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0a82a623 DW |
1 | /* |
2 | * Asynchronous RAID-6 recovery calculations ASYNC_TX API. | |
3 | * Copyright(c) 2009 Intel Corporation | |
4 | * | |
5 | * based on raid6recov.c: | |
6 | * Copyright 2002 H. Peter Anvin | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or modify it | |
9 | * under the terms of the GNU General Public License as published by the Free | |
10 | * Software Foundation; either version 2 of the License, or (at your option) | |
11 | * any later version. | |
12 | * | |
13 | * This program is distributed in the hope that it will be useful, but WITHOUT | |
14 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
15 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
16 | * more details. | |
17 | * | |
18 | * You should have received a copy of the GNU General Public License along with | |
19 | * this program; if not, write to the Free Software Foundation, Inc., 51 | |
20 | * Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. | |
21 | * | |
22 | */ | |
23 | #include <linux/kernel.h> | |
24 | #include <linux/interrupt.h> | |
25 | #include <linux/dma-mapping.h> | |
26 | #include <linux/raid/pq.h> | |
27 | #include <linux/async_tx.h> | |
28 | ||
29 | static struct dma_async_tx_descriptor * | |
30 | async_sum_product(struct page *dest, struct page **srcs, unsigned char *coef, | |
31 | size_t len, struct async_submit_ctl *submit) | |
32 | { | |
33 | struct dma_chan *chan = async_tx_find_channel(submit, DMA_PQ, | |
34 | &dest, 1, srcs, 2, len); | |
35 | struct dma_device *dma = chan ? chan->device : NULL; | |
36 | const u8 *amul, *bmul; | |
37 | u8 ax, bx; | |
38 | u8 *a, *b, *c; | |
39 | ||
40 | if (dma) { | |
41 | dma_addr_t dma_dest[2]; | |
42 | dma_addr_t dma_src[2]; | |
43 | struct device *dev = dma->dev; | |
44 | struct dma_async_tx_descriptor *tx; | |
45 | enum dma_ctrl_flags dma_flags = DMA_PREP_PQ_DISABLE_P; | |
46 | ||
0403e382 DW |
47 | if (submit->flags & ASYNC_TX_FENCE) |
48 | dma_flags |= DMA_PREP_FENCE; | |
0a82a623 DW |
49 | dma_dest[1] = dma_map_page(dev, dest, 0, len, DMA_BIDIRECTIONAL); |
50 | dma_src[0] = dma_map_page(dev, srcs[0], 0, len, DMA_TO_DEVICE); | |
51 | dma_src[1] = dma_map_page(dev, srcs[1], 0, len, DMA_TO_DEVICE); | |
52 | tx = dma->device_prep_dma_pq(chan, dma_dest, dma_src, 2, coef, | |
53 | len, dma_flags); | |
54 | if (tx) { | |
55 | async_tx_submit(chan, tx, submit); | |
56 | return tx; | |
57 | } | |
1f6672d4 DW |
58 | |
59 | /* could not get a descriptor, unmap and fall through to | |
60 | * the synchronous path | |
61 | */ | |
62 | dma_unmap_page(dev, dma_dest[1], len, DMA_BIDIRECTIONAL); | |
63 | dma_unmap_page(dev, dma_src[0], len, DMA_TO_DEVICE); | |
64 | dma_unmap_page(dev, dma_src[1], len, DMA_TO_DEVICE); | |
0a82a623 DW |
65 | } |
66 | ||
67 | /* run the operation synchronously */ | |
68 | async_tx_quiesce(&submit->depend_tx); | |
69 | amul = raid6_gfmul[coef[0]]; | |
70 | bmul = raid6_gfmul[coef[1]]; | |
71 | a = page_address(srcs[0]); | |
72 | b = page_address(srcs[1]); | |
73 | c = page_address(dest); | |
74 | ||
75 | while (len--) { | |
76 | ax = amul[*a++]; | |
77 | bx = bmul[*b++]; | |
78 | *c++ = ax ^ bx; | |
79 | } | |
80 | ||
81 | return NULL; | |
82 | } | |
83 | ||
84 | static struct dma_async_tx_descriptor * | |
