zfs-builds-mm/zfs-0.8.5/include/sys/vdev_raidz_impl.h
2020-10-22 13:48:46 +02:00

370 lines
9.7 KiB
C

/*
* 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 (C) 2016 Gvozden Nešković. All rights reserved.
*/
#ifndef _VDEV_RAIDZ_H
#define _VDEV_RAIDZ_H
#include <sys/types.h>
#include <sys/debug.h>
#include <sys/kstat.h>
#include <sys/abd.h>
#ifdef __cplusplus
extern "C" {
#endif
#define CODE_P (0U)
#define CODE_Q (1U)
#define CODE_R (2U)
#define PARITY_P (1U)
#define PARITY_PQ (2U)
#define PARITY_PQR (3U)
#define TARGET_X (0U)
#define TARGET_Y (1U)
#define TARGET_Z (2U)
/*
* Parity generation methods indexes
*/
enum raidz_math_gen_op {
RAIDZ_GEN_P = 0,
RAIDZ_GEN_PQ,
RAIDZ_GEN_PQR,
RAIDZ_GEN_NUM = 3
};
/*
* Data reconstruction methods indexes
*/
enum raidz_rec_op {
RAIDZ_REC_P = 0,
RAIDZ_REC_Q,
RAIDZ_REC_R,
RAIDZ_REC_PQ,
RAIDZ_REC_PR,
RAIDZ_REC_QR,
RAIDZ_REC_PQR,
RAIDZ_REC_NUM = 7
};
extern const char *raidz_gen_name[RAIDZ_GEN_NUM];
extern const char *raidz_rec_name[RAIDZ_REC_NUM];
/*
* Methods used to define raidz implementation
*
* @raidz_gen_f Parity generation function
* @par1 pointer to raidz_map
* @raidz_rec_f Data reconstruction function
* @par1 pointer to raidz_map
* @par2 array of reconstruction targets
* @will_work_f Function returns TRUE if impl. is supported on the system
* @init_impl_f Function is called once on init
* @fini_impl_f Function is called once on fini
*/
typedef void (*raidz_gen_f)(void *);
typedef int (*raidz_rec_f)(void *, const int *);
typedef boolean_t (*will_work_f)(void);
typedef void (*init_impl_f)(void);
typedef void (*fini_impl_f)(void);
#define RAIDZ_IMPL_NAME_MAX (16)
typedef struct raidz_impl_ops {
init_impl_f init;
fini_impl_f fini;
raidz_gen_f gen[RAIDZ_GEN_NUM]; /* Parity generate functions */
raidz_rec_f rec[RAIDZ_REC_NUM]; /* Data reconstruction functions */
will_work_f is_supported; /* Support check function */
char name[RAIDZ_IMPL_NAME_MAX]; /* Name of the implementation */
} raidz_impl_ops_t;
typedef struct raidz_col {
uint64_t rc_devidx; /* child device index for I/O */
uint64_t rc_offset; /* device offset */
uint64_t rc_size; /* I/O size */
abd_t *rc_abd; /* I/O data */
void *rc_gdata; /* used to store the "good" version */
int rc_error; /* I/O error for this device */
uint8_t rc_tried; /* Did we attempt this I/O column? */
uint8_t rc_skipped; /* Did we skip this I/O column? */
} raidz_col_t;
typedef struct raidz_map {
uint64_t rm_cols; /* Regular column count */
uint64_t rm_scols; /* Count including skipped columns */
uint64_t rm_bigcols; /* Number of oversized columns */
uint64_t rm_asize; /* Actual total I/O size */
uint64_t rm_missingdata; /* Count of missing data devices */
uint64_t rm_missingparity; /* Count of missing parity devices */
uint64_t rm_firstdatacol; /* First data column/parity count */
uint64_t rm_nskip; /* Skipped sectors for padding */
uint64_t rm_skipstart; /* Column index of padding start */
abd_t *rm_abd_copy; /* rm_asize-buffer of copied data */
