1 // SPDX-License-Identifier: CDDL-1.0
2 /*
3 * This file and its contents are supplied under the terms of the
4 * Common Development and Distribution License ("CDDL"), version 1.0.
5 * You may only use this file in accordance with the terms of version
6 * 1.0 of the CDDL.
7 *
8 * A full copy of the text of the CDDL should have accompanied this
9 * source. A copy of the CDDL is also available via the Internet at
10 * https://opensource.org/license/CDDL-1.0.
11 */
12 /*
13 * Copyright (C) 2016 Gvozden Nešković. All rights reserved.
14 */
15
16 #include <sys/simd.h>
17 #include <sys/zfs_context.h>
18 #include <sys/types.h>
19 #include <sys/zio.h>
20 #include <sys/debug.h>
21 #include <sys/zfs_debug.h>
22 #include <sys/vdev_raidz.h>
23 #include <sys/vdev_raidz_impl.h>
24
25 /* Opaque implementation with NULL methods to represent original methods */
26 static const raidz_impl_ops_t vdev_raidz_original_impl = {
27 .name = "original",
28 .is_supported = raidz_will_scalar_work,
29 };
30
31 /* RAIDZ parity op that contain the fastest methods */
32 static raidz_impl_ops_t vdev_raidz_fastest_impl = {
33 .name = "fastest"
34 };
35
36 /* All compiled in implementations */
37 static const raidz_impl_ops_t *const raidz_all_maths[] = {
38 &vdev_raidz_original_impl,
39 &vdev_raidz_scalar_impl,
40 #if defined(__x86_64) && HAVE_SIMD(SSE2) /* only x86_64 for now */
41 &vdev_raidz_sse2_impl,
42 #endif
43 #if defined(__x86_64) && HAVE_SIMD(SSSE3) /* only x86_64 for now */
44 &vdev_raidz_ssse3_impl,
45 #endif
46 #if defined(__x86_64) && HAVE_SIMD(AVX2) /* only x86_64 for now */
47 &vdev_raidz_avx2_impl,
48 #endif
49 #if defined(__x86_64) && HAVE_SIMD(AVX512F) /* only x86_64 for now */
50 &vdev_raidz_avx512f_impl,
51 #endif
52 #if defined(__x86_64) && HAVE_SIMD(AVX512BW) /* only x86_64 for now */
53 &vdev_raidz_avx512bw_impl,
54 #endif
55 #if defined(__aarch64__) && !defined(__FreeBSD__)
56 &vdev_raidz_aarch64_neon_impl,
57 &vdev_raidz_aarch64_neonx2_impl,
58 #endif
59 #if defined(__powerpc__) && defined(__altivec__)
60 &vdev_raidz_powerpc_altivec_impl,
61 #endif
62 };
63
64 /* Indicate that benchmark has been completed */
65 static boolean_t raidz_math_initialized = B_FALSE;
66
67 /* Select raidz implementation */
68 #define IMPL_FASTEST (UINT32_MAX)
69 #define IMPL_CYCLE (UINT32_MAX - 1)
70 #define IMPL_ORIGINAL (0)
71 #define IMPL_SCALAR (1)
72
73 #define RAIDZ_IMPL_READ(i) (*(volatile uint32_t *) &(i))
74
75 uint32_t zfs_vdev_raidz_impl = IMPL_SCALAR;
76 static uint32_t user_sel_impl = IMPL_FASTEST;
77
78 /* Hold all supported implementations */
79 static size_t raidz_supp_impl_cnt = 0;
80 static raidz_impl_ops_t *raidz_supp_impl[ARRAY_SIZE(raidz_all_maths)];
81
82 #if defined(_KERNEL)
83 /*
84 * kstats values for supported implementations
85 * Values represent per disk throughput of 8 disk+parity raidz vdev [B/s]
86 */
87 static raidz_impl_kstat_t raidz_impl_kstats[ARRAY_SIZE(raidz_all_maths) + 1];
88
89 /* kstat for benchmarked implementations */
90 static kstat_t *raidz_math_kstat = NULL;
91 #endif
92
93 /*
94 * Returns the RAIDZ operations for raidz_map() parity calculations. When
95 * a SIMD implementation is not allowed in the current context, then fallback
96 * to the fastest generic implementation.
