noinline_for_stack
247char *put_dec(char *buf, unsigned long long n)
248{
249 if (n >= 100*1000*1000)
250 buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
251 /* 1 <= n <= 1.6e11 */
252 if (n >= 100*1000*1000)
253 buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
254 /* 1 <= n < 1e8 */
255 return put_dec_trunc8(buf, n);
256}
257
258#elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64
259
260static void
261put_dec_full4(char *buf, unsigned r)
262{
263 unsigned q;
264
265 /* 0 <= r < 10^4 */
266 q = (r * 0x147b) >> 19;
267 *((u16 *)buf) = decpair[r - 100*q];
268 buf += 2;
269 /* 0 <= q < 100 */
270 *((u16 *)buf) = decpair[q];
271}
272
273/*
274 * Call put_dec_full4 on x % 10000, return x / 10000.
275 * The approximation x/10000 == (x * 0x346DC5D7) >> 43
276 * holds for all x < 1,128,869,999. The largest value this
277 * helper will ever be asked to convert is 1,125,520,955.
278 * (second call in the put_dec code, assuming n is all-ones).
279 */
280static noinline_for_stack
281unsigned put_dec_helper4(char *buf, unsigned x)
282{
283 uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43;
284
285 put_dec_full4(buf, x - q * 10000);
286 return q;
287}
288
289/* Based on code by Douglas W. Jones found at
290 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour>
291 * (with permission from the author).
292 * Performs no 64-bit division and hence should be fast on 32-bit machines.
293 */
294static
295char *put_dec(char *buf, unsigned long long n)
296{
297 uint32_t d3, d2, d1, q, h;
298
299 if (n < 100*1000*1000)
300 return put_dec_trunc8(buf, n);
301
302 d1 = ((uint32_t)n >> 16); /* implicit "& 0xffff" */
303 h = (n >> 32);
304 d2 = (h ) & 0xffff;
305 d3 = (h >> 16); /* implicit "& 0xffff" */
306
307 /* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0
308 = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */
309 q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff);
310 q = put_dec_helper4(buf, q);
311
312 q += 7671 * d3 + 9496 * d2 + 6 * d1;
313 q = put_dec_helper4(buf+4, q);
314
315 q += 4749 * d3 + 42 * d2;
316 q = put_dec_helper4(buf+8, q);
317
318 q += 281 * d3;
319 buf += 12;
320 if (q)
321 buf = put_dec_trunc8(buf, q);
322 else while (buf[-1] == '0')
323 --buf;
324
325 return buf;
326}
327
328#endif
329
330/*
331 * Convert passed number to decimal string.
332 * Returns the length of string. On buffer overflow, returns 0.
333 *
334 * If speed is not important, use snprintf(). It's easy to read the code.
335 */
336int num_to_str(char *buf, int size, unsigned long long num)
337{
338 /* put_dec requires 2-byte alignment of the buffer. */
339 char tmp[sizeof(num) * 3] __aligned(2);
340 int idx, len;
341
342 /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */
343 if (num <= 9) {
344 tmp[0] = '0' + num;
345 len = 1;
346 } else {
347 len = put_dec(tmp, num) - tmp;
348 }
349
350 if (len > size)
351 return 0;
352 for (idx = 0; idx < len; ++idx)
353 buf[idx] = tmp[len - idx - 1];
354 return len;
355}
356
357#define SIGN 1 /* unsigned/signed, must be 1 */
358#define LEFT 2 /* left justified */
359#define PLUS 4 /* show plus */
360#define SPACE 8 /* space if plus */
361#define ZEROPAD 16 /* pad with zero, must be 16 == '0' - ' ' */
362#define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
363#define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
364
365enum format_type {
366 FORMAT_TYPE_NONE, /* Just a string part */
367 FORMAT_TYPE_WIDTH,
368 FORMAT_TYPE_PRECISION,
369 FORMAT_TYPE_CHAR,
370 FORMAT_TYPE_STR,
371 FORMAT_TYPE_PTR,
372 FORMAT_TYPE_PERCENT_CHAR,
373 FORMAT_TYPE_INVALID,
374 FORMAT_TYPE_LONG_LONG,
375 FORMAT_TYPE_ULONG,
376 FORMAT_TYPE_LONG,
377 FORMAT_TYPE_UBYTE,
378 FORMAT_TYPE_BYTE,
379 FORMAT_TYPE_USHORT,
380 FORMAT_TYPE_SHORT,
381 FORMAT_TYPE_UINT,
382 FORMAT_TYPE_INT,
383 FORMAT_TYPE_SIZE_T,
384 FORMAT_TYPE_PTRDIFF
385};
386
387struct printf_spec {
388 unsigned int type:8; /* format_type enum */
389 signed int field_width:24; /* width of output field */
390 unsigned int flags:8; /* flags to number() */
391 unsigned int base:8; /* number base, 8, 10 or 16 only */
392 signed int precision:16; /* # of digits/chars */
393} __packed;
394#define FIELD_WIDTH_MAX ((1 << 23) - 1)
395#define PRECISION_MAX ((1 << 15) - 1)
396
397static noinline_for_stack
398char *number(char *buf, char *end, unsigned long long num,
399 struct printf_spec spec)
400{
401 /* put_dec requires 2-byte alignment of the buffer. */
402 char tmp[3 * sizeof(num)] __aligned(2);
403 char sign;
404 char locase;
405 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
406 int i;
407 bool is_zero = num == 0LL;
408 int field_width = spec.field_width;
409 int precision = spec.precision;
410
411 BUILD_BUG_ON(sizeof(struct printf_spec) != 8);
412
413 /* locase = 0 or 0x20. ORing digits or letters with 'locase'
414 * produces same digits or (maybe lowercased) letters */
415 locase = (spec.flags & SMALL);
416 if (spec.flags & LEFT)
417 spec.flags &= ~ZEROPAD;
418 sign = 0;
419 if (spec.flags & SIGN) {
420 if ((signed long long)num < 0) {
421 sign = '-';
422 num = -(signed long long)num;
423 field_width--;
424 } else if (spec.flags & PLUS) {
425 sign = '+';
426 field_width--;
427 } else if (spec.flags & SPACE) {
428 sign = ' ';
429 field_width--;
430 }
431 }
432 if (need_pfx) {
433 if (spec.base == 16)
434 field_width -= 2;
435 else if (!is_zero)
436 field_width--;
437 }
438
439 /* generate full string in tmp[], in reverse order */
440 i = 0;
441 if (num < spec.base)
442 tmp[i++] = hex_asc_upper[num] | locase;
443 else if (spec.base != 10) { /* 8 or 16 */
444 int mask = spec.base - 1;
445 int shift = 3;
446
447 if (spec.base == 16)
448 shift = 4;
449 do {
450 tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase);
451 num >>= shift;
452 } while (num);
453 } else { /* base 10 */
454 i = put_dec(tmp, num) - tmp;
455 }
456
457 /* printing 100 using %2d gives "100", not "00" */
458 if (i > precision)
459 precision = i;
460 /* leading space padding */
461 field_width -= precision;
462 if (!(spec.flags & (ZEROPAD | LEFT))) {
463 while (--field_width >= 0) {
464 if (buf < end)
465 *buf = ' ';
466 ++buf;
467 }
468 }
469 /* sign */
470 if (sign) {
471 if (buf < end)
472 *buf = sign;
473 ++buf;
474 }
475 /* "0x" / "0" prefix */
476 if (need_pfx) {
477 if (spec.base == 16 || !is_zero) {
478 if (buf < end)
479 *buf = '0';
480 ++buf;
481 }
482 if (spec.base == 16) {
483 if (buf < end)
484 *buf = ('X' | locase);
485 ++buf;
486 }
487 }
488 /* zero or space padding */
489 if (!(spec.flags & LEFT)) {
490 char c = ' ' + (spec.flags & ZEROPAD);
491 BUILD_BUG_ON(' ' + ZEROPAD != '0');
492 while (--field_width >= 0) {
493 if (buf < end)
494 *buf = c;
495 ++buf;
496 }
497 }
498 /* hmm even more zero padding? */
499 while (i <= --precision) {
500 if (buf < end)
501 *buf = '0';
502 ++buf;
503 }
504 /* actual digits of result */
505 while (--i >= 0) {
506 if (buf < end)
507 *buf = tmp[i];
508 ++buf;
509 }
510 /* trailing space padding */
511 while (--field_width >= 0) {
512 if (buf < end)
513 *buf = ' ';
514 ++buf;
515 }
516
517 return buf;
518}
519
520static noinline_for_stack
521char *special_hex_number(char *buf, char *end, unsigned long long num, int size)
522{
523 struct printf_spec spec;
524
525 spec.type = FORMAT_TYPE_PTR;
526 spec.field_width = 2 + 2 * size; /* 0x + hex */
527 spec.flags = SPECIAL | SMALL | ZEROPAD;
528 spec.base = 16;
529 spec.precision = -1;
530
531 return number(buf, end, num, spec);
532}
533
534static void move_right(char *buf, char *end, unsigned len, unsigned spaces)
535{
536 size_t size;
537 if (buf >= end) /* nowhere to put anything */
538 return;
539 size = end - buf;
540 if (size <= spaces) {
541 memset(buf, ' ', size);
542 return;
543 }
544 if (len) {
545 if (len > size - spaces)
546 len = size - spaces;
547 memmove(buf + spaces, buf, len);
548 }
549 memset(buf, ' ', spaces);
550}
551
552/*
553 * Handle field width padding for a string.
554 * @buf: current buffer position
555 * @n: length of string
556 * @end: end of output buffer
557 * @spec: for field width and flags
558 * Returns: new buffer position after padding.
