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1da177e4 LT |
1 | /* |
2 | * ECC algorithm for M-systems disk on chip. We use the excellent Reed | |
3 | * Solmon code of Phil Karn (karn@ka9q.ampr.org) available under the | |
4 | * GNU GPL License. The rest is simply to convert the disk on chip | |
5 | * syndrom into a standard syndom. | |
6 | * | |
7 | * Author: Fabrice Bellard (fabrice.bellard@netgem.com) | |
8 | * Copyright (C) 2000 Netgem S.A. | |
9 | * | |
10 | * $Id: docecc.c,v 1.5 2003/05/21 15:15:06 dwmw2 Exp $ | |
11 | * | |
12 | * This program is free software; you can redistribute it and/or modify | |
13 | * it under the terms of the GNU General Public License as published by | |
14 | * the Free Software Foundation; either version 2 of the License, or | |
15 | * (at your option) any later version. | |
16 | * | |
17 | * This program is distributed in the hope that it will be useful, | |
18 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
20 | * GNU General Public License for more details. | |
21 | * | |
22 | * You should have received a copy of the GNU General Public License | |
23 | * along with this program; if not, write to the Free Software | |
24 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
25 | */ | |
26 | #include <linux/kernel.h> | |
27 | #include <linux/module.h> | |
28 | #include <asm/errno.h> | |
29 | #include <asm/io.h> | |
30 | #include <asm/uaccess.h> | |
31 | #include <linux/miscdevice.h> | |
32 | #include <linux/pci.h> | |
33 | #include <linux/delay.h> | |
34 | #include <linux/slab.h> | |
35 | #include <linux/sched.h> | |
36 | #include <linux/init.h> | |
37 | #include <linux/types.h> | |
38 | ||
39 | #include <linux/mtd/compatmac.h> /* for min() in older kernels */ | |
40 | #include <linux/mtd/mtd.h> | |
41 | #include <linux/mtd/doc2000.h> | |
42 | ||
44456d37 | 43 | #define DEBUG 0 |
1da177e4 LT |
44 | /* need to undef it (from asm/termbits.h) */ |
45 | #undef B0 | |
46 | ||
47 | #define MM 10 /* Symbol size in bits */ | |
48 | #define KK (1023-4) /* Number of data symbols per block */ | |
49 | #define B0 510 /* First root of generator polynomial, alpha form */ | |
50 | #define PRIM 1 /* power of alpha used to generate roots of generator poly */ | |
51 | #define NN ((1 << MM) - 1) | |
52 | ||
53 | typedef unsigned short dtype; | |
54 | ||
55 | /* 1+x^3+x^10 */ | |
56 | static const int Pp[MM+1] = { 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1 }; | |
57 | ||
58 | /* This defines the type used to store an element of the Galois Field | |
59 | * used by the code. Make sure this is something larger than a char if | |
60 | * if anything larger than GF(256) is used. | |
61 | * | |
62 | * Note: unsigned char will work up to GF(256) but int seems to run | |
63 | * faster on the Pentium. | |
64 | */ | |
65 | typedef int gf; | |
66 | ||
67 | /* No legal value in index form represents zero, so | |
68 | * we need a special value for this purpose | |
69 | */ | |
70 | #define A0 (NN) | |
71 | ||
72 | /* Compute x % NN, where NN is 2**MM - 1, | |
73 | * without a slow divide | |
74 | */ | |
75 | static inline gf | |
76 | modnn(int x) | |
77 | { | |
78 | while (x >= NN) { | |
79 | x -= NN; | |
80 | x = (x >> MM) + (x & NN); | |
81 | } | |