97 */
98 const raidz_impl_ops_t *
vdev_raidz_math_get_ops(void)99 vdev_raidz_math_get_ops(void)
100 {
101 if (!kfpu_allowed())
102 return (&vdev_raidz_scalar_impl);
103
104 raidz_impl_ops_t *ops = NULL;
105 const uint32_t impl = RAIDZ_IMPL_READ(zfs_vdev_raidz_impl);
106
107 switch (impl) {
108 case IMPL_FASTEST:
109 ASSERT(raidz_math_initialized);
110 ops = &vdev_raidz_fastest_impl;
111 break;
112 case IMPL_CYCLE:
113 /* Cycle through all supported implementations */
114 ASSERT(raidz_math_initialized);
115 ASSERT3U(raidz_supp_impl_cnt, >, 0);
116 static size_t cycle_impl_idx = 0;
117 size_t idx = (++cycle_impl_idx) % raidz_supp_impl_cnt;
118 ops = raidz_supp_impl[idx];
119 break;
120 case IMPL_ORIGINAL:
121 ops = (raidz_impl_ops_t *)&vdev_raidz_original_impl;
122 break;
123 case IMPL_SCALAR:
124 ops = (raidz_impl_ops_t *)&vdev_raidz_scalar_impl;
125 break;
126 default:
127 ASSERT3U(impl, <, raidz_supp_impl_cnt);
128 ASSERT3U(raidz_supp_impl_cnt, >, 0);
129 if (impl < ARRAY_SIZE(raidz_all_maths))
130 ops = raidz_supp_impl[impl];
131 break;
132 }
133
134 ASSERT3P(ops, !=, NULL);
135
136 return (ops);
137 }
138
139 /*
140 * Select parity generation method for raidz_map
141 */
142 int
vdev_raidz_math_generate(raidz_map_t * rm,raidz_row_t * rr)143 vdev_raidz_math_generate(raidz_map_t *rm, raidz_row_t *rr)
144 {
145 raidz_gen_f gen_parity = NULL;
146
147 switch (raidz_parity(rm)) {
148 case 1:
149 gen_parity = rm->rm_ops->gen[RAIDZ_GEN_P];
150 break;
151 case 2:
152 gen_parity = rm->rm_ops->gen[RAIDZ_GEN_PQ];
153 break;
154 case 3:
155 gen_parity = rm->rm_ops->gen[RAIDZ_GEN_PQR];
156 break;
157 default:
158 gen_parity = NULL;
159 cmn_err(CE_PANIC, "invalid RAID-Z configuration %llu",
160 (u_longlong_t)raidz_parity(rm));
161 break;
162 }
163
164 /* if method is NULL execute the original implementation */
165 if (gen_parity == NULL)
166 return (RAIDZ_ORIGINAL_IMPL);
167
168 gen_parity(rr);
169
170 return (0);
171 }
172
173 static raidz_rec_f
reconstruct_fun_p_sel(raidz_map_t * rm,const int * parity_valid,const int nbaddata)174 reconstruct_fun_p_sel(raidz_map_t *rm, const int *parity_valid,
175 const int nbaddata)
176 {
177 if (nbaddata == 1 && parity_valid[CODE_P]) {
178 return (rm->rm_ops->rec[RAIDZ_REC_P]);
179 }
180 return ((raidz_rec_f) NULL);
181 }
182
183 static raidz_rec_f
reconstruct_fun_pq_sel(raidz_map_t * rm,const int * parity_valid,const int nbaddata)184 reconstruct_fun_pq_sel(raidz_map_t *rm, const int *parity_valid,
185 const int nbaddata)
186 {
187 if (nbaddata == 1) {
188 if (parity_valid[CODE_P]) {
189 return (rm->rm_ops->rec[RAIDZ_REC_P]);
190 } else if (parity_valid[CODE_Q]) {
191 return (rm->rm_ops->rec[RAIDZ_REC_Q]);
192 }
193 } else if (nbaddata == 2 &&
194 parity_valid[CODE_P] && parity_valid[CODE_Q]) {
195 return (rm->rm_ops->rec[RAIDZ_REC_PQ]);
196 }
197 return ((raidz_rec_f) NULL);
198 }
199
200 static raidz_rec_f
