/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright 2009 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. * Copyright (C) 2016 Gvozden Nešković. All rights reserved. */ /* * Copyright 2013 Saso Kiselkov. All rights reserved. */ /* * Copyright (c) 2016 by Delphix. All rights reserved. */ /* * Fletcher Checksums * ------------------ * * ZFS's 2nd and 4th order Fletcher checksums are defined by the following * recurrence relations: * * a = a + f * i i-1 i-1 * * b = b + a * i i-1 i * * c = c + b (fletcher-4 only) * i i-1 i * * d = d + c (fletcher-4 only) * i i-1 i * * Where * a_0 = b_0 = c_0 = d_0 = 0 * and * f_0 .. f_(n-1) are the input data. * * Using standard techniques, these translate into the following series: * * __n_ __n_ * \ | \ | * a = > f b = > i * f * n /___| n - i n /___| n - i * i = 1 i = 1 * * * __n_ __n_ * \ | i*(i+1) \ | i*(i+1)*(i+2) * c = > ------- f d = > ------------- f * n /___| 2 n - i n /___| 6 n - i * i = 1 i = 1 * * For fletcher-2, the f_is are 64-bit, and [ab]_i are 64-bit accumulators. * Since the additions are done mod (2^64), errors in the high bits may not * be noticed. For this reason, fletcher-2 is deprecated. * * For fletcher-4, the f_is are 32-bit, and [abcd]_i are 64-bit accumulators. * A conservative estimate of how big the buffer can get before we overflow * can be estimated using f_i = 0xffffffff for all i: * * % bc * f=2^32-1;d=0; for (i = 1; d<2^64; i++) { d += f*i*(i+1)*(i+2)/6 }; (i-1)*4 * 2264 * quit * % * * So blocks of up to 2k will not overflow. Our largest block size is * 128k, which has 32k 4-byte words, so we can compute the largest possible * accumulators, then divide by 2^64 to figure the max amount of overflow: * * % bc * a=b=c=d=0; f=2^32-1; for (i=1; i<=32*1024; i++) { a+=f; b+=a; c+=b; d+=c } * a/2^64;b/2^64;c/2^64;d/2^64 * 0 * 0 * 1365 * 11186858 * quit * % * * So a and b cannot overflow. To make sure each bit of input has some * effect on the contents of c and d, we can look at what the factors of * the coefficients in the equations for c_n and d_n are. The number of 2s * in the factors determines the lowest set bit in the multiplier. Running * through the cases for n*(n+1)/2 reveals that the highest power of 2 is * 2^14, and for n*(n+1)*(n+2)/6 it is 2^15. So while some data may overflow * the 64-bit accumulators, every bit of every f_i effects every accumulator, * even for 128k blocks. * * If we wanted to make a stronger version of fletcher4 (fletcher4c?), * we could do our calculations mod (2^32 - 1) by adding in the carries * periodically, and store the number of carries in the top 32-bits. * * -------------------- * Checksum Performance * -------------------- * * There are two interesting components to checksum performance: cached and * uncached performance. With cached data, fletcher-2 is about four times * faster than fletcher-4. With uncached data, the performance difference is * negligible, since the cost of a cache fill dominates the processing time. * Even though fletcher-4 is slower than fletcher-2, it is still a pretty * efficient pass over the data. * * In normal operation, the data which is being checksummed is in a buffer * which has been filled either by: * * 1. a compression step, which will be mostly cached, or * 2. a bcopy() or copyin(), which will be uncached (because the * copy is cache-bypassing). * * For