1 
2 #include <xen/ctype.h>
3 #include <xen/lib.h>
4 #include <xen/types.h>
5 #include <xen/init.h>
6 #include <asm/byteorder.h>
7 
8 /* for ctype.h */
9 const unsigned char _ctype[] = {
10     _C,_C,_C,_C,_C,_C,_C,_C,                        /* 0-7 */
11     _C,_C|_S,_C|_S,_C|_S,_C|_S,_C|_S,_C,_C,         /* 8-15 */
12     _C,_C,_C,_C,_C,_C,_C,_C,                        /* 16-23 */
13     _C,_C,_C,_C,_C,_C,_C,_C,                        /* 24-31 */
14     _S|_SP,_P,_P,_P,_P,_P,_P,_P,                    /* 32-39 */
15     _P,_P,_P,_P,_P,_P,_P,_P,                        /* 40-47 */
16     _D,_D,_D,_D,_D,_D,_D,_D,                        /* 48-55 */
17     _D,_D,_P,_P,_P,_P,_P,_P,                        /* 56-63 */
18     _P,_U|_X,_U|_X,_U|_X,_U|_X,_U|_X,_U|_X,_U,      /* 64-71 */
19     _U,_U,_U,_U,_U,_U,_U,_U,                        /* 72-79 */
20     _U,_U,_U,_U,_U,_U,_U,_U,                        /* 80-87 */
21     _U,_U,_U,_P,_P,_P,_P,_P,                        /* 88-95 */
22     _P,_L|_X,_L|_X,_L|_X,_L|_X,_L|_X,_L|_X,_L,      /* 96-103 */
23     _L,_L,_L,_L,_L,_L,_L,_L,                        /* 104-111 */
24     _L,_L,_L,_L,_L,_L,_L,_L,                        /* 112-119 */
25     _L,_L,_L,_P,_P,_P,_P,_C,                        /* 120-127 */
26     0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,                /* 128-143 */
27     0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,                /* 144-159 */
28     _S|_SP,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,   /* 160-175 */
29     _P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,       /* 176-191 */
30     _U,_U,_U,_U,_U,_U,_U,_U,_U,_U,_U,_U,_U,_U,_U,_U,       /* 192-207 */
31     _U,_U,_U,_U,_U,_U,_U,_P,_U,_U,_U,_U,_U,_U,_U,_L,       /* 208-223 */
32     _L,_L,_L,_L,_L,_L,_L,_L,_L,_L,_L,_L,_L,_L,_L,_L,       /* 224-239 */
33     _L,_L,_L,_L,_L,_L,_L,_P,_L,_L,_L,_L,_L,_L,_L,_L};      /* 240-255 */
34 
35 /*
36  * A couple of 64 bit operations ported from FreeBSD.
37  * The code within the '#if BITS_PER_LONG == 32' block below, and no other
38  * code in this file, is distributed under the following licensing terms
39  * This is the modified '3-clause' BSD license with the obnoxious
40  * advertising clause removed, as permitted by University of California.
41  *
42  * Copyright (c) 1992, 1993
43  * The Regents of the University of California.  All rights reserved.
44  *
45  * This software was developed by the Computer Systems Engineering group
46  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
47  * contributed to Berkeley.
48  *
49  * Redistribution and use in source and binary forms, with or without
50  * modification, are permitted provided that the following conditions
51  * are met:
52  * 1. Redistributions of source code must retain the above copyright
53  *    notice, this list of conditions and the following disclaimer.
54  * 2. Redistributions in binary form must reproduce the above copyright
55  *    notice, this list of conditions and the following disclaimer in the
56  *    documentation and/or other materials provided with the distribution.
57  * 3. Neither the name of the University nor the names of its contributors
58  *    may be used to endorse or promote products derived from this software
59  *    without specific prior written permission.
60  *
61  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
62  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
63  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
64  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
65  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
66  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
67  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
68  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
69  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
70  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
71  * SUCH DAMAGE.