85 | async_mult(struct page *dest, struct page *src, u8 coef, size_t len, | |
86 | struct async_submit_ctl *submit) | |
87 | { | |
88 | struct dma_chan *chan = async_tx_find_channel(submit, DMA_PQ, | |
89 | &dest, 1, &src, 1, len); | |
90 | struct dma_device *dma = chan ? chan->device : NULL; | |
91 | const u8 *qmul; /* Q multiplier table */ | |
92 | u8 *d, *s; | |
93 | ||
94 | if (dma) { | |
95 | dma_addr_t dma_dest[2]; | |
96 | dma_addr_t dma_src[1]; | |
97 | struct device *dev = dma->dev; | |
98 | struct dma_async_tx_descriptor *tx; | |
99 | enum dma_ctrl_flags dma_flags = DMA_PREP_PQ_DISABLE_P; | |
100 | ||
0403e382 DW |
101 | if (submit->flags & ASYNC_TX_FENCE) |
102 | dma_flags |= DMA_PREP_FENCE; | |
0a82a623 DW |
103 | dma_dest[1] = dma_map_page(dev, dest, 0, len, DMA_BIDIRECTIONAL); |
104 | dma_src[0] = dma_map_page(dev, src, 0, len, DMA_TO_DEVICE); | |
105 | tx = dma->device_prep_dma_pq(chan, dma_dest, dma_src, 1, &coef, | |
106 | len, dma_flags); | |
107 | if (tx) { | |
108 | async_tx_submit(chan, tx, submit); | |
109 | return tx; | |
110 | } | |
1f6672d4 DW |
111 | |
112 | /* could not get a descriptor, unmap and fall through to | |
113 | * the synchronous path | |
114 | */ | |
115 | dma_unmap_page(dev, dma_dest[1], len, DMA_BIDIRECTIONAL); | |
116 | dma_unmap_page(dev, dma_src[0], len, DMA_TO_DEVICE); | |
0a82a623 DW |
117 | } |
118 | ||
119 | /* no channel available, or failed to allocate a descriptor, so | |
120 | * perform the operation synchronously | |
121 | */ | |
122 | async_tx_quiesce(&submit->depend_tx); | |
123 | qmul = raid6_gfmul[coef]; | |
124 | d = page_address(dest); | |
125 | s = page_address(src); | |
126 | ||
127 | while (len--) | |
128 | *d++ = qmul[*s++]; | |
129 | ||
130 | return NULL; | |
131 | } | |
132 | ||
133 | static struct dma_async_tx_descriptor * | |
da17bf43 DW |
134 | __2data_recov_4(int disks, size_t bytes, int faila, int failb, |
135 | struct page **blocks, struct async_submit_ctl *submit) | |
0a82a623 DW |
136 | { |
137 | struct dma_async_tx_descriptor *tx = NULL; | |
138 | struct page *p, *q, *a, *b; | |
139 | struct page *srcs[2]; | |
140 | unsigned char coef[2]; | |
141 | enum async_tx_flags flags = submit->flags; | |
142 | dma_async_tx_callback cb_fn = submit->cb_fn; | |
143 | void *cb_param = submit->cb_param; | |
144 | void *scribble = submit->scribble; | |
145 | ||
da17bf43 DW |
146 | p = blocks[disks-2]; |
147 | q = blocks[disks-1]; | |
0a82a623 DW |
148 | |
149 | a = blocks[faila]; | |
150 | b = blocks[failb]; | |
151 | ||
152 | /* in the 4 disk case P + Pxy == P and Q + Qxy == Q */ | |
153 | /* Dx = A*(P+Pxy) + B*(Q+Qxy) */ | |
154 | srcs[0] = p; | |
155 | srcs[1] = q; | |
156 | coef[0] = raid6_gfexi[failb-faila]; | |
157 | coef[1] = raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]]; | |
0403e382 | 158 | init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); |
0a82a623 DW |
159 | tx = async_sum_product(b, srcs, coef, bytes, submit); |
160 | ||
161 | /* Dy = P+Pxy+Dx */ | |
162 | srcs[0] = p; | |
163 | srcs[1] = b; | |
164 | init_async_submit(submit, flags | ASYNC_TX_XOR_ZERO_DST, tx, cb_fn, | |
165 | cb_param, scribble); | |
166 | tx = async_xor(a, srcs, 0, 2, bytes, submit); | |
167 | ||
168 | return tx; | |
169 | ||
170 | } | |
171 | ||
172 | static struct dma_async_tx_descriptor * | |