reconstruct_fun_pqr_sel(raidz_map_t * rm,const int * parity_valid,const int nbaddata)201 reconstruct_fun_pqr_sel(raidz_map_t *rm, const int *parity_valid,
202 const int nbaddata)
203 {
204 if (nbaddata == 1) {
205 if (parity_valid[CODE_P]) {
206 return (rm->rm_ops->rec[RAIDZ_REC_P]);
207 } else if (parity_valid[CODE_Q]) {
208 return (rm->rm_ops->rec[RAIDZ_REC_Q]);
209 } else if (parity_valid[CODE_R]) {
210 return (rm->rm_ops->rec[RAIDZ_REC_R]);
211 }
212 } else if (nbaddata == 2) {
213 if (parity_valid[CODE_P] && parity_valid[CODE_Q]) {
214 return (rm->rm_ops->rec[RAIDZ_REC_PQ]);
215 } else if (parity_valid[CODE_P] && parity_valid[CODE_R]) {
216 return (rm->rm_ops->rec[RAIDZ_REC_PR]);
217 } else if (parity_valid[CODE_Q] && parity_valid[CODE_R]) {
218 return (rm->rm_ops->rec[RAIDZ_REC_QR]);
219 }
220 } else if (nbaddata == 3 &&
221 parity_valid[CODE_P] && parity_valid[CODE_Q] &&
222 parity_valid[CODE_R]) {
223 return (rm->rm_ops->rec[RAIDZ_REC_PQR]);
224 }
225 return ((raidz_rec_f) NULL);
226 }
227
228 /*
229 * Select data reconstruction method for raidz_map
230 * @parity_valid - Parity validity flag
231 * @dt - Failed data index array
232 * @nbaddata - Number of failed data columns
233 */
234 int
vdev_raidz_math_reconstruct(raidz_map_t * rm,raidz_row_t * rr,const int * parity_valid,const int * dt,const int nbaddata)235 vdev_raidz_math_reconstruct(raidz_map_t *rm, raidz_row_t *rr,
236 const int *parity_valid, const int *dt, const int nbaddata)
237 {
238 raidz_rec_f rec_fn = NULL;
239
240 switch (raidz_parity(rm)) {
241 case PARITY_P:
242 rec_fn = reconstruct_fun_p_sel(rm, parity_valid, nbaddata);
243 break;
244 case PARITY_PQ:
245 rec_fn = reconstruct_fun_pq_sel(rm, parity_valid, nbaddata);
246 break;
247 case PARITY_PQR:
248 rec_fn = reconstruct_fun_pqr_sel(rm, parity_valid, nbaddata);
249 break;
250 default:
251 cmn_err(CE_PANIC, "invalid RAID-Z configuration %llu",
252 (u_longlong_t)raidz_parity(rm));
253 break;
254 }
255
256 if (rec_fn == NULL)
257 return (RAIDZ_ORIGINAL_IMPL);
258 else
259 return (rec_fn(rr, dt));
260 }
261
262 const char *const raidz_gen_name[] = {
263 "gen_p", "gen_pq", "gen_pqr"
264 };
265 const char *const raidz_rec_name[] = {
266 "rec_p", "rec_q", "rec_r",
267 "rec_pq", "rec_pr", "rec_qr", "rec_pqr"
268 };
269
270 #if defined(_KERNEL)
271
272 #define RAIDZ_KSTAT_LINE_LEN (17 + 10*12 + 1)
273
274 static int
raidz_math_kstat_headers(char * buf,size_t size)275 raidz_math_kstat_headers(char *buf, size_t size)
276 {
277 ASSERT3U(size, >=, RAIDZ_KSTAT_LINE_LEN);
278
279 ssize_t off = kmem_scnprintf(buf, size, "%-17s", "implementation");
280
281 for (int i = 0; i < ARRAY_SIZE(raidz_gen_name); i++)
282 off += kmem_scnprintf(buf + off, size - off, "%-16s",
283 raidz_gen_name[i]);
284
285 for (int i = 0; i < ARRAY_SIZE(raidz_rec_name); i++)
286 off += kmem_scnprintf(buf + off, size - off, "%-16s",
287 raidz_rec_name[i]);
288
289 (void) kmem_scnprintf(buf + off, size - off, "\n");