72  */
73 #if BITS_PER_LONG == 32
74 
75 /*
76  * Depending on the desired operation, we view a `long long' (aka quad_t) in
77  * one or more of the following formats.
78  */
79 union uu {
80     s64            q;              /* as a (signed) quad */
81     s64            uq;             /* as an unsigned quad */
82     long           sl[2];          /* as two signed longs */
83     unsigned long  ul[2];          /* as two unsigned longs */
84 };
85 
86 #ifdef __BIG_ENDIAN
87 #define _QUAD_HIGHWORD 0
88 #define _QUAD_LOWWORD 1
89 #else /* __LITTLE_ENDIAN */
90 #define _QUAD_HIGHWORD 1
91 #define _QUAD_LOWWORD 0
92 #endif
93 
94 /*
95  * Define high and low longwords.
96  */
97 #define H               _QUAD_HIGHWORD
98 #define L               _QUAD_LOWWORD
99 
100 /*
101  * Total number of bits in a quad_t and in the pieces that make it up.
102  * These are used for shifting, and also below for halfword extraction
103  * and assembly.
104  */
105 #define CHAR_BIT        8               /* number of bits in a char */
106 #define QUAD_BITS       (sizeof(s64) * CHAR_BIT)
107 #define LONG_BITS       (sizeof(long) * CHAR_BIT)
108 #define HALF_BITS       (sizeof(long) * CHAR_BIT / 2)
109 
110 /*
111  * Extract high and low shortwords from longword, and move low shortword of
112  * longword to upper half of long, i.e., produce the upper longword of
113  * ((quad_t)(x) << (number_of_bits_in_long/2)).  (`x' must actually be
114  * unsigned long.)
115  *
116  * These are used in the multiply code, to split a longword into upper
117  * and lower halves, and to reassemble a product as a quad_t, shifted left
118  * (sizeof(long)*CHAR_BIT/2).
119  */
120 #define HHALF(x)        ((x) >> HALF_BITS)
121 #define LHALF(x)        ((x) & ((1 << HALF_BITS) - 1))
122 #define LHUP(x)         ((x) << HALF_BITS)
123 
124 /*
125  * Multiprecision divide.  This algorithm is from Knuth vol. 2 (2nd ed),
126  * section 4.3.1, pp. 257--259.
127  */
128 #define B (1 << HALF_BITS) /* digit base */
129 
130 /* Combine two `digits' to make a single two-digit number. */
131 #define COMBINE(a, b) (((unsigned long)(a) << HALF_BITS) | (b))
132 
133 /* select a type for digits in base B */
134 typedef unsigned long digit;
135 
136 /*
137  * Shift p[0]..p[len] left `sh' bits, ignoring any bits that
138  * `fall out' the left (there never will be any such anyway).
139  * We may assume len >= 0.  NOTE THAT THIS WRITES len+1 DIGITS.
140  */
shl(register digit * p,register int len,register int sh)141 static void shl(register digit *p, register int len, register int sh)
142 {
143     register int i;
144 
145     for (i = 0; i < len; i++)
146         p[i] = LHALF(p[i] << sh) | (p[i + 1] >> (HALF_BITS - sh));
147     p[i] = LHALF(p[i] << sh);
148 }
149 
150 /*
151  * __qdivrem(u, v, rem) returns u/v and, optionally, sets *rem to u%v.
152  *
153  * We do this in base 2-sup-HALF_BITS, so that all intermediate products
154  * fit within unsigned long.  As a consequence, the maximum length dividend
155  * and divisor are 4 `digits' in this base (they are shorter if they have
156  * leading zeros).
157  */
__qdivrem(u64 uq,u64 vq,u64 * arq)158 u64 __qdivrem(u64 uq, u64 vq, u64 *arq)
159 {
160     union uu tmp;
161     digit *u, *v, *q;
162     register digit v1, v2;
163     unsigned long qhat, rhat, t;
164     int m, n, d, j, i;
165     digit uspace[5], vspace[5], qspace[5];
166 
167     /*
168      * Take care of special cases: divide by zero, and u < v.