82 | return x; | |
83 | } | |
84 | ||
85 | #define CLEAR(a,n) {\ | |
86 | int ci;\ | |
87 | for(ci=(n)-1;ci >=0;ci--)\ | |
88 | (a)[ci] = 0;\ | |
89 | } | |
90 | ||
91 | #define COPY(a,b,n) {\ | |
92 | int ci;\ | |
93 | for(ci=(n)-1;ci >=0;ci--)\ | |
94 | (a)[ci] = (b)[ci];\ | |
95 | } | |
96 | ||
97 | #define COPYDOWN(a,b,n) {\ | |
98 | int ci;\ | |
99 | for(ci=(n)-1;ci >=0;ci--)\ | |
100 | (a)[ci] = (b)[ci];\ | |
101 | } | |
102 | ||
103 | #define Ldec 1 | |
104 | ||
105 | /* generate GF(2**m) from the irreducible polynomial p(X) in Pp[0]..Pp[m] | |
106 | lookup tables: index->polynomial form alpha_to[] contains j=alpha**i; | |
107 | polynomial form -> index form index_of[j=alpha**i] = i | |
108 | alpha=2 is the primitive element of GF(2**m) | |
109 | HARI's COMMENT: (4/13/94) alpha_to[] can be used as follows: | |
110 | Let @ represent the primitive element commonly called "alpha" that | |
111 | is the root of the primitive polynomial p(x). Then in GF(2^m), for any | |
112 | 0 <= i <= 2^m-2, | |
113 | @^i = a(0) + a(1) @ + a(2) @^2 + ... + a(m-1) @^(m-1) | |
114 | where the binary vector (a(0),a(1),a(2),...,a(m-1)) is the representation | |
115 | of the integer "alpha_to[i]" with a(0) being the LSB and a(m-1) the MSB. Thus for | |
116 | example the polynomial representation of @^5 would be given by the binary | |
117 | representation of the integer "alpha_to[5]". | |
118 | Similarily, index_of[] can be used as follows: | |
119 | As above, let @ represent the primitive element of GF(2^m) that is | |
120 | the root of the primitive polynomial p(x). In order to find the power | |
121 | of @ (alpha) that has the polynomial representation | |
122 | a(0) + a(1) @ + a(2) @^2 + ... + a(m-1) @^(m-1) | |
123 | we consider the integer "i" whose binary representation with a(0) being LSB | |
124 | and a(m-1) MSB is (a(0),a(1),...,a(m-1)) and locate the entry | |
125 | "index_of[i]". Now, @^index_of[i] is that element whose polynomial | |
126 | representation is (a(0),a(1),a(2),...,a(m-1)). | |
127 | NOTE: | |
128 | The element alpha_to[2^m-1] = 0 always signifying that the | |
129 | representation of "@^infinity" = 0 is (0,0,0,...,0). | |
130 | Similarily, the element index_of[0] = A0 always signifying | |
131 | that the power of alpha which has the polynomial representation | |
132 | (0,0,...,0) is "infinity". | |
133 | ||
134 | */ | |
135 | ||
136 | static void | |
137 | generate_gf(dtype Alpha_to[NN + 1], dtype Index_of[NN + 1]) | |
138 | { | |
139 | register int i, mask; | |
140 | ||
141 | mask = 1; | |
142 | Alpha_to[MM] = 0; | |
143 | for (i = 0; i < MM; i++) { | |
144 | Alpha_to[i] = mask; | |
145 | Index_of[Alpha_to[i]] = i; | |
146 | /* If Pp[i] == 1 then, term @^i occurs in poly-repr of @^MM */ | |
147 | if (Pp[i] != 0) | |
148 | Alpha_to[MM] ^= mask; /* Bit-wise EXOR operation */ | |
149 | mask <<= 1; /* single left-shift */ | |
150 | } | |
151 | Index_of[Alpha_to[MM]] = MM; | |
152 | /* | |
153 | * Have obtained poly-repr of @^MM. Poly-repr of @^(i+1) is given by | |
154 | * poly-repr of @^i shifted left one-bit and accounting for any @^MM | |
155 | * term that may occur when poly-repr of @^i is shifted. | |
156 | */ | |
157 | mask >>= 1; | |
158 | for (i = MM + 1; i < NN; i++) { | |