559 */
560static noinline_for_stack
561char *widen_string(char *buf, int n, char *end, struct printf_spec spec)
562{
563 unsigned spaces;
564
565 if (likely(n >= spec.field_width))
566 return buf;
567 /* we want to pad the sucker */
568 spaces = spec.field_width - n;
569 if (!(spec.flags & LEFT)) {
570 move_right(buf - n, end, n, spaces);
571 return buf + spaces;
572 }
573 while (spaces--) {
574 if (buf < end)
575 *buf = ' ';
576 ++buf;
577 }
578 return buf;
579}
580
581static noinline_for_stack
582char *string(char *buf, char *end, const char *s, struct printf_spec spec)
583{
584 int len = 0;
585 size_t lim = spec.precision;
586
587 if ((unsigned long)s < PAGE_SIZE)
588 s = "(null)";
589
590 while (lim--) {
591 char c = *s++;
592 if (!c)
593 break;
594 if (buf < end)
595 *buf = c;
596 ++buf;
597 ++len;
598 }
599 return widen_string(buf, len, end, spec);
600}
601
602static noinline_for_stack
603char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
604 const char *fmt)
605{
606 const char *array[4], *s;
607 const struct dentry *p;
608 int depth;
609 int i, n;
610
611 switch (fmt[1]) {
612 case '2': case '3': case '4':
613 depth = fmt[1] - '0';
614 break;
615 default:
616 depth = 1;
617 }
618
619 rcu_read_lock();
620 for (i = 0; i < depth; i++, d = p) {
621 p = ACCESS_ONCE(d->d_parent);
622 array[i] = ACCESS_ONCE(d->d_name.name);
623 if (p == d) {
624 if (i)
625 array[i] = "";
626 i++;
627 break;
628 }
629 }
630 s = array[--i];
631 for (n = 0; n != spec.precision; n++, buf++) {
632 char c = *s++;
633 if (!c) {
634 if (!i)
635 break;
636 c = '/';
637 s = array[--i];
638 }
639 if (buf < end)
640 *buf = c;
641 }
642 rcu_read_unlock();
643 return widen_string(buf, n, end, spec);
644}
645
646#ifdef CONFIG_BLOCK
647static noinline_for_stack
648char *bdev_name(char *buf, char *end, struct block_device *bdev,
649 struct printf_spec spec, const char *fmt)
650{
651 struct gendisk *hd = bdev->bd_disk;
652
653 buf = string(buf, end, hd->disk_name, spec);
654 if (bdev->bd_part->partno) {
655 if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) {
656 if (buf < end)
657 *buf = 'p';
658 buf++;
659 }
660 buf = number(buf, end, bdev->bd_part->partno, spec);
661 }
662 return buf;
663}
664#endif
665
666static noinline_for_stack
667char *symbol_string(char *buf, char *end, void *ptr,
668 struct printf_spec spec, const char *fmt)
669{
670 unsigned long value;
671#ifdef CONFIG_KALLSYMS
672 char sym[KSYM_SYMBOL_LEN];
673#endif
674
675 if (fmt[1] == 'R')
676 ptr = __builtin_extract_return_addr(ptr);
677 value = (unsigned long)ptr;
678
679#ifdef CONFIG_KALLSYMS
680 if (*fmt == 'B')
681 sprint_backtrace(sym, value);
682 else if (*fmt != 'f' && *fmt != 's')
683 sprint_symbol(sym, value);
684 else
685 sprint_symbol_no_offset(sym, value);
686
687 return string(buf, end, sym, spec);
688#else
689 return special_hex_number(buf, end, value, sizeof(void *));
690#endif
691}
692
693static noinline_for_stack
694char *resource_string(char *buf, char *end, struct resource *res,
695 struct printf_spec spec, const char *fmt)
696{
697#ifndef IO_RSRC_PRINTK_SIZE
698#define IO_RSRC_PRINTK_SIZE 6
699#endif
700
701#ifndef MEM_RSRC_PRINTK_SIZE
702#define MEM_RSRC_PRINTK_SIZE 10
703#endif
704 static const struct printf_spec io_spec = {
705 .base = 16,
706 .field_width = IO_RSRC_PRINTK_SIZE,
707 .precision = -1,
708 .flags = SPECIAL | SMALL | ZEROPAD,
709 };
710 static const struct printf_spec mem_spec = {
711 .base = 16,
712 .field_width = MEM_RSRC_PRINTK_SIZE,
713 .precision = -1,
714 .flags = SPECIAL | SMALL | ZEROPAD,
715 };
716 static const struct printf_spec bus_spec = {
717 .base = 16,
718 .field_width = 2,
719 .precision = -1,
720 .flags = SMALL | ZEROPAD,
721 };
722 static const struct printf_spec dec_spec = {
723 .base = 10,
724 .precision = -1,
725 .flags = 0,
726 };
727 static const struct printf_spec str_spec = {
728 .field_width = -1,
729 .precision = 10,
730 .flags = LEFT,
731 };
732 static const struct printf_spec flag_spec = {
733 .base = 16,
734 .precision = -1,
735 .flags = SPECIAL | SMALL,
736 };
737
738 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
739 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
740#define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
741#define FLAG_BUF_SIZE (2 * sizeof(res->flags))
742#define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
743#define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
744 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
745 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
746
747 char *p = sym, *pend = sym + sizeof(sym);
748 int decode = (fmt[0] == 'R') ? 1 : 0;
749 const struct printf_spec *specp;
750
751 *p++ = '[';
752 if (res->flags & IORESOURCE_IO) {
753 p = string(p, pend, "io ", str_spec);
754 specp = &io_spec;
755 } else if (res->flags & IORESOURCE_MEM) {
756 p = string(p, pend, "mem ", str_spec);
757 specp = &mem_spec;
758 } else if (res->flags & IORESOURCE_IRQ) {
759 p = string(p, pend, "irq ", str_spec);
760 specp = &dec_spec;
761 } else if (res->flags & IORESOURCE_DMA) {
762 p = string(p, pend, "dma ", str_spec);
763 specp = &dec_spec;
764 } else if (res->flags & IORESOURCE_BUS) {
765 p = string(p, pend, "bus ", str_spec);
766 specp = &bus_spec;
767 } else {
768 p = string(p, pend, "??? ", str_spec);
769 specp = &mem_spec;
770 decode = 0;
771 }
772 if (decode && res->flags & IORESOURCE_UNSET) {
773 p = string(p, pend, "size ", str_spec);
774 p = number(p, pend, resource_size(res), *specp);
775 } else {
776 p = number(p, pend, res->start, *specp);
777 if (res->start != res->end) {
778 *p++ = '-';
779 p = number(p, pend, res->end, *specp);
780 }
781 }
782 if (decode) {
783 if (res->flags & IORESOURCE_MEM_64)
784 p = string(p, pend, " 64bit", str_spec);
785 if (res->flags & IORESOURCE_PREFETCH)
786 p = string(p, pend, " pref", str_spec);
787 if (res->flags & IORESOURCE_WINDOW)
788 p = string(p, pend, " window", str_spec);
789 if (res->flags & IORESOURCE_DISABLED)
790 p = string(p, pend, " disabled", str_spec);
791 } else {
792 p = string(p, pend, " flags ", str_spec);
793 p = number(p, pend, res->flags, flag_spec);
794 }
795 *p++ = ']';
796 *p = '\0';
797
798 return string(buf, end, sym, spec);
799}
800
801static noinline_for_stack
802char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
803 const char *fmt)
804{
805 int i, len = 1; /* if we pass '%ph[CDN]', field width remains
806 negative value, fallback to the default */
807 char separator;
808
809 if (spec.field_width == 0)
810 /* nothing to print */
811 return buf;
812
813 if (ZERO_OR_NULL_PTR(addr))
814 /* NULL pointer */
815 return string(buf, end, NULL, spec);
816
817 switch (fmt[1]) {
818 case 'C':
819 separator = ':';
820 break;
821 case 'D':
822 separator = '-';
823 break;
824 case 'N':
825 separator = 0;
826 break;
827 default:
828 separator = ' ';
829 break;
830 }
831
832 if (spec.field_width > 0)
833 len = min_t(int, spec.field_width, 64);
834
835 for (i = 0; i < len; ++i) {
836 if (buf < end)
837 *buf = hex_asc_hi(addr[i]);
838 ++buf;
839 if (buf < end)
840 *buf = hex_asc_lo(addr[i]);
841 ++buf;
842
843 if (separator && i != len - 1) {
844 if (buf < end)
845 *buf = separator;
846 ++buf;
847 }
848 }
849
850 return buf;
851}
852
853static noinline_for_stack
854char *bitmap_string(char *buf, char *end, unsigned long *bitmap,
855 struct printf_spec spec, const char *fmt)
856{
857 const int CHUNKSZ = 32;
858 int nr_bits = max_t(int, spec.field_width, 0);
859 int i, chunksz;
860 bool first = true;
861
862 /* reused to print numbers */
863 spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 };
864
865 chunksz = nr_bits & (CHUNKSZ - 1);
866 if (chunksz == 0)
867 chunksz = CHUNKSZ;
868
869 i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ;
870 for (; i >= 0; i -= CHUNKSZ) {
871 u32 chunkmask, val;
872 int word, bit;
873
874 chunkmask = ((1ULL << chunksz) - 1);
875 word = i / BITS_PER_LONG;
876 bit = i % BITS_PER_LONG;
877 val = (bitmap[word] >> bit) & chunkmask;
878
879 if (!first) {
880 if (buf < end)
881 *buf = ',';
882 buf++;
883 }
884 first = false;
885
886 spec.field_width = DIV_ROUND_UP(chunksz, 4);
887 buf = number(buf, end, val, spec);
888
889 chunksz = CHUNKSZ;
890 }
891 return buf;
892}
893
894static noinline_for_stack
895char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap,
896 struct printf_spec spec, const char *fmt)
897{
898 int nr_bits = max_t(int, spec.field_width, 0);
899 /* current bit is 'cur', most recently seen range is [rbot, rtop] */
900 int cur, rbot, rtop;
901 bool first = true;
902
903 /* reused to print numbers */