da17bf43 DW |
173 | __2data_recov_5(int disks, size_t bytes, int faila, int failb, |
174 | struct page **blocks, struct async_submit_ctl *submit) | |
0a82a623 DW |
175 | { |
176 | struct dma_async_tx_descriptor *tx = NULL; | |
177 | struct page *p, *q, *g, *dp, *dq; | |
178 | struct page *srcs[2]; | |
179 | unsigned char coef[2]; | |
180 | enum async_tx_flags flags = submit->flags; | |
181 | dma_async_tx_callback cb_fn = submit->cb_fn; | |
182 | void *cb_param = submit->cb_param; | |
183 | void *scribble = submit->scribble; | |
da17bf43 | 184 | int good_srcs, good, i; |
0a82a623 | 185 | |
da17bf43 DW |
186 | good_srcs = 0; |
187 | good = -1; | |
188 | for (i = 0; i < disks-2; i++) { | |
189 | if (blocks[i] == NULL) | |
190 | continue; | |
0a82a623 DW |
191 | if (i == faila || i == failb) |
192 | continue; | |
da17bf43 DW |
193 | good = i; |
194 | good_srcs++; | |
0a82a623 | 195 | } |
da17bf43 | 196 | BUG_ON(good_srcs > 1); |
0a82a623 | 197 | |
da17bf43 DW |
198 | p = blocks[disks-2]; |
199 | q = blocks[disks-1]; | |
0a82a623 DW |
200 | g = blocks[good]; |
201 | ||
202 | /* Compute syndrome with zero for the missing data pages | |
203 | * Use the dead data pages as temporary storage for delta p and | |
204 | * delta q | |
205 | */ | |
206 | dp = blocks[faila]; | |
207 | dq = blocks[failb]; | |
208 | ||
0403e382 | 209 | init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); |
0a82a623 | 210 | tx = async_memcpy(dp, g, 0, 0, bytes, submit); |
0403e382 | 211 | init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); |
0a82a623 DW |
212 | tx = async_mult(dq, g, raid6_gfexp[good], bytes, submit); |
213 | ||
214 | /* compute P + Pxy */ | |
215 | srcs[0] = dp; | |
216 | srcs[1] = p; | |
0403e382 DW |
217 | init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx, |
218 | NULL, NULL, scribble); | |
0a82a623 DW |
219 | tx = async_xor(dp, srcs, 0, 2, bytes, submit); |
220 | ||
221 | /* compute Q + Qxy */ | |
222 | srcs[0] = dq; | |
223 | srcs[1] = q; | |
0403e382 DW |
224 | init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx, |
225 | NULL, NULL, scribble); | |
0a82a623 DW |
226 | tx = async_xor(dq, srcs, 0, 2, bytes, submit); |
227 | ||
228 | /* Dx = A*(P+Pxy) + B*(Q+Qxy) */ | |
229 | srcs[0] = dp; | |
230 | srcs[1] = dq; | |
231 | coef[0] = raid6_gfexi[failb-faila]; | |
232 | coef[1] = raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]]; | |
0403e382 | 233 | init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); |
0a82a623 DW |
234 | tx = async_sum_product(dq, srcs, coef, bytes, submit); |
235 | ||
236 | /* Dy = P+Pxy+Dx */ | |
237 | srcs[0] = dp; | |
238 | srcs[1] = dq; | |
239 | init_async_submit(submit, flags | ASYNC_TX_XOR_DROP_DST, tx, cb_fn, | |
240 | cb_param, scribble); | |
241 | tx = async_xor(dp, srcs, 0, 2, bytes, submit); | |
242 | ||
243 | return tx; | |
244 | } | |
245 | ||
246 | static struct dma_async_tx_descriptor * | |
247 | __2data_recov_n(int disks, size_t bytes, int faila, int failb, | |
248 | struct page **blocks, struct async_submit_ctl *submit) | |
249 | { | |
250 | struct dma_async_tx_descriptor *tx = NULL; | |
251 | struct page *p, *q, *dp, *dq; | |
252 | struct page *srcs[2]; | |
253 | unsigned char coef[2]; | |
254 | enum async_tx_flags flags = submit->flags; | |