169      */
170     if (vq == 0) {
171         /* divide by zero. */
172         static volatile const unsigned int zero = 0;
173 
174         tmp.ul[H] = tmp.ul[L] = 1 / zero;
175         if (arq)
176             *arq = uq;
177         return (tmp.q);
178     }
179     if (uq < vq) {
180         if (arq)
181             *arq = uq;
182         return (0);
183     }
184     u = &uspace[0];
185     v = &vspace[0];
186     q = &qspace[0];
187 
188     /*
189      * Break dividend and divisor into digits in base B, then
190      * count leading zeros to determine m and n.  When done, we
191      * will have:
192      * u = (u[1]u[2]...u[m+n]) sub B
193      * v = (v[1]v[2]...v[n]) sub B
194      * v[1] != 0
195      * 1 < n <= 4 (if n = 1, we use a different division algorithm)
196      * m >= 0 (otherwise u < v, which we already checked)
197      * m + n = 4
198      * and thus
199      * m = 4 - n <= 2
200      */
201     tmp.uq = uq;
202     u[0] = 0;
203     u[1] = HHALF(tmp.ul[H]);
204     u[2] = LHALF(tmp.ul[H]);
205     u[3] = HHALF(tmp.ul[L]);
206     u[4] = LHALF(tmp.ul[L]);
207     tmp.uq = vq;
208     v[1] = HHALF(tmp.ul[H]);
209     v[2] = LHALF(tmp.ul[H]);
210     v[3] = HHALF(tmp.ul[L]);
211     v[4] = LHALF(tmp.ul[L]);
212     for (n = 4; v[1] == 0; v++) {
213         if (--n == 1) {
214             unsigned long rbj; /* r*B+u[j] (not root boy jim) */
215             digit q1, q2, q3, q4;
216 
217             /*
218              * Change of plan, per exercise 16.
219              * r = 0;
220              * for j = 1..4:
221              *  q[j] = floor((r*B + u[j]) / v),
222              *  r = (r*B + u[j]) % v;
223              * We unroll this completely here.
224              */
225             t = v[2]; /* nonzero, by definition */
226             q1 = u[1] / t;
227             rbj = COMBINE(u[1] % t, u[2]);
228             q2 = rbj / t;
229             rbj = COMBINE(rbj % t, u[3]);
230             q3 = rbj / t;
231             rbj = COMBINE(rbj % t, u[4]);
232             q4 = rbj / t;
233             if (arq)
234                 *arq = rbj % t;
235             tmp.ul[H] = COMBINE(q1, q2);
236             tmp.ul[L] = COMBINE(q3, q4);
237             return (tmp.q);
238         }
239     }
240 
241     /*
242      * By adjusting q once we determine m, we can guarantee that
243      * there is a complete four-digit quotient at &qspace[1] when
244      * we finally stop.
245      */
246     for (m = 4 - n; u[1] == 0; u++)
247         m--;
248     for (i = 4 - m; --i >= 0;)
249         q[i] = 0;
250     q += 4 - m;
251 
252     /*
253      * Here we run Program D, translated from MIX to C and acquiring
254      * a few minor changes.
255      *
256      * D1: choose multiplier 1 << d to ensure v[1] >= B/2.
257      */
258     d = 0;
259     for (t = v[1]; t < B / 2; t <<= 1)
260         d++;
261     if (d > 0) {
262         shl(&u[0], m + n, d);  /* u <<= d */
263         shl(&v[1], n - 1, d);  /* v <<= d */
264     }
265     /*
266      * D2: j = 0.
267      */
268     j = 0;
269     v1 = v[1]; /* for D3 -- note that v[1..n] are constant */
270     v2 = v[2]; /* for D3 */
271     do {
272         register digit uj0, uj1, uj2;
273 
274         /*
275          * D3: Calculate qhat (\^q, in TeX notation).
276          * Let qhat = min((u[j]*B + u[j+1])/v[1], B-1), and
277          * let rhat = (u[j]*B + u[j+1]) mod v[1].