904 spec = (struct printf_spec){ .base = 10 };
905
906 rbot = cur = find_first_bit(bitmap, nr_bits);
907 while (cur < nr_bits) {
908 rtop = cur;
909 cur = find_next_bit(bitmap, nr_bits, cur + 1);
910 if (cur < nr_bits && cur <= rtop + 1)
911 continue;
912
913 if (!first) {
914 if (buf < end)
915 *buf = ',';
916 buf++;
917 }
918 first = false;
919
920 buf = number(buf, end, rbot, spec);
921 if (rbot < rtop) {
922 if (buf < end)
923 *buf = '-';
924 buf++;
925
926 buf = number(buf, end, rtop, spec);
927 }
928
929 rbot = cur;
930 }
931 return buf;
932}
933
934static noinline_for_stack
935char *mac_address_string(char *buf, char *end, u8 *addr,
936 struct printf_spec spec, const char *fmt)
937{
938 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
939 char *p = mac_addr;
940 int i;
941 char separator;
942 bool reversed = false;
943
944 switch (fmt[1]) {
945 case 'F':
946 separator = '-';
947 break;
948
949 case 'R':
950 reversed = true;
951 /* fall through */
952
953 default:
954 separator = ':';
955 break;
956 }
957
958 for (i = 0; i < 6; i++) {
959 if (reversed)
960 p = hex_byte_pack(p, addr[5 - i]);
961 else
962 p = hex_byte_pack(p, addr[i]);
963
964 if (fmt[0] == 'M' && i != 5)
965 *p++ = separator;
966 }
967 *p = '\0';
968
969 return string(buf, end, mac_addr, spec);
970}
971
972static noinline_for_stack
973char *ip4_string(char *p, const u8 *addr, const char *fmt)
974{
975 int i;
976 bool leading_zeros = (fmt[0] == 'i');
977 int index;
978 int step;
979
980 switch (fmt[2]) {
981 case 'h':
982#ifdef __BIG_ENDIAN
983 index = 0;
984 step = 1;
985#else
986 index = 3;
987 step = -1;
988#endif
989 break;
990 case 'l':
991 index = 3;
992 step = -1;
993 break;
994 case 'n':
995 case 'b':
996 default:
997 index = 0;
998 step = 1;
999 break;
1000 }
1001 for (i = 0; i < 4; i++) {
1002 char temp[4] __aligned(2); /* hold each IP quad in reverse order */
1003 int digits = put_dec_trunc8(temp, addr[index]) - temp;
1004 if (leading_zeros) {
1005 if (digits < 3)
1006 *p++ = '0';
1007 if (digits < 2)
1008 *p++ = '0';
1009 }
1010 /* reverse the digits in the quad */
1011 while (digits--)
1012 *p++ = temp[digits];
1013 if (i < 3)
1014 *p++ = '.';
1015 index += step;
1016 }
1017 *p = '\0';
1018
1019 return p;
1020}
1021
1022static noinline_for_stack
1023char *ip6_compressed_string(char *p, const char *addr)
1024{
1025 int i, j, range;
1026 unsigned char zerolength[8];
1027 int longest = 1;
1028 int colonpos = -1;
1029 u16 word;
1030 u8 hi, lo;
1031 bool needcolon = false;
1032 bool useIPv4;
1033 struct in6_addr in6;
1034
1035 memcpy(&in6, addr, sizeof(struct in6_addr));
1036
1037 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
1038
1039 memset(zerolength, 0, sizeof(zerolength));
1040
1041 if (useIPv4)
1042 range = 6;
1043 else
1044 range = 8;
1045
1046 /* find position of longest 0 run */
1047 for (i = 0; i < range; i++) {
1048 for (j = i; j < range; j++) {
1049 if (in6.s6_addr16[j] != 0)
1050 break;
1051 zerolength[i]++;
1052 }
1053 }
1054 for (i = 0; i < range; i++) {
1055 if (zerolength[i] > longest) {
1056 longest = zerolength[i];
1057 colonpos = i;
1058 }
1059 }
1060 if (longest == 1) /* don't compress a single 0 */
1061 colonpos = -1;
1062
1063 /* emit address */
1064 for (i = 0; i < range; i++) {
1065 if (i == colonpos) {
1066 if (needcolon || i == 0)
1067 *p++ = ':';
1068 *p++ = ':';
1069 needcolon = false;
1070 i += longest - 1;
1071 continue;
1072 }
1073 if (needcolon) {
1074 *p++ = ':';
1075 needcolon = false;
1076 }
1077 /* hex u16 without leading 0s */
1078 word = ntohs(in6.s6_addr16[i]);
1079 hi = word >> 8;
1080 lo = word & 0xff;
1081 if (hi) {
1082 if (hi > 0x0f)
1083 p = hex_byte_pack(p, hi);
1084 else
1085 *p++ = hex_asc_lo(hi);
1086 p = hex_byte_pack(p, lo);
1087 }
1088 else if (lo > 0x0f)
1089 p = hex_byte_pack(p, lo);
1090 else
1091 *p++ = hex_asc_lo(lo);
1092 needcolon = true;
1093 }
1094
1095 if (useIPv4) {
1096 if (needcolon)
1097 *p++ = ':';
1098 p = ip4_string(p, &in6.s6_addr[12], "I4");
1099 }
1100 *p = '\0';
1101
1102 return p;
1103}
1104
1105static noinline_for_stack
1106char *ip6_string(char *p, const char *addr, const char *fmt)
1107{
1108 int i;
1109
1110 for (i = 0; i < 8; i++) {
1111 p = hex_byte_pack(p, *addr++);
1112 p = hex_byte_pack(p, *addr++);
1113 if (fmt[0] == 'I' && i != 7)
1114 *p++ = ':';
1115 }
1116 *p = '\0';
1117
1118 return p;
1119}
1120
1121static noinline_for_stack
1122char *ip6_addr_string(char *buf, char *end, const u8 *addr,
1123 struct printf_spec spec, const char *fmt)
1124{
1125 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
1126
1127 if (fmt[0] == 'I' && fmt[2] == 'c')
1128 ip6_compressed_string(ip6_addr, addr);
1129 else
1130 ip6_string(ip6_addr, addr, fmt);
1131
1132 return string(buf, end, ip6_addr, spec);
1133}
1134
1135static noinline_for_stack
1136char *ip4_addr_string(char *buf, char *end, const u8 *addr,
1137 struct printf_spec spec, const char *fmt)
1138{
1139 char ip4_addr[sizeof("255.255.255.255")];
1140
1141 ip4_string(ip4_addr, addr, fmt);
1142
1143 return string(buf, end, ip4_addr, spec);
1144}
1145
1146static noinline_for_stack
1147char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa,
1148 struct printf_spec spec, const char *fmt)
1149{
1150 bool have_p = false, have_s = false, have_f = false, have_c = false;
1151 char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") +
1152 sizeof(":12345") + sizeof("/123456789") +
1153 sizeof("%1234567890")];
1154 char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr);
1155 const u8 *addr = (const u8 *) &sa->sin6_addr;
1156 char fmt6[2] = { fmt[0], '6' };
1157 u8 off = 0;
1158
1159 fmt++;
1160 while (isalpha(*++fmt)) {
1161 switch (*fmt) {
1162 case 'p':
1163 have_p = true;
1164 break;
1165 case 'f':
1166 have_f = true;
1167 break;
1168 case 's':
1169 have_s = true;
1170 break;
1171 case 'c':
1172 have_c = true;
1173 break;
1174 }
1175 }
1176
1177 if (have_p || have_s || have_f) {
1178 *p = '[';
1179 off = 1;
1180 }
1181
1182 if (fmt6[0] == 'I' && have_c)
1183 p = ip6_compressed_string(ip6_addr + off, addr);
1184 else
1185 p = ip6_string(ip6_addr + off, addr, fmt6);
1186
1187 if (have_p || have_s || have_f)
1188 *p++ = ']';
1189
1190 if (have_p) {
1191 *p++ = ':';
1192 p = number(p, pend, ntohs(sa->sin6_port), spec);
1193 }
1194 if (have_f) {
1195 *p++ = '/';
1196 p = number(p, pend, ntohl(sa->sin6_flowinfo &
1197 IPV6_FLOWINFO_MASK), spec);
1198 }
1199 if (have_s) {
1200 *p++ = '%';
1201 p = number(p, pend, sa->sin6_scope_id, spec);
1202 }
1203 *p = '\0';
1204
1205 return string(buf, end, ip6_addr, spec);
1206}
1207
1208static noinline_for_stack
1209char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa,
1210 struct printf_spec spec, const char *fmt)
1211{
1212 bool have_p = false;
1213 char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")];
1214 char *pend = ip4_addr + sizeof(ip4_addr);
1215 const u8 *addr = (const u8 *) &sa->sin_addr.s_addr;
1216 char fmt4[3] = { fmt[0], '4', 0 };
1217
1218 fmt++;
1219 while (isalpha(*++fmt)) {
1220 switch (*fmt) {
1221 case 'p':
1222 have_p = true;
1223 break;
1224 case 'h':
1225 case 'l':
1226 case 'n':
1227 case 'b':
1228 fmt4[2] = *fmt;
1229 break;
1230 }
1231 }
1232
1233 p = ip4_string(ip4_addr, addr, fmt4);
1234 if (have_p) {
1235 *p++ = ':';
1236 p = number(p, pend, ntohs(sa->sin_port), spec);
1237 }
1238 *p = '\0';
1239
1240 return string(buf, end, ip4_addr, spec);
1241}
1242
1243static noinline_for_stack
1244char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1245 const char *fmt)
1246{
1247 bool found = true;
1248 int count = 1;
1249 unsigned int flags = 0;
1250 int len;
1251
1252 if (spec.field_width == 0)
1253 return buf; /* nothing to print */
1254
1255 if (ZERO_OR_NULL_PTR(addr))
1256 return string(buf, end, NULL, spec); /* NULL pointer */
1257
1258
1259 do {
1260 switch (fmt[count++]) {
1261 case 'a':
1262 flags |= ESCAPE_ANY;
1263 break;
1264 case 'c':
1265 flags |= ESCAPE_SPECIAL;
1266 break;
1267 case 'h':
1268 flags |= ESCAPE_HEX;
1269 break;
1270 case 'n':
1271 flags |= ESCAPE_NULL;
1272 break;
1273 case 'o':
1274 flags |= ESCAPE_OCTAL;
1275 break;
1276 case 'p':
1277 flags |= ESCAPE_NP;
1278 break;
1279 case 's':
1280 flags |= ESCAPE_SPACE;
1281 break;
1282 default:
1283 found = false;
1284 break;
1285 }
1286 } while (found);
1287
1288 if (!flags)
1289 flags = ESCAPE_ANY_NP;
1290
1291 len = spec.field_width < 0 ? 1 : spec.field_width;
1292
1293 /*
1294 * string_escape_mem() writes as many characters as it can to
1295 * the given buffer, and returns the total size of the output
1296 * had the buffer been big enough.