255 | dma_async_tx_callback cb_fn = submit->cb_fn; | |
256 | void *cb_param = submit->cb_param; | |
257 | void *scribble = submit->scribble; | |
258 | ||
259 | p = blocks[disks-2]; | |
260 | q = blocks[disks-1]; | |
261 | ||
262 | /* Compute syndrome with zero for the missing data pages | |
263 | * Use the dead data pages as temporary storage for | |
264 | * delta p and delta q | |
265 | */ | |
266 | dp = blocks[faila]; | |
5dd33c9a | 267 | blocks[faila] = NULL; |
0a82a623 DW |
268 | blocks[disks-2] = dp; |
269 | dq = blocks[failb]; | |
5dd33c9a | 270 | blocks[failb] = NULL; |
0a82a623 DW |
271 | blocks[disks-1] = dq; |
272 | ||
0403e382 | 273 | init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); |
0a82a623 DW |
274 | tx = async_gen_syndrome(blocks, 0, disks, bytes, submit); |
275 | ||
276 | /* Restore pointer table */ | |
277 | blocks[faila] = dp; | |
278 | blocks[failb] = dq; | |
279 | blocks[disks-2] = p; | |
280 | blocks[disks-1] = q; | |
281 | ||
282 | /* compute P + Pxy */ | |
283 | srcs[0] = dp; | |
284 | srcs[1] = p; | |
0403e382 DW |
285 | init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx, |
286 | NULL, NULL, scribble); | |
0a82a623 DW |
287 | tx = async_xor(dp, srcs, 0, 2, bytes, submit); |
288 | ||
289 | /* compute Q + Qxy */ | |
290 | srcs[0] = dq; | |
291 | srcs[1] = q; | |
0403e382 DW |
292 | init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx, |
293 | NULL, NULL, scribble); | |
0a82a623 DW |
294 | tx = async_xor(dq, srcs, 0, 2, bytes, submit); |
295 | ||
296 | /* Dx = A*(P+Pxy) + B*(Q+Qxy) */ | |
297 | srcs[0] = dp; | |
298 | srcs[1] = dq; | |
299 | coef[0] = raid6_gfexi[failb-faila]; | |
300 | coef[1] = raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]]; | |
0403e382 | 301 | init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); |
0a82a623 DW |
302 | tx = async_sum_product(dq, srcs, coef, bytes, submit); |
303 | ||
304 | /* Dy = P+Pxy+Dx */ | |
305 | srcs[0] = dp; | |
306 | srcs[1] = dq; | |
307 | init_async_submit(submit, flags | ASYNC_TX_XOR_DROP_DST, tx, cb_fn, | |
308 | cb_param, scribble); | |
309 | tx = async_xor(dp, srcs, 0, 2, bytes, submit); | |
310 | ||
311 | return tx; | |
312 | } | |
313 | ||
314 | /** | |
315 | * async_raid6_2data_recov - asynchronously calculate two missing data blocks | |
316 | * @disks: number of disks in the RAID-6 array | |
317 | * @bytes: block size | |
318 | * @faila: first failed drive index | |
319 | * @failb: second failed drive index | |
320 | * @blocks: array of source pointers where the last two entries are p and q | |
321 | * @submit: submission/completion modifiers | |
322 | */ | |
323 | struct dma_async_tx_descriptor * | |
324 | async_raid6_2data_recov(int disks, size_t bytes, int faila, int failb, | |
325 | struct page **blocks, struct async_submit_ctl *submit) | |
326 | { | |
5157b4aa | 327 | void *scribble = submit->scribble; |
da17bf43 DW |
328 | int non_zero_srcs, i; |
329 | ||
0a82a623 DW |
330 | BUG_ON(faila == failb); |
331 | if (failb < faila) | |
332 | swap(faila, failb); | |
333 | ||
334 | pr_debug("%s: disks: %d len: %zu\n", __func__, disks, bytes); | |
335 | ||
5157b4aa DW |
336 | /* if a dma resource is not available or a scribble buffer is not |
337 | * available punt to the synchronous path. In the 'dma not | |