159 | if (Alpha_to[i - 1] >= mask) | |
160 | Alpha_to[i] = Alpha_to[MM] ^ ((Alpha_to[i - 1] ^ mask) << 1); | |
161 | else | |
162 | Alpha_to[i] = Alpha_to[i - 1] << 1; | |
163 | Index_of[Alpha_to[i]] = i; | |
164 | } | |
165 | Index_of[0] = A0; | |
166 | Alpha_to[NN] = 0; | |
167 | } | |
168 | ||
169 | /* | |
170 | * Performs ERRORS+ERASURES decoding of RS codes. bb[] is the content | |
171 | * of the feedback shift register after having processed the data and | |
172 | * the ECC. | |
173 | * | |
174 | * Return number of symbols corrected, or -1 if codeword is illegal | |
175 | * or uncorrectable. If eras_pos is non-null, the detected error locations | |
176 | * are written back. NOTE! This array must be at least NN-KK elements long. | |
177 | * The corrected data are written in eras_val[]. They must be xor with the data | |
178 | * to retrieve the correct data : data[erase_pos[i]] ^= erase_val[i] . | |
179 | * | |
180 | * First "no_eras" erasures are declared by the calling program. Then, the | |
181 | * maximum # of errors correctable is t_after_eras = floor((NN-KK-no_eras)/2). | |
182 | * If the number of channel errors is not greater than "t_after_eras" the | |
183 | * transmitted codeword will be recovered. Details of algorithm can be found | |
184 | * in R. Blahut's "Theory ... of Error-Correcting Codes". | |
185 | ||
186 | * Warning: the eras_pos[] array must not contain duplicate entries; decoder failure | |
187 | * will result. The decoder *could* check for this condition, but it would involve | |
188 | * extra time on every decoding operation. | |
189 | * */ | |
190 | static int | |
191 | eras_dec_rs(dtype Alpha_to[NN + 1], dtype Index_of[NN + 1], | |
192 | gf bb[NN - KK + 1], gf eras_val[NN-KK], int eras_pos[NN-KK], | |
193 | int no_eras) | |
194 | { | |
195 | int deg_lambda, el, deg_omega; | |
196 | int i, j, r,k; | |
197 | gf u,q,tmp,num1,num2,den,discr_r; | |
198 | gf lambda[NN-KK + 1], s[NN-KK + 1]; /* Err+Eras Locator poly | |
199 | * and syndrome poly */ | |
200 | gf b[NN-KK + 1], t[NN-KK + 1], omega[NN-KK + 1]; | |
201 | gf root[NN-KK], reg[NN-KK + 1], loc[NN-KK]; | |
202 | int syn_error, count; | |
203 | ||
204 | syn_error = 0; | |
205 | for(i=0;i<NN-KK;i++) | |
206 | syn_error |= bb[i]; | |
207 | ||
208 | if (!syn_error) { | |
209 | /* if remainder is zero, data[] is a codeword and there are no | |
210 | * errors to correct. So return data[] unmodified | |
211 | */ | |
212 | count = 0; | |
213 | goto finish; | |
214 | } | |
215 | ||
216 | for(i=1;i<=NN-KK;i++){ | |
217 | s[i] = bb[0]; | |
218 | } | |
219 | for(j=1;j<NN-KK;j++){ | |
220 | if(bb[j] == 0) | |
221 | continue; | |
222 | tmp = Index_of[bb[j]]; | |
223 | ||
224 | for(i=1;i<=NN-KK;i++) | |
225 | s[i] ^= Alpha_to[modnn(tmp + (B0+i-1)*PRIM*j)]; | |
226 | } | |
227 | ||
228 | /* undo the feedback register implicit multiplication and convert | |
229 | syndromes to index form */ | |
230 | ||
231 | for(i=1;i<=NN-KK;i++) { | |
232 | tmp = Index_of[s[i]]; | |
233 | if (tmp != A0) | |
234 | tmp = modnn(tmp + 2 * KK * (B0+i-1)*PRIM); | |
235 | s[i] = tmp; | |
236 | } | |
237 | ||
238 | CLEAR(&lambda[1],NN-KK); | |
239 | lambda[0] = 1; | |
240 | ||
241 | if (no_eras > 0) { | |