1297 */
1298 buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL);
1299
1300 return buf;
1301}
1302
1303static noinline_for_stack
1304char *uuid_string(char *buf, char *end, const u8 *addr,
1305 struct printf_spec spec, const char *fmt)
1306{
1307 char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")];
1308 char *p = uuid;
1309 int i;
1310 static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
1311 static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15};
1312 const u8 *index = be;
1313 bool uc = false;
1314
1315 switch (*(++fmt)) {
1316 case 'L':
1317 uc = true; /* fall-through */
1318 case 'l':
1319 index = le;
1320 break;
1321 case 'B':
1322 uc = true;
1323 break;
1324 }
1325
1326 for (i = 0; i < 16; i++) {
1327 p = hex_byte_pack(p, addr[index[i]]);
1328 switch (i) {
1329 case 3:
1330 case 5:
1331 case 7:
1332 case 9:
1333 *p++ = '-';
1334 break;
1335 }
1336 }
1337
1338 *p = 0;
1339
1340 if (uc) {
1341 p = uuid;
1342 do {
1343 *p = toupper(*p);
1344 } while (*(++p));
1345 }
1346
1347 return string(buf, end, uuid, spec);
1348}
1349
1350static noinline_for_stack
1351char *netdev_bits(char *buf, char *end, const void *addr, const char *fmt)
1352{
1353 unsigned long long num;
1354 int size;
1355
1356 switch (fmt[1]) {
1357 case 'F':
1358 num = *(const netdev_features_t *)addr;
1359 size = sizeof(netdev_features_t);
1360 break;
1361 default:
1362 num = (unsigned long)addr;
1363 size = sizeof(unsigned long);
1364 break;
1365 }
1366
1367 return special_hex_number(buf, end, num, size);
1368}
1369
1370static noinline_for_stack
1371char *address_val(char *buf, char *end, const void *addr, const char *fmt)
1372{
1373 unsigned long long num;
1374 int size;
1375
1376 switch (fmt[1]) {
1377 case 'd':
1378 num = *(const dma_addr_t *)addr;
1379 size = sizeof(dma_addr_t);
1380 break;
1381 case 'p':
1382 default:
1383 num = *(const phys_addr_t *)addr;
1384 size = sizeof(phys_addr_t);
1385 break;
1386 }
1387
1388 return special_hex_number(buf, end, num, size);
1389}
1390
1391static noinline_for_stack
1392char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec,
1393 const char *fmt)
1394{
1395 if (!IS_ENABLED(CONFIG_HAVE_CLK) || !clk)
1396 return string(buf, end, NULL, spec);
1397
1398 switch (fmt[1]) {
1399 case 'r':
1400 return number(buf, end, clk_get_rate(clk), spec);
1401
1402 case 'n':
1403 default:
1404#ifdef CONFIG_COMMON_CLK
1405 return string(buf, end, __clk_get_name(clk), spec);
1406#else
1407 return special_hex_number(buf, end, (unsigned long)clk, sizeof(unsigned long));
1408#endif
1409 }
1410}
1411
1412static
1413char *format_flags(char *buf, char *end, unsigned long flags,
1414 const struct trace_print_flags *names)
1415{
1416 unsigned long mask;
1417 const struct printf_spec strspec = {
1418 .field_width = -1,
1419 .precision = -1,
1420 };
1421 const struct printf_spec numspec = {
1422 .flags = SPECIAL|SMALL,
1423 .field_width = -1,
1424 .precision = -1,
1425 .base = 16,
1426 };
1427
1428 for ( ; flags && names->name; names++) {
1429 mask = names->mask;
1430 if ((flags & mask) != mask)
1431 continue;
1432
1433 buf = string(buf, end, names->name, strspec);
1434
1435 flags &= ~mask;
1436 if (flags) {
1437 if (buf < end)
1438 *buf = '|';
1439 buf++;
1440 }
1441 }
1442
1443 if (flags)
1444 buf = number(buf, end, flags, numspec);
1445
1446 return buf;
1447}
1448
1449static noinline_for_stack
1450char *flags_string(char *buf, char *end, void *flags_ptr, const char *fmt)
1451{
1452 unsigned long flags;
1453 const struct trace_print_flags *names;
1454
1455 switch (fmt[1]) {
1456 case 'p':
1457 flags = *(unsigned long *)flags_ptr;
1458 /* Remove zone id */
1459 flags &= (1UL << NR_PAGEFLAGS) - 1;
1460 names = pageflag_names;
1461 break;
1462 case 'v':
1463 flags = *(unsigned long *)flags_ptr;
1464 names = vmaflag_names;
1465 break;
1466 case 'g':
1467 flags = *(gfp_t *)flags_ptr;
1468 names = gfpflag_names;
1469 break;
1470 default:
1471 WARN_ONCE(1, "Unsupported flags modifier: %c\n", fmt[1]);
1472 return buf;
1473 }
1474
1475 return format_flags(buf, end, flags, names);
1476}
1477
1478int kptr_restrict __read_mostly;
1479
1480/*
1481 * Show a '%p' thing. A kernel extension is that the '%p' is followed
1482 * by an extra set of alphanumeric characters that are extended format
1483 * specifiers.
1484 *
1485 * Right now we handle:
1486 *
1487 * - 'F' For symbolic function descriptor pointers with offset
1488 * - 'f' For simple symbolic function names without offset
1489 * - 'S' For symbolic direct pointers with offset
1490 * - 's' For symbolic direct pointers without offset
1491 * - '[FfSs]R' as above with __builtin_extract_return_addr() translation
1492 * - 'B' For backtraced symbolic direct pointers with offset
1493 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
1494 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
1495 * - 'b[l]' For a bitmap, the number of bits is determined by the field
1496 * width which must be explicitly specified either as part of the
1497 * format string '%32b[l]' or through '%*b[l]', [l] selects
1498 * range-list format instead of hex format
1499 * - 'M' For a 6-byte MAC address, it prints the address in the
1500 * usual colon-separated hex notation
1501 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
1502 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
1503 * with a dash-separated hex notation
1504 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
1505 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
1506 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
1507 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
1508 * [S][pfs]
1509 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1510 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1511 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
1512 * IPv6 omits the colons (01020304...0f)
1513 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
1514 * [S][pfs]
1515 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1516 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1517 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
1518 * - 'I[6S]c' for IPv6 addresses printed as specified by
1519 * http://tools.ietf.org/html/rfc5952
1520 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination
1521 * of the following flags (see string_escape_mem() for the
1522 * details):
1523 * a - ESCAPE_ANY
1524 * c - ESCAPE_SPECIAL
1525 * h - ESCAPE_HEX
1526 * n - ESCAPE_NULL
1527 * o - ESCAPE_OCTAL
1528 * p - ESCAPE_NP
1529 * s - ESCAPE_SPACE
1530 * By default ESCAPE_ANY_NP is used.
1531 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
1532 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
1533 * Options for %pU are:
1534 * b big endian lower case hex (default)
1535 * B big endian UPPER case hex
1536 * l little endian lower case hex
1537 * L little endian UPPER case hex
1538 * big endian output byte order is:
1539 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
1540 * little endian output byte order is:
1541 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
1542 * - 'V' For a struct va_format which contains a format string * and va_list *,
1543 * call vsnprintf(->format, *->va_list).
1544 * Implements a "recursive vsnprintf".
1545 * Do not use this feature without some mechanism to verify the
1546 * correctness of the format string and va_list arguments.
1547 * - 'K' For a kernel pointer that should be hidden from unprivileged users
1548 * - 'NF' For a netdev_features_t
1549 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
1550 * a certain separator (' ' by default):
1551 * C colon
1552 * D dash
1553 * N no separator
1554 * The maximum supported length is 64 bytes of the input. Consider
1555 * to use print_hex_dump() for the larger input.
1556 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
1557 * (default assumed to be phys_addr_t, passed by reference)
1558 * - 'd[234]' For a dentry name (optionally 2-4 last components)
1559 * - 'D[234]' Same as 'd' but for a struct file
1560 * - 'g' For block_device name (gendisk + partition number)
1561 * - 'C' For a clock, it prints the name (Common Clock Framework) or address
1562 * (legacy clock framework) of the clock
1563 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address
1564 * (legacy clock framework) of the clock
1565 * - 'Cr' For a clock, it prints the current rate of the clock
1566 * - 'G' For flags to be printed as a collection of symbolic strings that would
1567 * construct the specific value. Supported flags given by option:
1568 * p page flags (see struct page) given as pointer to unsigned long
1569 * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t
1570 * v vma flags (VM_*) given as pointer to unsigned long
1571 *
1572 * ** Please update also Documentation/printk-formats.txt when making changes **
1573 *
1574 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
1575 * function pointers are really function descriptors, which contain a
1576 * pointer to the real address.
1577 */
1578static noinline_for_stack
1579char *pointer(const char *fmt, char *buf, char *end, void *ptr,
1580 struct printf_spec spec)
1581{
1582 const int default_width = 2 * sizeof(void *);
1583
1584 if (!ptr && *fmt != 'K') {
1585 /*
1586 * Print (null) with the same width as a pointer so it makes
1587 * tabular output look nice.