338 | * available' case be sure to use the scribble buffer to | |
339 | * preserve the content of 'blocks' as the caller intended. | |
0a82a623 | 340 | */ |
5157b4aa DW |
341 | if (!async_dma_find_channel(DMA_PQ) || !scribble) { |
342 | void **ptrs = scribble ? scribble : (void **) blocks; | |
0a82a623 DW |
343 | |
344 | async_tx_quiesce(&submit->depend_tx); | |
345 | for (i = 0; i < disks; i++) | |
5dd33c9a | 346 | if (blocks[i] == NULL) |
da17bf43 | 347 | ptrs[i] = (void *) raid6_empty_zero_page; |
5dd33c9a N |
348 | else |
349 | ptrs[i] = page_address(blocks[i]); | |
0a82a623 DW |
350 | |
351 | raid6_2data_recov(disks, bytes, faila, failb, ptrs); | |
352 | ||
353 | async_tx_sync_epilog(submit); | |
354 | ||
355 | return NULL; | |
356 | } | |
357 | ||
da17bf43 DW |
358 | non_zero_srcs = 0; |
359 | for (i = 0; i < disks-2 && non_zero_srcs < 4; i++) | |
360 | if (blocks[i]) | |
361 | non_zero_srcs++; | |
362 | switch (non_zero_srcs) { | |
363 | case 0: | |
364 | case 1: | |
365 | /* There must be at least 2 sources - the failed devices. */ | |
366 | BUG(); | |
367 | ||
368 | case 2: | |
0a82a623 DW |
369 | /* dma devices do not uniformly understand a zero source pq |
370 | * operation (in contrast to the synchronous case), so | |
da17bf43 DW |
371 | * explicitly handle the special case of a 4 disk array with |
372 | * both data disks missing. | |
0a82a623 | 373 | */ |
da17bf43 DW |
374 | return __2data_recov_4(disks, bytes, faila, failb, blocks, submit); |
375 | case 3: | |
0a82a623 DW |
376 | /* dma devices do not uniformly understand a single |
377 | * source pq operation (in contrast to the synchronous | |
da17bf43 DW |
378 | * case), so explicitly handle the special case of a 5 disk |
379 | * array with 2 of 3 data disks missing. | |
0a82a623 | 380 | */ |
da17bf43 | 381 | return __2data_recov_5(disks, bytes, faila, failb, blocks, submit); |
0a82a623 DW |
382 | default: |
383 | return __2data_recov_n(disks, bytes, faila, failb, blocks, submit); | |
384 | } | |
385 | } | |
386 | EXPORT_SYMBOL_GPL(async_raid6_2data_recov); | |
387 | ||
388 | /** | |
389 | * async_raid6_datap_recov - asynchronously calculate a data and the 'p' block | |
390 | * @disks: number of disks in the RAID-6 array | |
391 | * @bytes: block size | |
392 | * @faila: failed drive index | |
393 | * @blocks: array of source pointers where the last two entries are p and q | |
394 | * @submit: submission/completion modifiers | |
395 | */ | |
396 | struct dma_async_tx_descriptor * | |
397 | async_raid6_datap_recov(int disks, size_t bytes, int faila, | |
398 | struct page **blocks, struct async_submit_ctl *submit) | |
399 | { | |
400 | struct dma_async_tx_descriptor *tx = NULL; | |
401 | struct page *p, *q, *dq; | |
402 | u8 coef; | |
403 | enum async_tx_flags flags = submit->flags; | |
404 | dma_async_tx_callback cb_fn = submit->cb_fn; | |
405 | void *cb_param = submit->cb_param; | |
406 | void *scribble = submit->scribble; | |
da17bf43 | 407 | int good_srcs, good, i; |
0a82a623 DW |
408 | struct page *srcs[2]; |
409 | ||
410 | pr_debug("%s: disks: %d len: %zu\n", __func__, disks, bytes); | |
411 | ||
5157b4aa DW |
412 | /* if a dma resource is not available or a scribble buffer is not |
413 | * available punt to the synchronous path. In the 'dma not | |
414 | * available' case be sure to use the scribble buffer to | |