290
291 return (0);
292 }
293
294 static int
raidz_math_kstat_data(char * buf,size_t size,void * data)295 raidz_math_kstat_data(char *buf, size_t size, void *data)
296 {
297 raidz_impl_kstat_t *fstat = &raidz_impl_kstats[raidz_supp_impl_cnt];
298 raidz_impl_kstat_t *cstat = (raidz_impl_kstat_t *)data;
299 ssize_t off = 0;
300 int i;
301
302 ASSERT3U(size, >=, RAIDZ_KSTAT_LINE_LEN);
303
304 if (cstat == fstat) {
305 off += kmem_scnprintf(buf + off, size - off, "%-17s",
306 "fastest");
307
308 for (i = 0; i < ARRAY_SIZE(raidz_gen_name); i++) {
309 int id = fstat->gen[i];
310 off += kmem_scnprintf(buf + off, size - off, "%-16s",
311 raidz_supp_impl[id]->name);
312 }
313 for (i = 0; i < ARRAY_SIZE(raidz_rec_name); i++) {
314 int id = fstat->rec[i];
315 off += kmem_scnprintf(buf + off, size - off, "%-16s",
316 raidz_supp_impl[id]->name);
317 }
318 } else {
319 ptrdiff_t id = cstat - raidz_impl_kstats;
320
321 off += kmem_scnprintf(buf + off, size - off, "%-17s",
322 raidz_supp_impl[id]->name);
323
324 for (i = 0; i < ARRAY_SIZE(raidz_gen_name); i++)
325 off += kmem_scnprintf(buf + off, size - off, "%-16llu",
326 (u_longlong_t)cstat->gen[i]);
327
328 for (i = 0; i < ARRAY_SIZE(raidz_rec_name); i++)
329 off += kmem_scnprintf(buf + off, size - off, "%-16llu",
330 (u_longlong_t)cstat->rec[i]);
331 }
332
333 (void) kmem_scnprintf(buf + off, size - off, "\n");
334
335 return (0);
336 }
337
338 static void *
raidz_math_kstat_addr(kstat_t * ksp,loff_t n)339 raidz_math_kstat_addr(kstat_t *ksp, loff_t n)
340 {
341 if (n <= raidz_supp_impl_cnt)
342 ksp->ks_private = (void *) (raidz_impl_kstats + n);
343 else
344 ksp->ks_private = NULL;
345
346 return (ksp->ks_private);
347 }
348
349 #define BENCH_D_COLS (8ULL)
350 #define BENCH_COLS (BENCH_D_COLS + PARITY_PQR)
351 #define BENCH_ZIO_SIZE (1ULL << SPA_OLD_MAXBLOCKSHIFT) /* 128 kiB */
352 #define BENCH_NS MSEC2NSEC(1) /* 1ms */
353
354 typedef void (*benchmark_fn)(raidz_map_t *rm, const int fn);
355
356 static void
benchmark_gen_impl(raidz_map_t * rm,const int fn)357 benchmark_gen_impl(raidz_map_t *rm, const int fn)
358 {
359 (void) fn;
360 vdev_raidz_generate_parity(rm);
361 }
362
363 static void
benchmark_rec_impl(raidz_map_t * rm,const int fn)364 benchmark_rec_impl(raidz_map_t *rm, const int fn)
365 {
366 static const int rec_tgt[7][3] = {
367 {1, 2, 3}, /* rec_p: bad QR & D[0] */
368 {0, 2, 3}, /* rec_q: bad PR & D[0] */
369 {0, 1, 3}, /* rec_r: bad PQ & D[0] */
370 {2, 3, 4}, /* rec_pq: bad R & D[0][1] */
371 {1, 3, 4}, /* rec_pr: bad Q & D[0][1] */
372 {0, 3, 4}, /* rec_qr: bad P & D[0][1] */
373 {3, 4, 5} /* rec_pqr: bad & D[0][1][2] */
374 };
375
376 vdev_raidz_reconstruct(rm, rec_tgt[fn], 3);
377 }
378
379 /*
380 * Benchmarking of all supported implementations (raidz_supp_impl_cnt)
381 * is performed by setting the rm_ops pointer and calling the top level
382 * generate/reconstruct methods of bench_rm.