242 | /* Init lambda to be the erasure locator polynomial */ | |
243 | lambda[1] = Alpha_to[modnn(PRIM * eras_pos[0])]; | |
244 | for (i = 1; i < no_eras; i++) { | |
245 | u = modnn(PRIM*eras_pos[i]); | |
246 | for (j = i+1; j > 0; j--) { | |
247 | tmp = Index_of[lambda[j - 1]]; | |
248 | if(tmp != A0) | |
249 | lambda[j] ^= Alpha_to[modnn(u + tmp)]; | |
250 | } | |
251 | } | |
252 | #if DEBUG >= 1 | |
253 | /* Test code that verifies the erasure locator polynomial just constructed | |
254 | Needed only for decoder debugging. */ | |
255 | ||
256 | /* find roots of the erasure location polynomial */ | |
257 | for(i=1;i<=no_eras;i++) | |
258 | reg[i] = Index_of[lambda[i]]; | |
259 | count = 0; | |
260 | for (i = 1,k=NN-Ldec; i <= NN; i++,k = modnn(NN+k-Ldec)) { | |
261 | q = 1; | |
262 | for (j = 1; j <= no_eras; j++) | |
263 | if (reg[j] != A0) { | |
264 | reg[j] = modnn(reg[j] + j); | |
265 | q ^= Alpha_to[reg[j]]; | |
266 | } | |
267 | if (q != 0) | |
268 | continue; | |
269 | /* store root and error location number indices */ | |
270 | root[count] = i; | |
271 | loc[count] = k; | |
272 | count++; | |
273 | } | |
274 | if (count != no_eras) { | |
275 | printf("\n lambda(x) is WRONG\n"); | |
276 | count = -1; | |
277 | goto finish; | |
278 | } | |
279 | #if DEBUG >= 2 | |
280 | printf("\n Erasure positions as determined by roots of Eras Loc Poly:\n"); | |
281 | for (i = 0; i < count; i++) | |
282 | printf("%d ", loc[i]); | |
283 | printf("\n"); | |
284 | #endif | |
285 | #endif | |
286 | } | |
287 | for(i=0;i<NN-KK+1;i++) | |
288 | b[i] = Index_of[lambda[i]]; | |
289 | ||
290 | /* | |
291 | * Begin Berlekamp-Massey algorithm to determine error+erasure | |
292 | * locator polynomial | |
293 | */ | |
294 | r = no_eras; | |
295 | el = no_eras; | |
296 | while (++r <= NN-KK) { /* r is the step number */ | |
297 | /* Compute discrepancy at the r-th step in poly-form */ | |
298 | discr_r = 0; | |
299 | for (i = 0; i < r; i++){ | |
300 | if ((lambda[i] != 0) && (s[r - i] != A0)) { | |
301 | discr_r ^= Alpha_to[modnn(Index_of[lambda[i]] + s[r - i])]; | |
302 | } | |
303 | } | |
304 | discr_r = Index_of[discr_r]; /* Index form */ | |
305 | if (discr_r == A0) { | |
306 | /* 2 lines below: B(x) <-- x*B(x) */ | |
307 | COPYDOWN(&b[1],b,NN-KK); | |
308 | b[0] = A0; | |
309 | } else { | |
310 | /* 7 lines below: T(x) <-- lambda(x) - discr_r*x*b(x) */ | |
311 | t[0] = lambda[0]; | |
312 | for (i = 0 ; i < NN-KK; i++) { | |
313 | if(b[i] != A0) | |
314 | t[i+1] = lambda[i+1] ^ Alpha_to[modnn(discr_r + b[i])]; | |
315 | else | |
316 | t[i+1] = lambda[i+1]; | |
317 | } | |
318 | if (2 * el <= r + no_eras - 1) { | |
319 | el = r + no_eras - el; | |
320 | /* | |
321 | * 2 lines below: B(x) <-- inv(discr_r) * | |
322 | * lambda(x) | |
323 | */ | |
324 | for (i = 0; i <= NN-KK; i++) | |
325 | b[i] = (lambda[i] == 0) ? A0 : modnn(Index_of[lambda[i]] - discr_r + NN); | |
326 | } else { | |
327 | /* 2 lines below: B(x) <-- x*B(x) */ | |
328 | COPYDOWN(&b[1],b,NN-KK); | |
329 | b[0] = A0; | |
330 | } | |
331 | COPY(lambda,t,NN-KK+1); | |
332 | } | |
333 | } | |
334 | ||
335 | /* Convert lambda to index form and compute deg(lambda(x)) */ | |
336 | deg_lambda = 0; | |
337 | for(i=0;i<NN-KK+1;i++){ | |
338 | lambda[i] = Index_of[lambda[i]]; | |