1588 */
1589 if (spec.field_width == -1)
1590 spec.field_width = default_width;
1591 return string(buf, end, "(null)", spec);
1592 }
1593
1594 switch (*fmt) {
1595 case 'F':
1596 case 'f':
1597 ptr = dereference_function_descriptor(ptr);
1598 /* Fallthrough */
1599 case 'S':
1600 case 's':
1601 case 'B':
1602 return symbol_string(buf, end, ptr, spec, fmt);
1603 case 'R':
1604 case 'r':
1605 return resource_string(buf, end, ptr, spec, fmt);
1606 case 'h':
1607 return hex_string(buf, end, ptr, spec, fmt);
1608 case 'b':
1609 switch (fmt[1]) {
1610 case 'l':
1611 return bitmap_list_string(buf, end, ptr, spec, fmt);
1612 default:
1613 return bitmap_string(buf, end, ptr, spec, fmt);
1614 }
1615 case 'M': /* Colon separated: 00:01:02:03:04:05 */
1616 case 'm': /* Contiguous: 000102030405 */
1617 /* [mM]F (FDDI) */
1618 /* [mM]R (Reverse order; Bluetooth) */
1619 return mac_address_string(buf, end, ptr, spec, fmt);
1620 case 'I': /* Formatted IP supported
1621 * 4: 1.2.3.4
1622 * 6: 0001:0203:...:0708
1623 * 6c: 1::708 or 1::1.2.3.4
1624 */
1625 case 'i': /* Contiguous:
1626 * 4: 001.002.003.004
1627 * 6: 000102...0f
1628 */
1629 switch (fmt[1]) {
1630 case '6':
1631 return ip6_addr_string(buf, end, ptr, spec, fmt);
1632 case '4':
1633 return ip4_addr_string(buf, end, ptr, spec, fmt);
1634 case 'S': {
1635 const union {
1636 struct sockaddr raw;
1637 struct sockaddr_in v4;
1638 struct sockaddr_in6 v6;
1639 } *sa = ptr;
1640
1641 switch (sa->raw.sa_family) {
1642 case AF_INET:
1643 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt);
1644 case AF_INET6:
1645 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt);
1646 default:
1647 return string(buf, end, "(invalid address)", spec);
1648 }}
1649 }
1650 break;
1651 case 'E':
1652 return escaped_string(buf, end, ptr, spec, fmt);
1653 case 'U':
1654 return uuid_string(buf, end, ptr, spec, fmt);
1655 case 'V':
1656 {
1657 va_list va;
1658
1659 va_copy(va, *((struct va_format *)ptr)->va);
1660 buf += vsnprintf(buf, end > buf ? end - buf : 0,
1661 ((struct va_format *)ptr)->fmt, va);
1662 va_end(va);
1663 return buf;
1664 }
1665 case 'K':
1666 switch (kptr_restrict) {
1667 case 0:
1668 /* Always print %pK values */
1669 break;
1670 case 1: {
1671 const struct cred *cred;
1672
1673 /*
1674 * kptr_restrict==1 cannot be used in IRQ context
1675 * because its test for CAP_SYSLOG would be meaningless.
1676 */
1677 if (in_irq() || in_serving_softirq() || in_nmi()) {
1678 if (spec.field_width == -1)
1679 spec.field_width = default_width;
1680 return string(buf, end, "pK-error", spec);
1681 }
1682
1683 /*
1684 * Only print the real pointer value if the current
1685 * process has CAP_SYSLOG and is running with the
1686 * same credentials it started with. This is because
1687 * access to files is checked at open() time, but %pK
1688 * checks permission at read() time. We don't want to
1689 * leak pointer values if a binary opens a file using
1690 * %pK and then elevates privileges before reading it.
1691 */
1692 cred = current_cred();
1693 if (!has_capability_noaudit(current, CAP_SYSLOG) ||
1694 !uid_eq(cred->euid, cred->uid) ||
1695 !gid_eq(cred->egid, cred->gid))
1696 ptr = NULL;
1697 break;
1698 }
1699 case 2:
1700 default:
1701 /* Always print 0's for %pK */
1702 ptr = NULL;
1703 break;
1704 }
1705 break;
1706
1707 case 'N':
1708 return netdev_bits(buf, end, ptr, fmt);
1709 case 'a':
1710 return address_val(buf, end, ptr, fmt);
1711 case 'd':
1712 return dentry_name(buf, end, ptr, spec, fmt);
1713 case 'C':
1714 return clock(buf, end, ptr, spec, fmt);
1715 case 'D':
1716 return dentry_name(buf, end,
1717 ((const struct file *)ptr)->f_path.dentry,
1718 spec, fmt);
1719#ifdef CONFIG_BLOCK
1720 case 'g':
1721 return bdev_name(buf, end, ptr, spec, fmt);
1722#endif
1723
1724 case 'G':
1725 return flags_string(buf, end, ptr, fmt);
1726 }
1727 spec.flags |= SMALL;
1728 if (spec.field_width == -1) {
1729 spec.field_width = default_width;
1730 spec.flags |= ZEROPAD;
1731 }
1732 spec.base = 16;
1733
1734 return number(buf, end, (unsigned long) ptr, spec);
1735}
1736
1737/*
1738 * Helper function to decode printf style format.
1739 * Each call decode a token from the format and return the
1740 * number of characters read (or likely the delta where it wants
1741 * to go on the next call).
1742 * The decoded token is returned through the parameters
1743 *
1744 * 'h', 'l', or 'L' for integer fields
1745 * 'z' support added 23/7/1999 S.H.
1746 * 'z' changed to 'Z' --davidm 1/25/99
1747 * 't' added for ptrdiff_t
1748 *
1749 * @fmt: the format string
1750 * @type of the token returned
1751 * @flags: various flags such as +, -, # tokens..
1752 * @field_width: overwritten width
1753 * @base: base of the number (octal, hex, ...)
1754 * @precision: precision of a number
1755 * @qualifier: qualifier of a number (long, size_t, ...)
1756 */
1757static noinline_for_stack
1758int format_decode(const char *fmt, struct printf_spec *spec)
1759{
1760 const char *start = fmt;
1761 char qualifier;
1762
1763 /* we finished early by reading the field width */
1764 if (spec->type == FORMAT_TYPE_WIDTH) {
1765 if (spec->field_width < 0) {
1766 spec->field_width = -spec->field_width;
1767 spec->flags |= LEFT;
1768 }
1769 spec->type = FORMAT_TYPE_NONE;
1770 goto precision;
1771 }
1772
1773 /* we finished early by reading the precision */
1774 if (spec->type == FORMAT_TYPE_PRECISION) {
1775 if (spec->precision < 0)
1776 spec->precision = 0;
1777
1778 spec->type = FORMAT_TYPE_NONE;
1779 goto qualifier;
1780 }
1781
1782 /* By default */
1783 spec->type = FORMAT_TYPE_NONE;
1784
1785 for (; *fmt ; ++fmt) {
1786 if (*fmt == '%')
1787 break;
1788 }
1789
1790 /* Return the current non-format string */
1791 if (fmt != start || !*fmt)
1792 return fmt - start;
1793
1794 /* Process flags */
1795 spec->flags = 0;
1796
1797 while (1) { /* this also skips first '%' */
1798 bool found = true;
1799
1800 ++fmt;
1801
1802 switch (*fmt) {
1803 case '-': spec->flags |= LEFT; break;
1804 case '+': spec->flags |= PLUS; break;
1805 case ' ': spec->flags |= SPACE; break;
1806 case '#': spec->flags |= SPECIAL; break;
1807 case '0': spec->flags |= ZEROPAD; break;
1808 default: found = false;
1809 }
1810
1811 if (!found)
1812 break;
1813 }
1814
1815 /* get field width */
1816 spec->field_width = -1;
1817
1818 if (isdigit(*fmt))
1819 spec->field_width = skip_atoi(&fmt);
1820 else if (*fmt == '*') {
1821 /* it's the next argument */
1822 spec->type = FORMAT_TYPE_WIDTH;
1823 return ++fmt - start;
1824 }
1825
1826precision:
1827 /* get the precision */
1828 spec->precision = -1;
1829 if (*fmt == '.') {
1830 ++fmt;
1831 if (isdigit(*fmt)) {
1832 spec->precision = skip_atoi(&fmt);
1833 if (spec->precision < 0)
1834 spec->precision = 0;
1835 } else if (*fmt == '*') {
1836 /* it's the next argument */
1837 spec->type = FORMAT_TYPE_PRECISION;
1838 return ++fmt - start;
1839 }
1840 }
1841
1842qualifier:
1843 /* get the conversion qualifier */
1844 qualifier = 0;
1845 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
1846 _tolower(*fmt) == 'z' || *fmt == 't') {
1847 qualifier = *fmt++;
1848 if (unlikely(qualifier == *fmt)) {
1849 if (qualifier == 'l') {
1850 qualifier = 'L';
1851 ++fmt;
1852 } else if (qualifier == 'h') {
1853 qualifier = 'H';
1854 ++fmt;
1855 }
1856 }
1857 }
1858
1859 /* default base */
1860 spec->base = 10;
1861 switch (*fmt) {
1862 case 'c':
1863 spec->type = FORMAT_TYPE_CHAR;
1864 return ++fmt - start;
1865
1866 case 's':
1867 spec->type = FORMAT_TYPE_STR;
1868 return ++fmt - start;
1869
1870 case 'p':
1871 spec->type = FORMAT_TYPE_PTR;
1872 return ++fmt - start;
1873
1874 case '%':
1875 spec->type = FORMAT_TYPE_PERCENT_CHAR;
1876 return ++fmt - start;
1877
1878 /* integer number formats - set up the flags and "break" */
1879 case 'o':
1880 spec->base = 8;
1881 break;
1882
1883 case 'x':
1884 spec->flags |= SMALL;
1885
1886 case 'X':
1887 spec->base = 16;
1888 break;
1889
1890 case 'd':
1891 case 'i':
1892 spec->flags |= SIGN;
1893 case 'u':
1894 break;
1895
1896 case 'n':
1897 /*
1898 * Since %n poses a greater security risk than
1899 * utility, treat it as any other invalid or
1900 * unsupported format specifier.