uintptr_t rm_reports; /* # of referencing checksum reports */
uint8_t rm_freed; /* map no longer has referencing ZIO */
uint8_t rm_ecksuminjected; /* checksum error was injected */
const raidz_impl_ops_t *rm_ops; /* RAIDZ math operations */
raidz_col_t rm_col[1]; /* Flexible array of I/O columns */
} raidz_map_t;
#define RAIDZ_ORIGINAL_IMPL (INT_MAX)
extern const raidz_impl_ops_t vdev_raidz_scalar_impl;
#if defined(__x86_64) && defined(HAVE_SSE2) /* only x86_64 for now */
extern const raidz_impl_ops_t vdev_raidz_sse2_impl;
#endif
#if defined(__x86_64) && defined(HAVE_SSSE3) /* only x86_64 for now */
extern const raidz_impl_ops_t vdev_raidz_ssse3_impl;
#endif
#if defined(__x86_64) && defined(HAVE_AVX2) /* only x86_64 for now */
extern const raidz_impl_ops_t vdev_raidz_avx2_impl;
#endif
#if defined(__x86_64) && defined(HAVE_AVX512F) /* only x86_64 for now */
extern const raidz_impl_ops_t vdev_raidz_avx512f_impl;
#endif
#if defined(__x86_64) && defined(HAVE_AVX512BW) /* only x86_64 for now */
extern const raidz_impl_ops_t vdev_raidz_avx512bw_impl;
#endif
#if defined(__aarch64__)
extern const raidz_impl_ops_t vdev_raidz_aarch64_neon_impl;
extern const raidz_impl_ops_t vdev_raidz_aarch64_neonx2_impl;
#endif
/*
* Commonly used raidz_map helpers
*
* raidz_parity Returns parity of the RAIDZ block
* raidz_ncols Returns number of columns the block spans
* raidz_nbigcols Returns number of big columns
* raidz_col_p Returns pointer to a column
* raidz_col_size Returns size of a column
* raidz_big_size Returns size of big columns
* raidz_short_size Returns size of short columns
*/
#define raidz_parity(rm) ((rm)->rm_firstdatacol)
#define raidz_ncols(rm) ((rm)->rm_cols)
#define raidz_nbigcols(rm) ((rm)->rm_bigcols)
#define raidz_col_p(rm, c) ((rm)->rm_col + (c))
#define raidz_col_size(rm, c) ((rm)->rm_col[c].rc_size)
#define raidz_big_size(rm) (raidz_col_size(rm, CODE_P))
#define raidz_short_size(rm) (raidz_col_size(rm, raidz_ncols(rm)-1))
/*
* Macro defines an RAIDZ parity generation method
*
* @code parity the function produce
* @impl name of the implementation
*/
#define _RAIDZ_GEN_WRAP(code, impl) \
static void \
impl ## _gen_ ## code(void *rmp) \
{ \
raidz_map_t *rm = (raidz_map_t *)rmp; \
raidz_generate_## code ## _impl(rm); \
}
/*
* Macro defines an RAIDZ data reconstruction method
*
* @code parity the function produce
* @impl name of the implementation
*/
#define _RAIDZ_REC_WRAP(code, impl) \
static int \
impl ## _rec_ ## code(void *rmp, const int *tgtidx) \
{ \
raidz_map_t *rm = (raidz_map_t *)rmp; \
return (raidz_reconstruct_## code ## _impl(rm, tgtidx)); \
}
/*
* Define all gen methods for an implementation
*
* @impl name of the implementation
*/
#define DEFINE_GEN_METHODS(impl) \
_RAIDZ_GEN_WRAP(p, impl); \
_RAIDZ_GEN_WRAP(pq, impl); \
_RAIDZ_GEN_WRAP(pqr, impl)
/*
* Define all rec functions for an implementation
*
* @impl name of the implementation
*/
#define DEFINE_REC_METHODS(impl) \