278          * While rhat < B and v[2]*qhat > rhat*B+u[j+2],
279          * decrement qhat and increase rhat correspondingly.
280          * Note that if rhat >= B, v[2]*qhat < rhat*B.
281          */
282         uj0 = u[j + 0]; /* for D3 only -- note that u[j+...] change */
283         uj1 = u[j + 1]; /* for D3 only */
284         uj2 = u[j + 2]; /* for D3 only */
285         if (uj0 == v1) {
286             qhat = B;
287             rhat = uj1;
288             goto qhat_too_big;
289         } else {
290             unsigned long nn = COMBINE(uj0, uj1);
291 
292             qhat = nn / v1;
293             rhat = nn % v1;
294         }
295         while (v2 * qhat > COMBINE(rhat, uj2)) {
296         qhat_too_big:
297             qhat--;
298             if ((rhat += v1) >= B)
299                 break;
300         }
301         /*
302          * D4: Multiply and subtract.
303          * The variable `t' holds any borrows across the loop.
304          * We split this up so that we do not require v[0] = 0,
305          * and to eliminate a final special case.
306          */
307         for (t = 0, i = n; i > 0; i--) {
308             t = u[i + j] - v[i] * qhat - t;
309             u[i + j] = LHALF(t);
310             t = (B - HHALF(t)) & (B - 1);
311         }
312         t = u[j] - t;
313         u[j] = LHALF(t);
314         /*
315          * D5: test remainder.
316          * There is a borrow if and only if HHALF(t) is nonzero;
317          * in that (rare) case, qhat was too large (by exactly 1).
318          * Fix it by adding v[1..n] to u[j..j+n].
319          */
320         if (HHALF(t)) {
321             qhat--;
322             for (t = 0, i = n; i > 0; i--) { /* D6: add back. */
323                 t += u[i + j] + v[i];
324                 u[i + j] = LHALF(t);
325                 t = HHALF(t);
326             }
327             u[j] = LHALF(u[j] + t);
328         }
329         q[j] = qhat;
330     } while (++j <= m);  /* D7: loop on j. */
331 
332     /*
333      * If caller wants the remainder, we have to calculate it as
334      * u[m..m+n] >> d (this is at most n digits and thus fits in
335      * u[m+1..m+n], but we may need more source digits).
336      */
337     if (arq) {
338         if (d) {
339             for (i = m + n; i > m; --i)
340                 u[i] = (u[i] >> d) |
341                     LHALF(u[i - 1] << (HALF_BITS - d));
342             u[i] = 0;
343         }
344         tmp.ul[H] = COMBINE(uspace[1], uspace[2]);
345         tmp.ul[L] = COMBINE(uspace[3], uspace[4]);
346         *arq = tmp.q;
347     }
348 
349     tmp.ul[H] = COMBINE(qspace[1], qspace[2]);
350     tmp.ul[L] = COMBINE(qspace[3], qspace[4]);
351     return (tmp.q);
352 }
353 
354 /*
355  * Divide two signed quads.
356  * Truncates towards zero, as required by C99.
357  */
__divdi3(s64 a,s64 b)358 s64 __divdi3(s64 a, s64 b)
359 {
360     u64 ua, ub, uq;
361     int neg = (a < 0) ^ (b < 0);
362     ua = (a < 0) ? -(u64)a : a;
363     ub = (b < 0) ? -(u64)b : b;
364     uq = __qdivrem(ua, ub, (u64 *)0);
365     return (neg ? -uq : uq);
366 }
367 
368 
369 /*
370  * Divide two unsigned quads.
371  */
__udivdi3(u64 a,u64 b)372 u64 __udivdi3(u64 a, u64 b)
373 {
374     return __qdivrem(a, b, (u64 *)0);
375 }
376 
377 /*
378  * Remainder of unsigned quad division
379  */
__umoddi3(u64 a,u64 b)380 u64 __umoddi3(u64 a, u64 b)
381 {
382     u64 rem;
383     __qdivrem(a, b, &rem);
384     return rem;
385 }
386 
387 /*
388  * Remainder of signed quad division.