383 */
384 static void
benchmark_raidz_impl(raidz_map_t * bench_rm,const int fn,benchmark_fn bench_fn)385 benchmark_raidz_impl(raidz_map_t *bench_rm, const int fn, benchmark_fn bench_fn)
386 {
387 uint64_t run_cnt, speed, best_speed = 0;
388 hrtime_t t_start, t_diff;
389 raidz_impl_ops_t *curr_impl;
390 raidz_impl_kstat_t *fstat = &raidz_impl_kstats[raidz_supp_impl_cnt];
391 int impl, i;
392
393 for (impl = 0; impl < raidz_supp_impl_cnt; impl++) {
394 /* set an implementation to benchmark */
395 curr_impl = raidz_supp_impl[impl];
396 bench_rm->rm_ops = curr_impl;
397
398 run_cnt = 0;
399 t_start = gethrtime();
400
401 do {
402 for (i = 0; i < 5; i++, run_cnt++)
403 bench_fn(bench_rm, fn);
404
405 t_diff = gethrtime() - t_start;
406 } while (t_diff < BENCH_NS);
407
408 speed = run_cnt * BENCH_ZIO_SIZE * NANOSEC;
409 speed /= (t_diff * BENCH_COLS);
410
411 if (bench_fn == benchmark_gen_impl)
412 raidz_impl_kstats[impl].gen[fn] = speed;
413 else
414 raidz_impl_kstats[impl].rec[fn] = speed;
415
416 /* Update fastest implementation method */
417 if (speed > best_speed) {
418 best_speed = speed;
419
420 if (bench_fn == benchmark_gen_impl) {
421 fstat->gen[fn] = impl;
422 vdev_raidz_fastest_impl.gen[fn] =
423 curr_impl->gen[fn];
424 } else {
425 fstat->rec[fn] = impl;
426 vdev_raidz_fastest_impl.rec[fn] =
427 curr_impl->rec[fn];
428 }
429 }
430 }
431 }
432 #endif
433
434 /*
435 * Initialize and benchmark all supported implementations.