_RAIDZ_REC_WRAP(p, impl); \
_RAIDZ_REC_WRAP(q, impl); \
_RAIDZ_REC_WRAP(r, impl); \
_RAIDZ_REC_WRAP(pq, impl); \
_RAIDZ_REC_WRAP(pr, impl); \
_RAIDZ_REC_WRAP(qr, impl); \
_RAIDZ_REC_WRAP(pqr, impl)
#define RAIDZ_GEN_METHODS(impl) \
{ \
[RAIDZ_GEN_P] = & impl ## _gen_p, \
[RAIDZ_GEN_PQ] = & impl ## _gen_pq, \
[RAIDZ_GEN_PQR] = & impl ## _gen_pqr \
}
#define RAIDZ_REC_METHODS(impl) \
{ \
[RAIDZ_REC_P] = & impl ## _rec_p, \
[RAIDZ_REC_Q] = & impl ## _rec_q, \
[RAIDZ_REC_R] = & impl ## _rec_r, \
[RAIDZ_REC_PQ] = & impl ## _rec_pq, \
[RAIDZ_REC_PR] = & impl ## _rec_pr, \
[RAIDZ_REC_QR] = & impl ## _rec_qr, \
[RAIDZ_REC_PQR] = & impl ## _rec_pqr \
}
typedef struct raidz_impl_kstat {
uint64_t gen[RAIDZ_GEN_NUM]; /* gen method speed B/s */
uint64_t rec[RAIDZ_REC_NUM]; /* rec method speed B/s */
} raidz_impl_kstat_t;
/*
* Enumerate various multiplication constants
* used in reconstruction methods
*/
typedef enum raidz_mul_info {
/* Reconstruct Q */
MUL_Q_X = 0,
/* Reconstruct R */
MUL_R_X = 0,
/* Reconstruct PQ */
MUL_PQ_X = 0,
MUL_PQ_Y = 1,
/* Reconstruct PR */
MUL_PR_X = 0,
MUL_PR_Y = 1,
/* Reconstruct QR */
MUL_QR_XQ = 0,
MUL_QR_X = 1,
MUL_QR_YQ = 2,
MUL_QR_Y = 3,
/* Reconstruct PQR */
MUL_PQR_XP = 0,
MUL_PQR_XQ = 1,
MUL_PQR_XR = 2,
MUL_PQR_YU = 3,
MUL_PQR_YP = 4,
MUL_PQR_YQ = 5,
MUL_CNT = 6
} raidz_mul_info_t;
/*
* Powers of 2 in the Galois field.
*/
extern const uint8_t vdev_raidz_pow2[256] __attribute__((aligned(256)));
/* Logs of 2 in the Galois field defined above. */
extern const uint8_t vdev_raidz_log2[256] __attribute__((aligned(256)));
/*
* Multiply a given number by 2 raised to the given power.
*/
static inline uint8_t
vdev_raidz_exp2(const uint8_t a, const unsigned exp)
{
if (a == 0)
return (0);
return (vdev_raidz_pow2[(exp + (unsigned)vdev_raidz_log2[a]) % 255]);
}
/*
* Galois Field operations.
*
* gf_exp2 - computes 2 raised to the given power
* gf_exp2 - computes 4 raised to the given power
* gf_mul - multiplication
* gf_div - division
* gf_inv - multiplicative inverse
*/
typedef unsigned gf_t;
typedef unsigned gf_log_t;
static inline gf_t
gf_mul(const gf_t a, const gf_t b)
{
gf_log_t logsum;
if (a == 0 || b == 0)
return (0);
logsum = (gf_log_t)vdev_raidz_log2[a] + (gf_log_t)vdev_raidz_log2[b];
return ((gf_t)vdev_raidz_pow2[logsum % 255]);
}
static inline gf_t
gf_div(const gf_t a, const gf_t b)
{
gf_log_t logsum;
ASSERT3U(b, >, 0);
if (a == 0)
return (0);
logsum = (gf_log_t)255 + (gf_log_t)vdev_raidz_log2[a] -
(gf_log_t)vdev_raidz_log2[b];
return ((gf_t)vdev_raidz_pow2[logsum % 255]);
}
static inline gf_t
gf_inv(const gf_t a)
{
gf_log_t logsum;
ASSERT3U(a, >, 0);
logsum = (gf_log_t)255 - (gf_log_t)vdev_raidz_log2[a];
return ((gf_t)vdev_raidz_pow2[logsum]);
}
static inline gf_t
gf_exp2(gf_log_t exp)
{
return (vdev_raidz_pow2[exp % 255]);
}
static inline gf_t
gf_exp4(gf_log_t exp)
{
ASSERT3U(exp, <=, 255);
return ((gf_t)vdev_raidz_pow2[(2 * exp) % 255]);
}
#ifdef __cplusplus
}
#endif
#endif /* _VDEV_RAIDZ_H */