389  * Truncates towards zero, as required by C99:
390  *  11 %  5 =  1
391  * -11 %  5 = -1
392  *  11 % -5 =  1
393  * -11 % -5 =  1
394  */
__moddi3(s64 a,s64 b)395 s64 __moddi3(s64 a, s64 b)
396 {
397     u64 ua, ub, urem;
398     int neg = (a < 0);
399     ua = neg ? -(u64)a : a;
400     ub = (b < 0) ? -(u64)b : b;
401     __qdivrem(ua, ub, &urem);
402     return (neg ? -urem : urem);
403 }
404 
405 /*
406  * Quotient and remainder of unsigned long long division
407  */
__ldivmod_helper(s64 a,s64 b,s64 * r)408 s64 __ldivmod_helper(s64 a, s64 b, s64 *r)
409 {
410     u64 ua, ub, rem, quot;
411 
412     ua = ABS(a);
413     ub = ABS(b);
414     quot = __qdivrem(ua, ub, &rem);
415     if ( a < 0 )
416         *r = -rem;
417     else
418         *r = rem;
419     if ( (a < 0) ^ (b < 0) )
420         return -quot;
421     else
422         return quot;
423 }
424 #endif /* BITS_PER_LONG == 32 */
425 
426 /* Compute with 96 bit intermediate result: (a*b)/c */
muldiv64(uint64_t a,uint32_t b,uint32_t c)427 uint64_t muldiv64(uint64_t a, uint32_t b, uint32_t c)
428 {
429 #ifdef CONFIG_X86
430     asm ( "mul %%rdx; div %%rcx" : "=a" (a) : "0" (a), "d" (b), "c" (c) );
431     return a;
432 #else
433     union {
434         uint64_t ll;
435         struct {
436 #ifdef WORDS_BIGENDIAN
437             uint32_t high, low;
438 #else
439             uint32_t low, high;
440 #endif
441         } l;
442     } u, res;
443     uint64_t rl, rh;
444 
445     u.ll = a;
446     rl = (uint64_t)u.l.low * (uint64_t)b;
447     rh = (uint64_t)u.l.high * (uint64_t)b;
448     rh += (rl >> 32);
449     res.l.high = rh / c;
450     res.l.low = (((rh % c) << 32) + (rl & 0xffffffff)) / c;
451     return res.ll;
452 #endif
453 }
454 
parse_size_and_unit(const char * s,const char ** ps)455 unsigned long long parse_size_and_unit(const char *s, const char **ps)
456 {
457     unsigned long long ret;
458     const char *s1;
459 
460     ret = simple_strtoull(s, &s1, 0);
461 
462     switch ( *s1 )
463     {
464     case 'T': case 't':
465         ret <<= 10;
466         /* fallthrough */
467     case 'G': case 'g':
468         ret <<= 10;
469         /* fallthrough */
470     case 'M': case 'm':
471         ret <<= 10;
472         /* fallthrough */
473     case 'K': case 'k':
474         ret <<= 10;
475         /* fallthrough */
476     case 'B': case 'b':
477         s1++;
478         break;
479     default:
480         ret <<= 10; /* default to kB */
481         break;
482     }
483 
484     if ( ps != NULL )
485         *ps = s1;
486 
487     return ret;
488 }
489 
490 typedef void (*ctor_func_t)(void);
491 extern const ctor_func_t __ctors_start[], __ctors_end[];
492 
init_constructors(void)493 void __init init_constructors(void)
494 {
495     const ctor_func_t *f;
496     for ( f = __ctors_start; f < __ctors_end; ++f )
497         (*f)();
498 
499     /* Putting this here seems as good (or bad) as any other place. */
500     BUILD_BUG_ON(sizeof(size_t) != sizeof(ssize_t));
501 }
502 
503 /*
504  * Local variables:
505  * mode: C
506  * c-file-style: "BSD"
507  * c-basic-offset: 4
508  * tab-width: 4
509  * indent-tabs-mode: nil
510  * End:
511  */
512