436 */
437 static void
benchmark_raidz(void)438 benchmark_raidz(void)
439 {
440 raidz_impl_ops_t *curr_impl;
441 int i, c;
442
443 /* Move supported impl into raidz_supp_impl */
444 for (i = 0, c = 0; i < ARRAY_SIZE(raidz_all_maths); i++) {
445 curr_impl = (raidz_impl_ops_t *)raidz_all_maths[i];
446
447 if (curr_impl->init)
448 curr_impl->init();
449
450 if (curr_impl->is_supported())
451 raidz_supp_impl[c++] = (raidz_impl_ops_t *)curr_impl;
452 }
453 membar_producer(); /* complete raidz_supp_impl[] init */
454 raidz_supp_impl_cnt = c; /* number of supported impl */
455
456 #if defined(_KERNEL)
457 abd_t *pabd;
458 zio_t *bench_zio = NULL;
459 raidz_map_t *bench_rm = NULL;
460 uint64_t bench_parity;
461
462 /* Fake a zio and run the benchmark on a warmed up buffer */
463 bench_zio = kmem_zalloc(sizeof (zio_t), KM_SLEEP);
464 bench_zio->io_offset = 0;
465 bench_zio->io_size = BENCH_ZIO_SIZE; /* only data columns */
466 bench_zio->io_abd = abd_alloc_linear(BENCH_ZIO_SIZE, B_TRUE);
467 memset(abd_to_buf(bench_zio->io_abd), 0xAA, BENCH_ZIO_SIZE);
468
469 /* Benchmark parity generation methods */
470 for (int fn = 0; fn < RAIDZ_GEN_NUM; fn++) {
471 bench_parity = fn + 1;
472 /* New raidz_map is needed for each generate_p/q/r */
473 bench_rm = vdev_raidz_map_alloc(bench_zio, SPA_MINBLOCKSHIFT,
474 BENCH_D_COLS + bench_parity, bench_parity);
475
476 benchmark_raidz_impl(bench_rm, fn, benchmark_gen_impl);
477
478 vdev_raidz_map_free(bench_rm);
479 }
480
481 /* Benchmark data reconstruction methods */
482 bench_rm = vdev_raidz_map_alloc(bench_zio, SPA_MINBLOCKSHIFT,
483 BENCH_COLS, PARITY_PQR);
484
485 /* Ensure that fake parity blocks are initialized */
486 for (c = 0; c < bench_rm->rm_row[0]->rr_firstdatacol; c++) {
487 pabd = bench_rm->rm_row[0]->rr_col[c].rc_abd;
488 memset(abd_to_buf(pabd), 0xAA, abd_get_size(pabd));
489 }
490
491 for (int fn = 0; fn < RAIDZ_REC_NUM; fn++)
492 benchmark_raidz_impl(bench_rm, fn, benchmark_rec_impl);
493
494 vdev_raidz_map_free(bench_rm);
495
496 /* cleanup the bench zio */
497 abd_free(bench_zio->io_abd);
498 kmem_free(bench_zio, sizeof (zio_t));
499 #else
500 /*
501 * Skip the benchmark in user space to avoid impacting libzpool
502 * consumers (zdb, zhack, zinject, ztest). The last implementation
503 * is assumed to be the fastest and used by default.
504 */
505 memcpy(&vdev_raidz_fastest_impl,
506 raidz_supp_impl[raidz_supp_impl_cnt - 1],
507 sizeof (vdev_raidz_fastest_impl));
508 strcpy(vdev_raidz_fastest_impl.name, "fastest");
509 #endif /* _KERNEL */
510 }
511
512 void
vdev_raidz_math_init(void)513 vdev_raidz_math_init(void)
514 {
515 /* Determine the fastest available implementation. */
516 benchmark_raidz();
517
518 #if defined(_KERNEL)
519 /* Install kstats for all implementations */
520 raidz_math_kstat = kstat_create("zfs", 0, "vdev_raidz_bench", "misc",
521 KSTAT_TYPE_RAW, 0, KSTAT_FLAG_VIRTUAL);
522 if (raidz_math_kstat != NULL) {
523 raidz_math_kstat->ks_data = NULL;
524 raidz_math_kstat->ks_ndata = UINT32_MAX;
525 kstat_set_raw_ops(raidz_math_kstat,
526 raidz_math_kstat_headers,
527 raidz_math_kstat_data,
528 raidz_math_kstat_addr);
529 kstat_install(raidz_math_kstat);
530 }
531 #endif
532
533 /* Finish initialization */
534 atomic_swap_32(&zfs_vdev_raidz_impl, user_sel_impl);
535 raidz_math_initialized = B_TRUE;
536 }
537
538 void
vdev_raidz_math_fini(void)539 vdev_raidz_math_fini(void)
540 {
541 raidz_impl_ops_t const *curr_impl;
542
543 #if defined(_KERNEL)
544 if (raidz_math_kstat != NULL) {
545 kstat_delete(raidz_math_kstat);
546 raidz_math_kstat = NULL;
547 }
548 #endif
549
550 for (int i = 0; i < ARRAY_SIZE(raidz_all_maths); i++) {
551 curr_impl = raidz_all_maths[i];
552 if (curr_impl->fini)
553 curr_impl->fini();
554 }
555 }
556
557 static const struct {
558 const char *name;
559 uint32_t sel;
560 } math_impl_opts[] = {
561 { "cycle", IMPL_CYCLE },
562 { "fastest", IMPL_FASTEST },
563 { "original", IMPL_ORIGINAL },
564 { "scalar", IMPL_SCALAR }
565 };
566
567 /*
568 * Function sets desired raidz implementation.