both cached and uncached data, both fletcher checksums are much faster * than sha-256, and slower than 'off', which doesn't touch the data at all. */ #include #include #include #include #include #include #include #include #define FLETCHER_MIN_SIMD_SIZE 64 static void fletcher_4_scalar_init(fletcher_4_ctx_t *ctx); static void fletcher_4_scalar_fini(fletcher_4_ctx_t *ctx, zio_cksum_t *zcp); static void fletcher_4_scalar_native(fletcher_4_ctx_t *ctx, const void *buf, uint64_t size); static void fletcher_4_scalar_byteswap(fletcher_4_ctx_t *ctx, const void *buf, uint64_t size); static boolean_t fletcher_4_scalar_valid(void); static const fletcher_4_ops_t fletcher_4_scalar_ops = { .init_native = fletcher_4_scalar_init, .fini_native = fletcher_4_scalar_fini, .compute_native = fletcher_4_scalar_native, .init_byteswap = fletcher_4_scalar_init, .fini_byteswap = fletcher_4_scalar_fini, .compute_byteswap = fletcher_4_scalar_byteswap, .valid = fletcher_4_scalar_valid, .name = "scalar" }; static fletcher_4_ops_t fletcher_4_fastest_impl = { .name = "fastest", .valid = fletcher_4_scalar_valid }; static const fletcher_4_ops_t *fletcher_4_impls[] = { &fletcher_4_scalar_ops, &fletcher_4_superscalar_ops, &fletcher_4_superscalar4_ops, #if defined(HAVE_SSE2) &fletcher_4_sse2_ops, #endif #if defined(HAVE_SSE2) && defined(HAVE_SSSE3) &fletcher_4_ssse3_ops, #endif #if defined(HAVE_AVX) && defined(HAVE_AVX2) &fletcher_4_avx2_ops, #endif #if defined(__x86_64) && defined(HAVE_AVX512F) &fletcher_4_avx512f_ops, #endif #if defined(__x86_64) && defined(HAVE_AVX512BW) &fletcher_4_avx512bw_ops, #endif #if defined(__aarch64__) && !defined(__FreeBSD__) &fletcher_4_aarch64_neon_ops, #endif }; /* Hold all supported implementations */ static uint32_t fletcher_4_supp_impls_cnt = 0; static fletcher_4_ops_t *fletcher_4_supp_impls[ARRAY_SIZE(fletcher_4_impls)]; /* Select fletcher4 implementation */ #define IMPL_FASTEST (UINT32_MAX) #define IMPL_CYCLE (UINT32_MAX - 1) #define IMPL_SCALAR (0) static uint32_t fletcher_4_impl_chosen = IMPL_FASTEST; #define IMPL_READ(i) (*(volatile uint32_t *) &(i)) static struct fletcher_4_impl_selector { const char *fis_name; uint32_t fis_sel; } fletcher_4_impl_selectors[] = { { "cycle", IMPL_CYCLE }, { "fastest", IMPL_FASTEST }, { "scalar", IMPL_SCALAR } }; #if defined(_KERNEL) static kstat_t *fletcher_4_kstat; static struct fletcher_4_kstat { uint64_t native; uint64_t byteswap; } fletcher_4_stat_data[ARRAY_SIZE(fletcher_4_impls) + 1]; #endif /* Indicate that benchmark has been completed */ static boolean_t fletcher_4_initialized = B_FALSE; /*ARGSUSED*/ void fletcher_init(zio_cksum_t *zcp) { ZIO_SET_CHECKSUM(zcp, 0, 0, 0, 0); } int fletcher_2_incremental_native(void *buf, size_t size, void *data) { zio_cksum_t *zcp = data; const uint64_t *ip = buf; const uint64_t *ipend = ip + (size / sizeof (uint64_t)); uint64_t a0, b0, a1, b1; a0 = zcp->zc_word[0]; a1 = zcp->zc_word[1]; b0 = zcp->zc_word[2]; b1 = zcp->zc_word[3]; for (; ip < ipend; ip += 2) { a0 += ip[0]; a1 += ip[1]; b0 += a0; b1 += a1; } ZIO_SET_CHECKSUM(zcp, a0, a1, b0, b1); return (0); } /*ARGSUSED*/ void fletcher_2_native(const void *buf, uint64_t size, const void *ctx_template, zio_cksum_t *zcp) { fletcher_init(zcp); (void) fletcher_2_incremental_native((void *) buf, size, zcp); } int fletcher_2_incremental_byteswap(void *buf, size_t size, void *data) { zio_cksum_t *zcp = data; const uint64_t *ip = buf; const uint64_t *ipend = ip + (size / sizeof (uint64_t)); uint64_t a0, b0, a1, b1; a0 = zcp->zc_word[0]; a1 = zcp->zc_word[1]; b0 = zcp->zc_word[2]; b1 = zcp->zc_word[3]; for (; ip < ipend; ip += 2) { a0 += BSWAP_64(ip[0]); a1 += BSWAP_64(ip[1]); b0 += a0; b1 += a1; } ZIO_SET_CHECKSUM(zcp, a0, a1, b0, b1); return (0); } /*ARGSUSED*/ void fletcher_2_byteswap(const void *buf, uint64_t size, const void *ctx_template, zio_cksum_t *zcp) { fletcher_init(zcp); (void) fletcher_2_incremental_byteswap((void *) buf, size, zcp); } static void fletcher_4_scalar_init(fletcher_4_ctx_t *ctx) { ZIO_SET_CHECKSUM(&ctx->scalar, 0, 0, 0, 0); } static void fletcher_4_scalar_fini(fletcher_4_ctx_t *ctx, zio_cksum_t *zcp) { memcpy(zcp, &ctx->scalar, sizeof (zio_cksum_t)); } static void fletcher_4_scalar_native(fletcher_4_ctx_t *ctx, const void *buf, uint64_t size) { const uint32_t *ip = buf; const uint32_t *ipend = ip + (size / sizeof (uint32_t)); uint64_t a, b, c, d; a = ctx->scalar.zc_word[0]; b = ctx->scalar.zc_word[1]; c = ctx->scalar.zc_word[2]; d = ctx->scalar.zc_word[3]; for (; ip < ipend; ip++) { a += ip[0]; b += a; c += b; d += c; } ZIO_SET_CHECKSUM(&ctx->scalar, a, b, c, d); } static void fletcher_4_scalar_byteswap(fletcher_4_ctx_t *ctx, const void *buf, uint64_t size) { const uint32_t *ip = buf; const uint32_t *ipend = ip + (size / sizeof (uint32_t)); uint64_t a, b, c, d; a = ctx->scalar.zc_word[0]; b = ctx->scalar.zc_word[1]; c = ctx->scalar.zc_word[2]; d = ctx->scalar.zc_word[3]; for (; ip < ipend; ip++) { a += BSWAP_32(ip[0]); b += a; c += b; d += c; } ZIO_SET_CHECKSUM(&ctx->scalar, a, b, c, d); } static boolean_t fletcher_4_scalar_valid(void) { return (B_TRUE); } int fletcher_4_impl_set(const char *val) { int err = -EINVAL; uint32_t impl = IMPL_READ(fletcher_4_impl_chosen); size_t i, val_len; val_len = strlen(val); while ((val_len > 0) && !!isspace(val[val_len-1])) /* trim '\n' */ val_len--; /* check mandatory implementations */ for (i = 0; i < ARRAY_SIZE(fletcher_4_impl_selectors); i++) { const char *name = fletcher_4_impl_selectors[i].fis_name; if (val_len == strlen(name) && strncmp(val, name, val_len) == 0) { impl = fletcher_4_impl_selectors[i].fis_sel; err = 0; break; } } if (err != 0 && fletcher_4_initialized) { /* check all supported implementations */ for (i = 0; i < fletcher_4_supp_impls_cnt; i++) { const char *name = fletcher_4_supp_impls[i]->name; if (val_len == strlen(name) && strncmp(val, name, val_len) == 0) { impl = i; err = 0; break; } } } if (err == 0) { atomic_swap_32(&fletcher_4_impl_chosen, impl); membar_producer(); } return (err); } /* * Returns the Fletcher 4 operations for checksums. When a SIMD * implementation is not allowed in the current context, then fallback * to the fastest generic implementation. */ static inline const fletcher_4_ops_t * fletcher_4_impl_get(void) { if (!kfpu_allowed()) return (&fletcher_4_superscalar4_ops); const fletcher_4_ops_t *ops = NULL; uint32_t impl = IMPL_READ(fletcher_4_impl_chosen); switch (impl) { case IMPL_FASTEST: ASSERT(fletcher_4_initialized); ops = &fletcher_4_fastest_impl; break; case IMPL_CYCLE: /* Cycle through supported implementations */ ASSERT(fletcher_4_initialized); ASSERT3U(fletcher_4_supp_impls_cnt, >, 0); static uint32_t cycle_count = 0; uint32_t idx = (++cycle_count) % fletcher_4_supp_impls_cnt; ops = fletcher_4_supp_impls[idx]; break; default: ASSERT3U(fletcher_4_supp_impls_cnt, >, 0); ASSERT3U(impl, <, fletcher_4_supp_impls_cnt); ops = fletcher_4_supp_impls[impl]; break; } ASSERT3P(ops, !