339 | if(lambda[i] != A0) | |
340 | deg_lambda = i; | |
341 | } | |
342 | /* | |
343 | * Find roots of the error+erasure locator polynomial by Chien | |
344 | * Search | |
345 | */ | |
346 | COPY(®[1],&lambda[1],NN-KK); | |
347 | count = 0; /* Number of roots of lambda(x) */ | |
348 | for (i = 1,k=NN-Ldec; i <= NN; i++,k = modnn(NN+k-Ldec)) { | |
349 | q = 1; | |
350 | for (j = deg_lambda; j > 0; j--){ | |
351 | if (reg[j] != A0) { | |
352 | reg[j] = modnn(reg[j] + j); | |
353 | q ^= Alpha_to[reg[j]]; | |
354 | } | |
355 | } | |
356 | if (q != 0) | |
357 | continue; | |
358 | /* store root (index-form) and error location number */ | |
359 | root[count] = i; | |
360 | loc[count] = k; | |
361 | /* If we've already found max possible roots, | |
362 | * abort the search to save time | |
363 | */ | |
364 | if(++count == deg_lambda) | |
365 | break; | |
366 | } | |
367 | if (deg_lambda != count) { | |
368 | /* | |
369 | * deg(lambda) unequal to number of roots => uncorrectable | |
370 | * error detected | |
371 | */ | |
372 | count = -1; | |
373 | goto finish; | |
374 | } | |
375 | /* | |
376 | * Compute err+eras evaluator poly omega(x) = s(x)*lambda(x) (modulo | |
377 | * x**(NN-KK)). in index form. Also find deg(omega). | |
378 | */ | |
379 | deg_omega = 0; | |
380 | for (i = 0; i < NN-KK;i++){ | |
381 | tmp = 0; | |
382 | j = (deg_lambda < i) ? deg_lambda : i; | |
383 | for(;j >= 0; j--){ | |
384 | if ((s[i + 1 - j] != A0) && (lambda[j] != A0)) | |
385 | tmp ^= Alpha_to[modnn(s[i + 1 - j] + lambda[j])]; | |
386 | } | |
387 | if(tmp != 0) | |
388 | deg_omega = i; | |
389 | omega[i] = Index_of[tmp]; | |
390 | } | |
391 | omega[NN-KK] = A0; | |
392 | ||
393 | /* | |
394 | * Compute error values in poly-form. num1 = omega(inv(X(l))), num2 = | |
395 | * inv(X(l))**(B0-1) and den = lambda_pr(inv(X(l))) all in poly-form | |
396 | */ | |
397 | for (j = count-1; j >=0; j--) { | |
398 | num1 = 0; | |
399 | for (i = deg_omega; i >= 0; i--) { | |
400 | if (omega[i] != A0) | |
401 | num1 ^= Alpha_to[modnn(omega[i] + i * root[j])]; | |
402 | } | |
403 | num2 = Alpha_to[modnn(root[j] * (B0 - 1) + NN)]; | |
404 | den = 0; | |
405 | ||
406 | /* lambda[i+1] for i even is the formal derivative lambda_pr of lambda[i] */ | |
407 | for (i = min(deg_lambda,NN-KK-1) & ~1; i >= 0; i -=2) { | |
408 | if(lambda[i+1] != A0) | |
409 | den ^= Alpha_to[modnn(lambda[i+1] + i * root[j])]; | |
410 | } | |
411 | if (den == 0) { | |
412 | #if DEBUG >= 1 | |
413 | printf("\n ERROR: denominator = 0\n"); | |
414 | #endif | |
415 | /* Convert to dual- basis */ | |
416 | count = -1; | |
417 | goto finish; | |
418 | } | |
419 | /* Apply error to data */ | |
420 | if (num1 != 0) { | |
421 | eras_val[j] = Alpha_to[modnn(Index_of[num1] + Index_of[num2] + NN - Index_of[den])]; | |
422 | } else { | |
423 | eras_val[j] = 0; | |
424 | } | |
425 | } | |
426 | finish: | |
427 | for(i=0;i<count;i++) | |
428 | eras_pos[i] = loc[i]; | |
429 | return count; | |
430 | } | |
431 | ||
432 | /***************************************************************************/ | |
433 | /* The DOC specific code begins here */ | |
434 | ||
435 | #define SECTOR_SIZE 512 | |
436 | /* The sector bytes are packed into NB_DATA MM bits words */ | |