1901 */
1902 /* Fall-through */
1903
1904 default:
1905 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt);
1906 spec->type = FORMAT_TYPE_INVALID;
1907 return fmt - start;
1908 }
1909
1910 if (qualifier == 'L')
1911 spec->type = FORMAT_TYPE_LONG_LONG;
1912 else if (qualifier == 'l') {
1913 BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG);
1914 spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN);
1915 } else if (_tolower(qualifier) == 'z') {
1916 spec->type = FORMAT_TYPE_SIZE_T;
1917 } else if (qualifier == 't') {
1918 spec->type = FORMAT_TYPE_PTRDIFF;
1919 } else if (qualifier == 'H') {
1920 BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE);
1921 spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN);
1922 } else if (qualifier == 'h') {
1923 BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT);
1924 spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN);
1925 } else {
1926 BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT);
1927 spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN);
1928 }
1929
1930 return ++fmt - start;
1931}
1932
1933static void
1934set_field_width(struct printf_spec *spec, int width)
1935{
1936 spec->field_width = width;
1937 if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) {
1938 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX);
1939 }
1940}
1941
1942static void
1943set_precision(struct printf_spec *spec, int prec)
1944{
1945 spec->precision = prec;
1946 if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) {
1947 spec->precision = clamp(prec, 0, PRECISION_MAX);
1948 }
1949}
1950
1951/**
1952 * vsnprintf - Format a string and place it in a buffer
1953 * @buf: The buffer to place the result into
1954 * @size: The size of the buffer, including the trailing null space
1955 * @fmt: The format string to use
1956 * @args: Arguments for the format string
1957 *
1958 * This function generally follows C99 vsnprintf, but has some
1959 * extensions and a few limitations:
1960 *
1961 * %n is unsupported
1962 * %p* is handled by pointer()
1963 *
1964 * See pointer() or Documentation/printk-formats.txt for more
1965 * extensive description.
1966 *
1967 * ** Please update the documentation in both places when making changes **
1968 *
1969 * The return value is the number of characters which would
1970 * be generated for the given input, excluding the trailing
1971 * '\0', as per ISO C99. If you want to have the exact
1972 * number of characters written into @buf as return value
1973 * (not including the trailing '\0'), use vscnprintf(). If the
1974 * return is greater than or equal to @size, the resulting
1975 * string is truncated.
1976 *
1977 * If you're not already dealing with a va_list consider using snprintf().
1978 */
1979int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1980{
1981 unsigned long long num;
1982 char *str, *end;
1983 struct printf_spec spec = {0};
1984
1985 /* Reject out-of-range values early. Large positive sizes are
1986 used for unknown buffer sizes. */
1987 if (WARN_ON_ONCE(size > INT_MAX))
1988 return 0;
1989
1990 str = buf;
1991 end = buf + size;
1992
1993 /* Make sure end is always >= buf */
1994 if (end < buf) {
1995 end = ((void *)-1);
1996 size = end - buf;
1997 }
1998
1999 while (*fmt) {
2000 const char *old_fmt = fmt;
2001 int read = format_decode(fmt, &spec);
2002
2003 fmt += read;
2004
2005 switch (spec.type) {
2006 case FORMAT_TYPE_NONE: {
2007 int copy = read;
2008 if (str < end) {
2009 if (copy > end - str)
2010 copy = end - str;
2011 memcpy(str, old_fmt, copy);
2012 }
2013 str += read;
2014 break;
2015 }
2016
2017 case FORMAT_TYPE_WIDTH:
2018 set_field_width(&spec, va_arg(args, int));
2019 break;
2020
2021 case FORMAT_TYPE_PRECISION:
2022 set_precision(&spec, va_arg(args, int));
2023 break;
2024
2025 case FORMAT_TYPE_CHAR: {
2026 char c;
2027
2028 if (!(spec.flags & LEFT)) {
2029 while (--spec.field_width > 0) {
2030 if (str < end)
2031 *str = ' ';
2032 ++str;
2033
2034 }
2035 }
2036 c = (unsigned char) va_arg(args, int);
2037 if (str < end)
2038 *str = c;
2039 ++str;
2040 while (--spec.field_width > 0) {
2041 if (str < end)
2042 *str = ' ';
2043 ++str;
2044 }
2045 break;
2046 }
2047
2048 case FORMAT_TYPE_STR:
2049 str = string(str, end, va_arg(args, char *), spec);
2050 break;
2051
2052 case FORMAT_TYPE_PTR:
2053 str = pointer(fmt, str, end, va_arg(args, void *),
2054 spec);
2055 while (isalnum(*fmt))
2056 fmt++;
2057 break;
2058
2059 case FORMAT_TYPE_PERCENT_CHAR:
2060 if (str < end)
2061 *str = '%';
2062 ++str;
2063 break;
2064
2065 case FORMAT_TYPE_INVALID:
2066 /*
2067 * Presumably the arguments passed gcc's type
2068 * checking, but there is no safe or sane way
2069 * for us to continue parsing the format and
2070 * fetching from the va_list; the remaining
2071 * specifiers and arguments would be out of
2072 * sync.
2073 */
2074 goto out;
2075
2076 default:
2077 switch (spec.type) {
2078 case FORMAT_TYPE_LONG_LONG:
2079 num = va_arg(args, long long);
2080 break;
2081 case FORMAT_TYPE_ULONG:
2082 num = va_arg(args, unsigned long);
2083 break;
2084 case FORMAT_TYPE_LONG:
2085 num = va_arg(args, long);
2086 break;
2087 case FORMAT_TYPE_SIZE_T:
2088 if (spec.flags & SIGN)
2089 num = va_arg(args, ssize_t);
2090 else
2091 num = va_arg(args, size_t);
2092 break;
2093 case FORMAT_TYPE_PTRDIFF:
2094 num = va_arg(args, ptrdiff_t);
2095 break;
2096 case FORMAT_TYPE_UBYTE:
2097 num = (unsigned char) va_arg(args, int);
2098 break;
2099 case FORMAT_TYPE_BYTE:
2100 num = (signed char) va_arg(args, int);
2101 break;
2102 case FORMAT_TYPE_USHORT:
2103 num = (unsigned short) va_arg(args, int);
2104 break;
2105 case FORMAT_TYPE_SHORT:
2106 num = (short) va_arg(args, int);
2107 break;
2108 case FORMAT_TYPE_INT:
2109 num = (int) va_arg(args, int);
2110 break;
2111 default:
2112 num = va_arg(args, unsigned int);
2113 }
2114
2115 str = number(str, end, num, spec);
2116 }
2117 }
2118
2119out:
2120 if (size > 0) {
2121 if (str < end)
2122 *str = '\0';
2123 else
2124 end[-1] = '\0';
2125 }
2126
2127 /* the trailing null byte doesn't count towards the total */
2128 return str-buf;
2129
2130}
2131EXPORT_SYMBOL(vsnprintf);
2132
2133/**
2134 * vscnprintf - Format a string and place it in a buffer
2135 * @buf: The buffer to place the result into
2136 * @size: The size of the buffer, including the trailing null space
2137 * @fmt: The format string to use
2138 * @args: Arguments for the format string
2139 *
2140 * The return value is the number of characters which have been written into
2141 * the @buf not including the trailing '\0'. If @size is == 0 the function
2142 * returns 0.
2143 *
2144 * If you're not already dealing with a va_list consider using scnprintf().
2145 *
2146 * See the vsnprintf() documentation for format string extensions over C99.
2147 */
2148int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
2149{
2150 int i;
2151
2152 i = vsnprintf(buf, size, fmt, args);
2153
2154 if (likely(i < size))
2155 return i;
2156 if (size != 0)
2157 return size - 1;
2158 return 0;
2159}
2160EXPORT_SYMBOL(vscnprintf);
2161
2162/**
2163 * snprintf - Format a string and place it in a buffer
2164 * @buf: The buffer to place the result into
2165 * @size: The size of the buffer, including the trailing null space
2166 * @fmt: The format string to use
2167 * @...: Arguments for the format string
2168 *
2169 * The return value is the number of characters which would be
2170 * generated for the given input, excluding the trailing null,
2171 * as per ISO C99. If the return is greater than or equal to
2172 * @size, the resulting string is truncated.
2173 *
2174 * See the vsnprintf() documentation for format string extensions over C99.
2175 */
2176int snprintf(char *buf, size_t size, const char *fmt, ...)
2177{
2178 va_list args;
2179 int i;
2180
2181 va_start(args, fmt);
2182 i = vsnprintf(buf, size, fmt, args);
2183 va_end(args);
2184
2185 return i;
2186}
2187EXPORT_SYMBOL(snprintf);
2188
2189/**
2190 * scnprintf - Format a string and place it in a buffer
2191 * @buf: The buffer to place the result into
2192 * @size: The size of the buffer, including the trailing null space
2193 * @fmt: The format string to use
2194 * @...: Arguments for the format string
2195 *
2196 * The return value is the number of characters written into @buf not including
2197 * the trailing '\0'. If @size is == 0 the function returns 0.
2198 */
2199
2200int scnprintf(char *buf, size_t size, const char *fmt, ...)
2201{
2202 va_list args;
2203 int i;
2204
2205 va_start(args, fmt);
2206 i = vscnprintf(buf, size, fmt, args);
2207 va_end(args);
2208
2209 return i;
2210}
2211EXPORT_SYMBOL(scnprintf);
2212
2213/**
2214 * vsprintf - Format a string and place it in a buffer
2215 * @buf: The buffer to place the result into
2216 * @fmt: The format string to use
2217 * @args: Arguments for the format string
2218 *
2219 * The function returns the number of characters written
2220 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
2221 * buffer overflows.
2222 *
2223 * If you're not already dealing with a va_list consider using sprintf().