=, NULL); return (ops); } static inline void fletcher_4_native_impl(const void *buf, uint64_t size, zio_cksum_t *zcp) { fletcher_4_ctx_t ctx; const fletcher_4_ops_t *ops = fletcher_4_impl_get(); ops->init_native(&ctx); ops->compute_native(&ctx, buf, size); ops->fini_native(&ctx, zcp); } /*ARGSUSED*/ void fletcher_4_native(const void *buf, uint64_t size, const void *ctx_template, zio_cksum_t *zcp) { const uint64_t p2size = P2ALIGN(size, FLETCHER_MIN_SIMD_SIZE); ASSERT(IS_P2ALIGNED(size, sizeof (uint32_t))); if (size == 0 || p2size == 0) { ZIO_SET_CHECKSUM(zcp, 0, 0, 0, 0); if (size > 0) fletcher_4_scalar_native((fletcher_4_ctx_t *)zcp, buf, size); } else { fletcher_4_native_impl(buf, p2size, zcp); if (p2size < size) fletcher_4_scalar_native((fletcher_4_ctx_t *)zcp, (char *)buf + p2size, size - p2size); } } void fletcher_4_native_varsize(const void *buf, uint64_t size, zio_cksum_t *zcp) { ZIO_SET_CHECKSUM(zcp, 0, 0, 0, 0); fletcher_4_scalar_native((fletcher_4_ctx_t *)zcp, buf, size); } static inline void fletcher_4_byteswap_impl(const void *buf, uint64_t size, zio_cksum_t *zcp) { fletcher_4_ctx_t ctx; const fletcher_4_ops_t *ops = fletcher_4_impl_get(); ops->init_byteswap(&ctx); ops->compute_byteswap(&ctx, buf, size); ops->fini_byteswap(&ctx, zcp); } /*ARGSUSED*/ void fletcher_4_byteswap(const void *buf, uint64_t size, const void *ctx_template, zio_cksum_t *zcp) { const uint64_t p2size = P2ALIGN(size, FLETCHER_MIN_SIMD_SIZE); ASSERT(IS_P2ALIGNED(size, sizeof (uint32_t))); if (size == 0 || p2size == 0) { ZIO_SET_CHECKSUM(zcp, 0, 0, 0, 0); if (size > 0) fletcher_4_scalar_byteswap((fletcher_4_ctx_t *)zcp, buf, size); } else { fletcher_4_byteswap_impl(buf, p2size, zcp); if (p2size < size) fletcher_4_scalar_byteswap((fletcher_4_ctx_t *)zcp, (char *)buf + p2size, size - p2size); } } /* Incremental Fletcher 4 */ #define ZFS_FLETCHER_4_INC_MAX_SIZE (8ULL << 20) static inline void fletcher_4_incremental_combine(zio_cksum_t *zcp, const uint64_t size, const zio_cksum_t *nzcp) { const uint64_t c1 = size / sizeof (uint32_t); const uint64_t c2 = c1 * (c1 + 1) / 2; const uint64_t c3 = c2 * (c1 + 2) / 3; /* * Value of 'c3' overflows on buffer sizes close to 16MiB. For that * reason we split incremental fletcher4 computation of large buffers * to steps of (ZFS_FLETCHER_4_INC_MAX_SIZE) size. */ ASSERT3U(size, <=, ZFS_FLETCHER_4_INC_MAX_SIZE); zcp->zc_word[3] += nzcp->zc_word[3] + c1 * zcp->zc_word[2] + c2 * zcp->zc_word[1] + c3 * zcp->zc_word[0]; zcp->zc_word[2] += nzcp->zc_word[2] + c1 * zcp->zc_word[1] + c2 * zcp->zc_word[0]; zcp->zc_word[1] += nzcp->zc_word[1] + c1 * zcp->zc_word[0]; zcp->zc_word[0] += nzcp->zc_word[0]; } static inline void fletcher_4_incremental_impl(boolean_t native, const void *buf, uint64_t size, zio_cksum_t *zcp) { while (size > 0) { zio_cksum_t nzc; uint64_t len = MIN(size, ZFS_FLETCHER_4_INC_MAX_SIZE); if (native) fletcher_4_native(buf, len, NULL, &nzc); else fletcher_4_byteswap(buf, len, NULL, &nzc); fletcher_4_incremental_combine(zcp, len, &nzc); size -= len; buf += len; } } int fletcher_4_incremental_native(void *buf, size_t