569 *
570 * If we are called before init(), user preference will be saved in
571 * user_sel_impl, and applied in later init() call. This occurs when module
572 * parameter is specified on module load. Otherwise, directly update
573 * zfs_vdev_raidz_impl.
574 *
575 * @val Name of raidz implementation to use
576 * @param Unused.
577 */
578 int
vdev_raidz_impl_set(const char * val)579 vdev_raidz_impl_set(const char *val)
580 {
581 int err = -EINVAL;
582 char req_name[RAIDZ_IMPL_NAME_MAX];
583 uint32_t impl = RAIDZ_IMPL_READ(user_sel_impl);
584 size_t i;
585
586 /* sanitize input */
587 i = strnlen(val, RAIDZ_IMPL_NAME_MAX);
588 if (i == 0 || i == RAIDZ_IMPL_NAME_MAX)
589 return (err);
590
591 strlcpy(req_name, val, RAIDZ_IMPL_NAME_MAX);
592 while (i > 0 && !!isspace(req_name[i-1]))
593 i--;
594 req_name[i] = '\0';
595
596 /* Check mandatory options */
597 for (i = 0; i < ARRAY_SIZE(math_impl_opts); i++) {
598 if (strcmp(req_name, math_impl_opts[i].name) == 0) {
599 impl = math_impl_opts[i].sel;
600 err = 0;
601 break;
602 }
603 }
604
605 /* check all supported impl if init() was already called */
606 if (err != 0 && raidz_math_initialized) {
607 /* check all supported implementations */
608 for (i = 0; i < raidz_supp_impl_cnt; i++) {
609 if (strcmp(req_name, raidz_supp_impl[i]->name) == 0) {
610 impl = i;
611 err = 0;
612 break;
613 }
614 }
615 }
616
617 if (err == 0) {
618 if (raidz_math_initialized)
619 atomic_swap_32(&zfs_vdev_raidz_impl, impl);
620 else
621 atomic_swap_32(&user_sel_impl, impl);
622 }
623
624 return (err);
625 }
626
627 #if defined(_KERNEL)
628
629 int
vdev_raidz_impl_get(char * buffer,size_t size)630 vdev_raidz_impl_get(char *buffer, size_t size)
631 {
632 int i, cnt = 0;
633 char *fmt;
634 const uint32_t impl = RAIDZ_IMPL_READ(zfs_vdev_raidz_impl);
635
636 /* list mandatory options */
637 for (i = 0; i < ARRAY_SIZE(math_impl_opts) - 2; i++) {
638 fmt = (impl == math_impl_opts[i].sel) ? "[%s] " : "%s ";
639 cnt += kmem_scnprintf(buffer + cnt, size - cnt, fmt,
640 math_impl_opts[i].name);
641 }
642
643 /* list all supported implementations */
644 for (i = 0; i < raidz_supp_impl_cnt; i++) {
645 fmt = (i == impl) ? "[%s] " : "%s ";
646 cnt += kmem_scnprintf(buffer + cnt, size - cnt, fmt,
647 raidz_supp_impl[i]->name);
648 }
649
650 return (cnt);
651 }
652
653 #endif
654