437 | #define NB_DATA (((SECTOR_SIZE + 1) * 8 + 6) / MM) | |
438 | ||
439 | /* | |
440 | * Correct the errors in 'sector[]' by using 'ecc1[]' which is the | |
441 | * content of the feedback shift register applyied to the sector and | |
442 | * the ECC. Return the number of errors corrected (and correct them in | |
443 | * sector), or -1 if error | |
444 | */ | |
445 | int doc_decode_ecc(unsigned char sector[SECTOR_SIZE], unsigned char ecc1[6]) | |
446 | { | |
447 | int parity, i, nb_errors; | |
448 | gf bb[NN - KK + 1]; | |
449 | gf error_val[NN-KK]; | |
450 | int error_pos[NN-KK], pos, bitpos, index, val; | |
451 | dtype *Alpha_to, *Index_of; | |
452 | ||
453 | /* init log and exp tables here to save memory. However, it is slower */ | |
454 | Alpha_to = kmalloc((NN + 1) * sizeof(dtype), GFP_KERNEL); | |
455 | if (!Alpha_to) | |
456 | return -1; | |
457 | ||
458 | Index_of = kmalloc((NN + 1) * sizeof(dtype), GFP_KERNEL); | |
459 | if (!Index_of) { | |
460 | kfree(Alpha_to); | |
461 | return -1; | |
462 | } | |
463 | ||
464 | generate_gf(Alpha_to, Index_of); | |
465 | ||
466 | parity = ecc1[1]; | |
467 | ||
468 | bb[0] = (ecc1[4] & 0xff) | ((ecc1[5] & 0x03) << 8); | |
469 | bb[1] = ((ecc1[5] & 0xfc) >> 2) | ((ecc1[2] & 0x0f) << 6); | |
470 | bb[2] = ((ecc1[2] & 0xf0) >> 4) | ((ecc1[3] & 0x3f) << 4); | |
471 | bb[3] = ((ecc1[3] & 0xc0) >> 6) | ((ecc1[0] & 0xff) << 2); | |
472 | ||
473 | nb_errors = eras_dec_rs(Alpha_to, Index_of, bb, | |
474 | error_val, error_pos, 0); | |
475 | if (nb_errors <= 0) | |
476 | goto the_end; | |
477 | ||
478 | /* correct the errors */ | |
479 | for(i=0;i<nb_errors;i++) { | |
480 | pos = error_pos[i]; | |
481 | if (pos >= NB_DATA && pos < KK) { | |
482 | nb_errors = -1; | |
483 | goto the_end; | |
484 | } | |
485 | if (pos < NB_DATA) { | |
486 | /* extract bit position (MSB first) */ | |
487 | pos = 10 * (NB_DATA - 1 - pos) - 6; | |
488 | /* now correct the following 10 bits. At most two bytes | |
489 | can be modified since pos is even */ | |
490 | index = (pos >> 3) ^ 1; | |
491 | bitpos = pos & 7; | |
492 | if ((index >= 0 && index < SECTOR_SIZE) || | |
493 | index == (SECTOR_SIZE + 1)) { | |
494 | val = error_val[i] >> (2 + bitpos); | |
495 | parity ^= val; | |
496 | if (index < SECTOR_SIZE) | |
497 | sector[index] ^= val; | |
498 | } | |
499 | index = ((pos >> 3) + 1) ^ 1; | |
500 | bitpos = (bitpos + 10) & 7; | |
501 | if (bitpos == 0) | |
502 | bitpos = 8; | |
503 | if ((index >= 0 && index < SECTOR_SIZE) || | |
504 | index == (SECTOR_SIZE + 1)) { | |
505 | val = error_val[i] << (8 - bitpos); | |
506 | parity ^= val; | |
507 | if (index < SECTOR_SIZE) | |
508 | sector[index] ^= val; | |
509 | } | |
510 | } | |
511 | } | |
512 | ||
513 | /* use parity to test extra errors */ | |
514 | if ((parity & 0xff) != 0) | |
515 | nb_errors = -1; | |
516 | ||
517 | the_end: | |
518 | kfree(Alpha_to); | |
519 | kfree(Index_of); | |
520 | return nb_errors; | |
521 | } | |
522 | ||
523 | EXPORT_SYMBOL_GPL(doc_decode_ecc); | |
524 | ||
525 | MODULE_LICENSE("GPL"); | |
526 | MODULE_AUTHOR("Fabrice Bellard <fabrice.bellard@netgem.com>"); | |
527 | MODULE_DESCRIPTION("ECC code for correcting errors detected by DiskOnChip 2000 and Millennium ECC hardware"); |