2224 *
2225 * See the vsnprintf() documentation for format string extensions over C99.
2226 */
2227int vsprintf(char *buf, const char *fmt, va_list args)
2228{
2229 return vsnprintf(buf, INT_MAX, fmt, args);
2230}
2231EXPORT_SYMBOL(vsprintf);
2232
2233/**
2234 * sprintf - Format a string and place it in a buffer
2235 * @buf: The buffer to place the result into
2236 * @fmt: The format string to use
2237 * @...: Arguments for the format string
2238 *
2239 * The function returns the number of characters written
2240 * into @buf. Use snprintf() or scnprintf() in order to avoid
2241 * buffer overflows.
2242 *
2243 * See the vsnprintf() documentation for format string extensions over C99.
2244 */
2245int sprintf(char *buf, const char *fmt, ...)
2246{
2247 va_list args;
2248 int i;
2249
2250 va_start(args, fmt);
2251 i = vsnprintf(buf, INT_MAX, fmt, args);
2252 va_end(args);
2253
2254 return i;
2255}
2256EXPORT_SYMBOL(sprintf);
2257
2258#ifdef CONFIG_BINARY_PRINTF
2259/*
2260 * bprintf service:
2261 * vbin_printf() - VA arguments to binary data
2262 * bstr_printf() - Binary data to text string
2263 */
2264
2265/**
2266 * vbin_printf - Parse a format string and place args' binary value in a buffer
2267 * @bin_buf: The buffer to place args' binary value
2268 * @size: The size of the buffer(by words(32bits), not characters)
2269 * @fmt: The format string to use
2270 * @args: Arguments for the format string
2271 *
2272 * The format follows C99 vsnprintf, except %n is ignored, and its argument
2273 * is skipped.
2274 *
2275 * The return value is the number of words(32bits) which would be generated for
2276 * the given input.
2277 *
2278 * NOTE:
2279 * If the return value is greater than @size, the resulting bin_buf is NOT
2280 * valid for bstr_printf().
2281 */
2282int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
2283{
2284 struct printf_spec spec = {0};
2285 char *str, *end;
2286
2287 str = (char *)bin_buf;
2288 end = (char *)(bin_buf + size);
2289
2290#define save_arg(type) \
2291do { \
2292 if (sizeof(type) == 8) { \
2293 unsigned long long value; \
2294 str = PTR_ALIGN(str, sizeof(u32)); \
2295 value = va_arg(args, unsigned long long); \
2296 if (str + sizeof(type) <= end) { \
2297 *(u32 *)str = *(u32 *)&value; \
2298 *(u32 *)(str + 4) = *((u32 *)&value + 1); \
2299 } \
2300 } else { \
2301 unsigned long value; \
2302 str = PTR_ALIGN(str, sizeof(type)); \
2303 value = va_arg(args, int); \
2304 if (str + sizeof(type) <= end) \
2305 *(typeof(type) *)str = (type)value; \
2306 } \
2307 str += sizeof(type); \
2308} while (0)
2309
2310 while (*fmt) {
2311 int read = format_decode(fmt, &spec);
2312
2313 fmt += read;
2314
2315 switch (spec.type) {
2316 case FORMAT_TYPE_NONE:
2317 case FORMAT_TYPE_PERCENT_CHAR:
2318 break;
2319 case FORMAT_TYPE_INVALID:
2320 goto out;
2321
2322 case FORMAT_TYPE_WIDTH:
2323 case FORMAT_TYPE_PRECISION:
2324 save_arg(int);
2325 break;
2326
2327 case FORMAT_TYPE_CHAR:
2328 save_arg(char);
2329 break;
2330
2331 case FORMAT_TYPE_STR: {
2332 const char *save_str = va_arg(args, char *);
2333 size_t len;
2334
2335 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
2336 || (unsigned long)save_str < PAGE_SIZE)
2337 save_str = "(null)";
2338 len = strlen(save_str) + 1;
2339 if (str + len < end)
2340 memcpy(str, save_str, len);
2341 str += len;
2342 break;
2343 }
2344
2345 case FORMAT_TYPE_PTR:
2346 save_arg(void *);
2347 /* skip all alphanumeric pointer suffixes */
2348 while (isalnum(*fmt))
2349 fmt++;
2350 break;
2351
2352 default:
2353 switch (spec.type) {
2354
2355 case FORMAT_TYPE_LONG_LONG:
2356 save_arg(long long);
2357 break;
2358 case FORMAT_TYPE_ULONG:
2359 case FORMAT_TYPE_LONG:
2360 save_arg(unsigned long);
2361 break;
2362 case FORMAT_TYPE_SIZE_T:
2363 save_arg(size_t);
2364 break;
2365 case FORMAT_TYPE_PTRDIFF:
2366 save_arg(ptrdiff_t);
2367 break;
2368 case FORMAT_TYPE_UBYTE:
2369 case FORMAT_TYPE_BYTE:
2370 save_arg(char);
2371 break;
2372 case FORMAT_TYPE_USHORT:
2373 case FORMAT_TYPE_SHORT:
2374 save_arg(short);
2375 break;
2376 default:
2377 save_arg(int);
2378 }
2379 }
2380 }
2381
2382out:
2383 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
2384#undef save_arg
2385}
2386EXPORT_SYMBOL_GPL(vbin_printf);
2387
2388/**
2389 * bstr_printf - Format a string from binary arguments and place it in a buffer
2390 * @buf: The buffer to place the result into
2391 * @size: The size of the buffer, including the trailing null space
2392 * @fmt: The format string to use
2393 * @bin_buf: Binary arguments for the format string
2394 *
2395 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
2396 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
2397 * a binary buffer that generated by vbin_printf.
2398 *
2399 * The format follows C99 vsnprintf, but has some extensions:
2400 * see vsnprintf comment for details.
2401 *
2402 * The return value is the number of characters which would
2403 * be generated for the given input, excluding the trailing
2404 * '\0', as per ISO C99. If you want to have the exact
2405 * number of characters written into @buf as return value
2406 * (not including the trailing '\0'), use vscnprintf(). If the
2407 * return is greater than or equal to @size, the resulting
2408 * string is truncated.
2409 */
2410int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
2411{
2412 struct printf_spec spec = {0};
2413 char *str, *end;
2414 const char *args = (const char *)bin_buf;
2415
2416 if (WARN_ON_ONCE(size > INT_MAX))
2417 return 0;
2418
2419 str = buf;
2420 end = buf + size;
2421
2422#define get_arg(type) \
2423({ \
2424 typeof(type) value; \
2425 if (sizeof(type) == 8) { \
2426 args = PTR_ALIGN(args, sizeof(u32)); \
2427 *(u32 *)&value = *(u32 *)args; \
2428 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
2429 } else { \
2430 args = PTR_ALIGN(args, sizeof(type)); \
2431 value = *(typeof(type) *)args; \
2432 } \
2433 args += sizeof(type); \
2434 value; \
2435})
2436
2437 /* Make sure end is always >= buf */
2438 if (end < buf) {
2439 end = ((void *)-1);
2440 size = end - buf;
2441 }
2442
2443 while (*fmt) {
2444 const char *old_fmt = fmt;
2445 int read = format_decode(fmt, &spec);
2446
2447 fmt += read;
2448
2449 switch (spec.type) {
2450 case FORMAT_TYPE_NONE: {
2451 int copy = read;
2452 if (str < end) {
2453 if (copy > end - str)
2454 copy = end - str;
2455 memcpy(str, old_fmt, copy);
2456 }
2457 str += read;
2458 break;
2459 }
2460
2461 case FORMAT_TYPE_WIDTH:
2462 set_field_width(&spec, get_arg(int));
2463 break;
2464
2465 case FORMAT_TYPE_PRECISION:
2466 set_precision(&spec, get_arg(int));
2467 break;
2468
2469 case FORMAT_TYPE_CHAR: {
2470 char c;
2471
2472 if (!(spec.flags & LEFT)) {
2473 while (--spec.field_width > 0) {
2474 if (str < end)
2475 *str = ' ';
2476 ++str;
2477 }
2478 }
2479 c = (unsigned char) get_arg(char);
2480 if (str < end)
2481 *str = c;
2482 ++str;
2483 while (--spec.field_width > 0) {
2484 if (str < end)
2485 *str = ' ';
2486 ++str;
2487 }
2488 break;
2489 }
2490
2491 case FORMAT_TYPE_STR: {
2492 const char *str_arg = args;
2493 args += strlen(str_arg) + 1;
2494 str = string(str, end, (char *)str_arg, spec);
2495 break;
2496 }
2497
2498 case FORMAT_TYPE_PTR:
2499 str = pointer(fmt, str, end, get_arg(void *), spec);
2500 while (isalnum(*fmt))
2501 fmt++;
2502 break;
2503
2504 case FORMAT_TYPE_PERCENT_CHAR:
2505 if (str < end)
2506 *str = '%';
2507 ++str;
2508 break;
2509
2510 case FORMAT_TYPE_INVALID:
2511 goto out;
2512
2513 default: {
2514 unsigned long long num;
2515
2516 switch (spec.type) {
2517
2518 case FORMAT_TYPE_LONG_LONG:
2519 num = get_arg(long long);
2520 break;
2521 case FORMAT_TYPE_ULONG:
2522 case FORMAT_TYPE_LONG:
2523 num = get_arg(unsigned long);
2524 break;
2525 case FORMAT_TYPE_SIZE_T:
2526 num = get_arg(size_t);
2527 break;
2528 case FORMAT_TYPE_PTRDIFF:
2529 num = get_arg(ptrdiff_t);
2530 break;
2531 case FORMAT_TYPE_UBYTE:
2532 num = get_arg(unsigned char);
2533 break;
2534 case FORMAT_TYPE_BYTE:
2535 num = get_arg(signed char);
2536 break;
2537 case FORMAT_TYPE_USHORT:
2538 num = get_arg(unsigned short);
2539 break;
2540 case FORMAT_TYPE_SHORT:
2541 num = get_arg(short);
2542 break;
2543 case FORMAT_TYPE_UINT:
2544 num = get_arg(unsigned int);
2545 break;
2546 default:
2547 num = get_arg(int);
2548 }
2549
2550 str = number(str, end, num, spec);
2551 } /* default: */
2552 } /* switch(spec.type) */
2553 } /* while(*fmt) */
2554
2555out:
2556 if (size > 0) {
2557 if (str < end)
2558 *str = '\0';
2559 else
2560 end[-1] = '\0';
2561 }
2562
2563#undef get_arg
2564
2565 /* the trailing null byte doesn't count towards the total */
2566 return str - buf;
2567}
2568EXPORT_SYMBOL_GPL(bstr_printf);
2569
2570/**
2571 * bprintf - Parse a format string and place args' binary value in a buffer
2572 * @bin_buf: The buffer to place args' binary value
2573 * @size: The size of the buffer(by words(32bits), not characters)
2574 * @fmt: The format string to use
2575 * @...: Arguments for the format string
2576 *
2577 * The function returns the number of words(u32) written
2578 * into @bin_buf.