size, void *data) { zio_cksum_t *zcp = data; /* Use scalar impl to directly update cksum of small blocks */ if (size < SPA_MINBLOCKSIZE) fletcher_4_scalar_native((fletcher_4_ctx_t *)zcp, buf, size); else fletcher_4_incremental_impl(B_TRUE, buf, size, zcp); return (0); } int fletcher_4_incremental_byteswap(void *buf, size_t size, void *data) { zio_cksum_t *zcp = data; /* Use scalar impl to directly update cksum of small blocks */ if (size < SPA_MINBLOCKSIZE) fletcher_4_scalar_byteswap((fletcher_4_ctx_t *)zcp, buf, size); else fletcher_4_incremental_impl(B_FALSE, buf, size, zcp); return (0); } #if defined(_KERNEL) /* * Fletcher 4 kstats */ static int fletcher_4_kstat_headers(char *buf, size_t size) { ssize_t off = 0; off += snprintf(buf + off, size, "%-17s", "implementation"); off += snprintf(buf + off, size - off, "%-15s", "native"); (void) snprintf(buf + off, size - off, "%-15s\n", "byteswap"); return (0); } static int fletcher_4_kstat_data(char *buf, size_t size, void *data) { struct fletcher_4_kstat *fastest_stat = &fletcher_4_stat_data[fletcher_4_supp_impls_cnt]; struct fletcher_4_kstat *curr_stat = (struct fletcher_4_kstat *)data; ssize_t off = 0; if (curr_stat == fastest_stat) { off += snprintf(buf + off, size - off, "%-17s", "fastest"); off += snprintf(buf + off, size - off, "%-15s", fletcher_4_supp_impls[fastest_stat->native]->name); off += snprintf(buf + off, size - off, "%-15s\n", fletcher_4_supp_impls[fastest_stat->byteswap]->name); } else { ptrdiff_t id = curr_stat - fletcher_4_stat_data; off += snprintf(buf + off, size - off, "%-17s", fletcher_4_supp_impls[id]->name); off += snprintf(buf + off, size - off, "%-15llu", (u_longlong_t)curr_stat->native); off += snprintf(buf + off, size - off, "%-15llu\n", (u_longlong_t)curr_stat->byteswap); } return (0); } static void * fletcher_4_kstat_addr(kstat_t *ksp, loff_t n) { if (n <= fletcher_4_supp_impls_cnt) ksp->ks_private = (void *) (fletcher_4_stat_data + n); else ksp->ks_private = NULL; return (ksp->ks_private); } #endif #define FLETCHER_4_FASTEST_FN_COPY(type, src) \ { \ fletcher_4_fastest_impl.init_ ## type = src->init_ ## type; \ fletcher_4_fastest_impl.fini_ ## type = src->fini_ ## type; \ fletcher_4_fastest_impl.compute_ ## type = src->compute_ ## type; \ } #define FLETCHER_4_BENCH_NS (MSEC2NSEC(1)) /* 1ms */ typedef void fletcher_checksum_func_t(const void *, uint64_t, const void *, zio_cksum_t *); #if defined(_KERNEL) static void fletcher_4_benchmark_impl(boolean_t native, char *data, uint64_t data_size) { struct fletcher_4_kstat *fastest_stat = &fletcher_4_stat_data[fletcher_4_supp_impls_cnt]; hrtime_t start; uint64_t run_bw, run_time_ns, best_run = 0; zio_cksum_t zc; uint32_t i, l, sel_save = IMPL_READ(fletcher_4_impl_chosen); fletcher_checksum_func_t *fletcher_4_test = native ? fletcher_4_native : fletcher_4_byteswap; for (i = 0; i < fletcher_4_supp_impls_cnt; i++) { struct fletcher_4_kstat *stat = &fletcher_4_stat_data[i]; uint64_t run_count = 0; /* temporary set an implementation */ fletcher_4_impl_chosen = i; kpreempt_disable(); start = gethrtime(); do { for (l = 0; l < 32; l++, run_count++) fletcher_4_test(data, data_size, NULL, &zc); run_time_ns = gethrtime() - start; } while (run_time_ns < FLETCHER_4_BENCH_NS); kpreempt_enable(); run_bw = data_size * run_count * NANOSEC; run_bw /= run_time_ns; /* B/s */ if (native) stat->native = run_bw; else stat->byteswap = run_bw; if (run_bw > best_run) { best_run = run_bw; if (native) { fastest_stat->native = i; FLETCHER_4_FASTEST_FN_COPY(native, fletcher_4_supp_impls[i]); } else { fastest_stat->byteswap = i; FLETCHER_4_FASTEST_FN_COPY(byteswap, fletcher_4_supp_impls[i]); } } } /* restore original selection */ atomic_swap_32(&fletcher_4_impl_chosen, sel_save); } #endif /* _KERNEL */ /* * Initialize and benchmark all supported implementations. */ static void fletcher_4_benchmark(void) { fletcher_4_ops_t *curr_impl; int i, c; /* Move supported implementations into fletcher_4_supp_impls */ for (i = 0, c = 0; i < ARRAY_SIZE(fletcher_4_impls); i++) { curr_impl = (fletcher_4_ops_t *)fletcher_4_impls[i]; if (curr_impl->valid && curr_impl->valid()) fletcher_4_supp_impls[c++] = curr_impl; } membar_producer(); /* complete fletcher_4_supp_impls[] init */ fletcher_4_supp_impls_cnt = c; /* number of supported impl */ #if defined(_KERNEL) static const size_t data_size = 1 << SPA_OLD_MAXBLOCKSHIFT; /* 128kiB */ char *databuf = vmem_alloc(data_size, KM_SLEEP); for (i = 0; i < data_size / sizeof (uint64_t); i++) ((uint64_t *)databuf)[i] = (uintptr_t)(databuf+i); /* warm-up */ fletcher_4_benchmark_impl(B_FALSE, databuf, data_size); fletcher_4_benchmark_impl(B_TRUE, databuf, data_size); vmem_free(databuf, data_size); #else /* * Skip the benchmark in user space to avoid impacting libzpool * consumers (zdb, zhack, zinject, ztest). The last implementation * is assumed to be the fastest and used by default. */ memcpy(&fletcher_4_fastest_impl, fletcher_4_supp_impls[fletcher_4_supp_impls_cnt - 1], sizeof (fletcher_4_fastest_impl)); fletcher_4_fastest_impl.name = "fastest"; membar_producer(); #endif /* _KERNEL */ } void fletcher_4_init(void) { /* Determine the fastest available implementation. */ fletcher_4_benchmark(); #if defined(_KERNEL) /* Install kstats for all implementations */ fletcher_4_kstat = kstat_create("zfs", 0, "fletcher_4_bench", "misc", KSTAT_TYPE_RAW, 0, KSTAT_FLAG_VIRTUAL); if (fletcher_4_kstat != NULL) { fletcher_4_kstat->ks_data = NULL; fletcher_4_kstat->ks_ndata = UINT32_MAX; kstat_set_raw_ops(fletcher_4_kstat, fletcher_4_kstat_headers, fletcher_4_kstat_data, fletcher_4_kstat_addr); kstat_install(fletcher_4_kstat); } #endif /* Finish initialization */ fletcher_4_initialized = B_TRUE; } void fletcher_4_fini(void) { #if defined(_KERNEL) if (fletcher_4_kstat != NULL) { kstat_delete(fletcher_4_kstat); fletcher_4_kstat = NULL; } #endif } /* ABD adapters */ static void abd_fletcher_4_init(zio_abd_checksum_data_t *cdp) { const fletcher_4_ops_t *ops = fletcher_4_impl_get(); cdp->acd_private = (void *) ops; if (cdp->acd_byteorder == ZIO_CHECKSUM_NATIVE) ops->init_native(cdp->acd_ctx); else ops->init_byteswap(cdp->acd_ctx); } static void abd_fletcher_4_fini(zio_abd_checksum_data_t *cdp) { fletcher_4_ops_t *ops = (fletcher_4_ops_t *)cdp->acd_private; ASSERT(ops); if (cdp->acd_byteorder == ZIO_CHECKSUM_NATIVE) ops->fini_native(cdp->acd_ctx, cdp->acd_zcp); else ops->fini_byteswap(cdp->acd_ctx, cdp->acd_zcp); } static void abd_fletcher_4_simd2scalar(boolean_t native, void *data, size_t size, zio_abd_checksum_data_t *cdp) { zio_cksum_t *zcp = cdp->acd_zcp; ASSERT3U(size, <, FLETCHER_MIN_SIMD_SIZE); abd_fletcher_4_fini(cdp); cdp->acd_private = (void *)&fletcher_4_scalar_ops; if (native) fletcher_4_incremental_native(data, size, zcp); else fletcher_4_incremental_byteswap(data, size, zcp); } static int abd_fletcher_4_iter(void *data, size_t size, void *private) { zio_abd_checksum_data_t *cdp = (zio_abd_checksum_data_t *)private; fletcher_4_ctx_t *ctx = cdp->acd_ctx; fletcher_4_ops_t *ops = (fletcher_4_ops_t *)cdp->acd_private; boolean_t native = cdp->acd_byteorder == ZIO_CHECKSUM_NATIVE; uint64_t asize = P2ALIGN(size, FLETCHER_MIN_SIMD_SIZE); ASSERT(IS_P2ALIGNED(size, sizeof (uint32_t))); if (asize > 0) { if (native) ops->compute_native(ctx, data, asize); else ops->compute_byteswap(ctx, data, asize); size -= asize; data = (char *)data + asize; } if (size > 0) { ASSERT3U(size, <, FLETCHER_MIN_SIMD_SIZE); /* At this point we have to switch to scalar impl */ abd_fletcher_4_simd2scalar(native, data, size, cdp); } return (0); } zio_abd_checksum_func_t fletcher_4_abd_ops = { .acf_init = abd_fletcher_4_init, .acf_fini = abd_fletcher_4_fini, .acf_iter = abd_fletcher_4_iter }; #if defined(_KERNEL) #define IMPL_FMT(impl, i) (((impl) == (i)) ? "[%s] " : "%s ") #if defined(__linux__) static int fletcher_4_param_get(char *buffer, zfs_kernel_param_t *unused) { const uint32_t impl = IMPL_READ(fletcher_4_impl_chosen); char *fmt; int cnt = 0; /* list fastest */ fmt = IMPL_FMT(impl, IMPL_FASTEST); cnt += sprintf(buffer + cnt, fmt, "fastest"); /* list all supported implementations */ for (uint32_t i = 0; i < fletcher_4_supp_impls_cnt; ++i) { fmt = IMPL_FMT(impl, i); cnt += sprintf(buffer + cnt, fmt, fletcher_4_supp_impls[i]->name); } return (cnt); } static int fletcher_4_param_set(const char *val, zfs_kernel_param_t *unused) { return (fletcher_4_impl_set(val)); } #else #include static int fletcher_4_param(ZFS_MODULE_PARAM_ARGS) { int err; if (req->newptr == NULL) { const uint32_t impl = IMPL_READ(fletcher_4_impl_chosen); const int init_buflen = 64; const char *fmt; struct sbuf *s; s = sbuf_new_for_sysctl(NULL, NULL, init_buflen, req); /* list fastest */ fmt = IMPL_FMT(impl, IMPL_FASTEST); (void) sbuf_printf(s, fmt, "fastest"); /* list all supported implementations */ for (uint32_t i = 0; i < fletcher_4_supp_impls_cnt; ++i) { fmt = IMPL_FMT(impl, i); (void) sbuf_printf(s, fmt, fletcher_4_supp_impls[i]->name); } err = sbuf_finish(s); sbuf_delete(s); return (err); } char buf[16]; err = sysctl_handle_string(oidp, buf, sizeof (buf), req); if (err) return (err); return (-fletcher_4_impl_set(buf)); } #endif #undef IMPL_FMT /* * Choose a fletcher 4 implementation in ZFS. * Users can choose "cycle" to exercise all implementations, but this is * for testing purpose therefore it can only be set in user space. */ /* BEGIN CSTYLED */ ZFS_MODULE_VIRTUAL_PARAM_CALL(zfs, zfs_, fletcher_4_impl, fletcher_4_param_set, fletcher_4_param_get, ZMOD_RW, "Select fletcher 4 implementation."); /* END CSTYLED */ EXPORT_SYMBOL(fletcher_init); EXPORT_SYMBOL(fletcher_2_incremental_native); EXPORT_SYMBOL(fletcher_2_incremental_byteswap); EXPORT_SYMBOL(fletcher_4_init); EXPORT_SYMBOL(fletcher_4_fini); EXPORT_SYMBOL(fletcher_2_native); EXPORT_SYMBOL(fletcher_2_byteswap); EXPORT_SYMBOL(fletcher_4_native); EXPORT_SYMBOL(fletcher_4_native_varsize); EXPORT_SYMBOL(fletcher_4_byteswap); EXPORT_SYMBOL(fletcher_4_incremental_native); EXPORT_SYMBOL(fletcher_4_incremental_byteswap); EXPORT_SYMBOL(fletcher_4_abd_ops); #endif