415 | * preserve the content of 'blocks' as the caller intended. | |
0a82a623 | 416 | */ |
5157b4aa DW |
417 | if (!async_dma_find_channel(DMA_PQ) || !scribble) { |
418 | void **ptrs = scribble ? scribble : (void **) blocks; | |
0a82a623 DW |
419 | |
420 | async_tx_quiesce(&submit->depend_tx); | |
421 | for (i = 0; i < disks; i++) | |
5dd33c9a N |
422 | if (blocks[i] == NULL) |
423 | ptrs[i] = (void*)raid6_empty_zero_page; | |
424 | else | |
425 | ptrs[i] = page_address(blocks[i]); | |
0a82a623 DW |
426 | |
427 | raid6_datap_recov(disks, bytes, faila, ptrs); | |
428 | ||
429 | async_tx_sync_epilog(submit); | |
430 | ||
431 | return NULL; | |
432 | } | |
433 | ||
da17bf43 DW |
434 | good_srcs = 0; |
435 | good = -1; | |
436 | for (i = 0; i < disks-2; i++) { | |
437 | if (i == faila) | |
438 | continue; | |
439 | if (blocks[i]) { | |
440 | good = i; | |
441 | good_srcs++; | |
442 | if (good_srcs > 1) | |
443 | break; | |
444 | } | |
445 | } | |
446 | BUG_ON(good_srcs == 0); | |
447 | ||
0a82a623 DW |
448 | p = blocks[disks-2]; |
449 | q = blocks[disks-1]; | |
450 | ||
451 | /* Compute syndrome with zero for the missing data page | |
452 | * Use the dead data page as temporary storage for delta q | |
453 | */ | |
454 | dq = blocks[faila]; | |
5dd33c9a | 455 | blocks[faila] = NULL; |
0a82a623 DW |
456 | blocks[disks-1] = dq; |
457 | ||
da17bf43 DW |
458 | /* in the 4-disk case we only need to perform a single source |
459 | * multiplication with the one good data block. | |
0a82a623 | 460 | */ |
da17bf43 | 461 | if (good_srcs == 1) { |
0a82a623 DW |
462 | struct page *g = blocks[good]; |
463 | ||
0403e382 DW |
464 | init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, |
465 | scribble); | |
0a82a623 DW |
466 | tx = async_memcpy(p, g, 0, 0, bytes, submit); |
467 | ||
0403e382 DW |
468 | init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, |
469 | scribble); | |
0a82a623 DW |
470 | tx = async_mult(dq, g, raid6_gfexp[good], bytes, submit); |
471 | } else { | |
0403e382 DW |
472 | init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, |
473 | scribble); | |
0a82a623 DW |
474 | tx = async_gen_syndrome(blocks, 0, disks, bytes, submit); |
475 | } | |
476 | ||
477 | /* Restore pointer table */ | |
478 | blocks[faila] = dq; | |
479 | blocks[disks-1] = q; | |
480 | ||
481 | /* calculate g^{-faila} */ | |
482 | coef = raid6_gfinv[raid6_gfexp[faila]]; | |
483 | ||
484 | srcs[0] = dq; | |
485 | srcs[1] = q; | |
0403e382 DW |
486 | init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx, |
487 | NULL, NULL, scribble); | |
0a82a623 DW |
488 | tx = async_xor(dq, srcs, 0, 2, bytes, submit); |
489 | ||
0403e382 | 490 | init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); |
0a82a623 DW |
491 | tx = async_mult(dq, dq, coef, bytes, submit); |
492 | ||
493 | srcs[0] = p; | |
494 | srcs[1] = dq; | |
495 | init_async_submit(submit, flags | ASYNC_TX_XOR_DROP_DST, tx, cb_fn, | |
496 | cb_param, scribble); | |
497 | tx = async_xor(p, srcs, 0, 2, bytes, submit); | |
498 | ||
499 | return tx; | |
500 | } | |
501 | EXPORT_SYMBOL_GPL(async_raid6_datap_recov); | |
502 | ||
503 | MODULE_AUTHOR("Dan Williams <dan.j.williams@intel.com>"); | |
504 | MODULE_DESCRIPTION("asynchronous RAID-6 recovery api"); | |
505 | MODULE_LICENSE("GPL"); |