2579 */
2580int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
2581{
2582 va_list args;
2583 int ret;
2584
2585 va_start(args, fmt);
2586 ret = vbin_printf(bin_buf, size, fmt, args);
2587 va_end(args);
2588
2589 return ret;
2590}
2591EXPORT_SYMBOL_GPL(bprintf);
2592
2593#endif /* CONFIG_BINARY_PRINTF */
2594
2595/**
2596 * vsscanf - Unformat a buffer into a list of arguments
2597 * @buf: input buffer
2598 * @fmt: format of buffer
2599 * @args: arguments
2600 */
2601int vsscanf(const char *buf, const char *fmt, va_list args)
2602{
2603 const char *str = buf;
2604 char *next;
2605 char digit;
2606 int num = 0;
2607 u8 qualifier;
2608 unsigned int base;
2609 union {
2610 long long s;
2611 unsigned long long u;
2612 } val;
2613 s16 field_width;
2614 bool is_sign;
2615
2616 while (*fmt) {
2617 /* skip any white space in format */
2618 /* white space in format matchs any amount of
2619 * white space, including none, in the input.
2620 */
2621 if (isspace(*fmt)) {
2622 fmt = skip_spaces(++fmt);
2623 str = skip_spaces(str);
2624 }
2625
2626 /* anything that is not a conversion must match exactly */
2627 if (*fmt != '%' && *fmt) {
2628 if (*fmt++ != *str++)
2629 break;
2630 continue;
2631 }
2632
2633 if (!*fmt)
2634 break;
2635 ++fmt;
2636
2637 /* skip this conversion.
2638 * advance both strings to next white space
2639 */
2640 if (*fmt == '*') {
2641 if (!*str)
2642 break;
2643 while (!isspace(*fmt) && *fmt != '%' && *fmt) {
2644 /* '%*[' not yet supported, invalid format */
2645 if (*fmt == '[')
2646 return num;
2647 fmt++;
2648 }
2649 while (!isspace(*str) && *str)
2650 str++;
2651 continue;
2652 }
2653
2654 /* get field width */
2655 field_width = -1;
2656 if (isdigit(*fmt)) {
2657 field_width = skip_atoi(&fmt);
2658 if (field_width <= 0)
2659 break;
2660 }
2661
2662 /* get conversion qualifier */
2663 qualifier = -1;
2664 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
2665 _tolower(*fmt) == 'z') {
2666 qualifier = *fmt++;
2667 if (unlikely(qualifier == *fmt)) {
2668 if (qualifier == 'h') {
2669 qualifier = 'H';
2670 fmt++;
2671 } else if (qualifier == 'l') {
2672 qualifier = 'L';
2673 fmt++;
2674 }
2675 }
2676 }
2677
2678 if (!*fmt)
2679 break;
2680
2681 if (*fmt == 'n') {
2682 /* return number of characters read so far */
2683 *va_arg(args, int *) = str - buf;
2684 ++fmt;
2685 continue;
2686 }
2687
2688 if (!*str)
2689 break;
2690
2691 base = 10;
2692 is_sign = false;
2693
2694 switch (*fmt++) {
2695 case 'c':
2696 {
2697 char *s = (char *)va_arg(args, char*);
2698 if (field_width == -1)
2699 field_width = 1;
2700 do {
2701 *s++ = *str++;
2702 } while (--field_width > 0 && *str);
2703 num++;
2704 }
2705 continue;
2706 case 's':
2707 {
2708 char *s = (char *)va_arg(args, char *);
2709 if (field_width == -1)
2710 field_width = SHRT_MAX;
2711 /* first, skip leading white space in buffer */
2712 str = skip_spaces(str);
2713
2714 /* now copy until next white space */
2715 while (*str && !isspace(*str) && field_width--)
2716 *s++ = *str++;
2717 *s = '\0';
2718 num++;
2719 }
2720 continue;
2721 /*
2722 * Warning: This implementation of the '[' conversion specifier
2723 * deviates from its glibc counterpart in the following ways:
2724 * (1) It does NOT support ranges i.e. '-' is NOT a special
2725 * character
2726 * (2) It cannot match the closing bracket ']' itself
2727 * (3) A field width is required
2728 * (4) '%*[' (discard matching input) is currently not supported
2729 *
2730 * Example usage:
2731 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]",
2732 * buf1, buf2, buf3);
2733 * if (ret < 3)
2734 * // etc..
2735 */
2736 case '[':
2737 {
2738 char *s = (char *)va_arg(args, char *);
2739 DECLARE_BITMAP(set, 256) = {0};
2740 unsigned int len = 0;
2741 bool negate = (*fmt == '^');
2742
2743 /* field width is required */
2744 if (field_width == -1)
2745 return num;
2746
2747 if (negate)
2748 ++fmt;
2749
2750 for ( ; *fmt && *fmt != ']'; ++fmt, ++len)
2751 set_bit((u8)*fmt, set);
2752
2753 /* no ']' or no character set found */
2754 if (!*fmt || !len)
2755 return num;
2756 ++fmt;
2757
2758 if (negate) {
2759 bitmap_complement(set, set, 256);
2760 /* exclude null '\0' byte */
2761 clear_bit(0, set);
2762 }
2763
2764 /* match must be non-empty */
2765 if (!test_bit((u8)*str, set))
2766 return num;
2767
2768 while (test_bit((u8)*str, set) && field_width--)
2769 *s++ = *str++;
2770 *s = '\0';
2771 ++num;
2772 }
2773 continue;
2774 case 'o':
2775 base = 8;
2776 break;
2777 case 'x':
2778 case 'X':
2779 base = 16;
2780 break;
2781 case 'i':
2782 base = 0;
2783 case 'd':
2784 is_sign = true;
2785 case 'u':
2786 break;
2787 case '%':
2788 /* looking for '%' in str */
2789 if (*str++ != '%')
2790 return num;
2791 continue;
2792 default:
2793 /* invalid format; stop here */
2794 return num;
2795 }
2796
2797 /* have some sort of integer conversion.
2798 * first, skip white space in buffer.
2799 */
2800 str = skip_spaces(str);
2801
2802 digit = *str;
2803 if (is_sign && digit == '-')
2804 digit = *(str + 1);
2805
2806 if (!digit
2807 || (base == 16 && !isxdigit(digit))
2808 || (base == 10 && !isdigit(digit))
2809 || (base == 8 && (!isdigit(digit) || digit > '7'))
2810 || (base == 0 && !isdigit(digit)))
2811 break;
2812
2813 if (is_sign)
2814 val.s = qualifier != 'L' ?
2815 simple_strtol(str, &next, base) :
2816 simple_strtoll(str, &next, base);
2817 else
2818 val.u = qualifier != 'L' ?
2819 simple_strtoul(str, &next, base) :
2820 simple_strtoull(str, &next, base);
2821
2822 if (field_width > 0 && next - str > field_width) {
2823 if (base == 0)
2824 _parse_integer_fixup_radix(str, &base);
2825 while (next - str > field_width) {
2826 if (is_sign)
2827 val.s = div_s64(val.s, base);
2828 else
2829 val.u = div_u64(val.u, base);
2830 --next;
2831 }
2832 }
2833
2834 switch (qualifier) {
2835 case 'H': /* that's 'hh' in format */
2836 if (is_sign)
2837 *va_arg(args, signed char *) = val.s;
2838 else
2839 *va_arg(args, unsigned char *) = val.u;
2840 break;
2841 case 'h':
2842 if (is_sign)
2843 *va_arg(args, short *) = val.s;
2844 else
2845 *va_arg(args, unsigned short *) = val.u;
2846 break;
2847 case 'l':
2848 if (is_sign)
2849 *va_arg(args, long *) = val.s;
2850 else
2851 *va_arg(args, unsigned long *) = val.u;
2852 break;
2853 case 'L':
2854 if (is_sign)
2855 *va_arg(args, long long *) = val.s;
2856 else
2857 *va_arg(args, unsigned long long *) = val.u;
2858 break;
2859 case 'Z':
2860 case 'z':
2861 *va_arg(args, size_t *) = val.u;
2862 break;
2863 default:
2864 if (is_sign)
2865 *va_arg(args, int *) = val.s;
2866 else
2867 *va_arg(args, unsigned int *) = val.u;
2868 break;
2869 }
2870 num++;
2871
2872 if (!next)
2873 break;
2874 str = next;
2875 }
2876
2877 return num;
2878}
2879EXPORT_SYMBOL(vsscanf);
2880
2881/**
2882 * sscanf - Unformat a buffer into a list of arguments
2883 * @buf: input buffer
2884 * @fmt: formatting of buffer
2885 * @...: resulting arguments
2886 */
2887int sscanf(const char *buf, const char *fmt, ...)
2888{
2889 va_list args;
2890 int i;
2891
2892 va_start(args, fmt);
2893 i = vsscanf(buf, fmt, args);
2894 va_end(args);
2895
2896 return i;
2897}
2898EXPORT_SYMBOL(sscanf);