liberasurecode/src/backends/jerasure/jerasure_rs_cauchy.c

477 lines
17 KiB
C

/*
* Copyright 2014 Kevin M Greenan
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice, this
* list of conditions and the following disclaimer in the documentation and/or
* other materials provided with the distribution. THIS SOFTWARE IS PROVIDED BY
* THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
* EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
* OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* jerasure_rs_cauchy backend implementation
*
* vi: set noai tw=79 ts=4 sw=4:
*/
#include <stdio.h>
#include <stdlib.h>
#include "erasurecode.h"
#include "erasurecode_backend.h"
#include "erasurecode_helpers.h"
#include "erasurecode_helpers_ext.h"
#define JERASURE_RS_CAUCHY_LIB_MAJOR 2
#define JERASURE_RS_CAUCHY_LIB_MINOR 0
#define JERASURE_RS_CAUCHY_LIB_REV 0
#define JERASURE_RS_CAUCHY_LIB_VER_STR "2.0"
#define JERASURE_RS_CAUCHY_LIB_NAME "jerasure_rs_cauchy"
#if defined(__MACOS__) || defined(__MACOSX__) || defined(__OSX__) || defined(__APPLE__)
#define JERASURE_RS_CAUCHY_SO_NAME "libJerasure.dylib"
#else
#define JERASURE_RS_CAUCHY_SO_NAME "libJerasure.so.2"
#endif
/* Forward declarations */
struct ec_backend_op_stubs jerasure_rs_cauchy_ops;
struct ec_backend jerasure_rs_cauchy;
struct ec_backend_common backend_jerasure_rs_cauchy;
typedef int* (*cauchy_original_coding_matrix_func)(int, int, int);
typedef int* (*jerasure_matrix_to_bitmatrix_func)(int, int, int, int *);
typedef int** (*jerasure_smart_bitmatrix_to_schedule_func)
(int, int, int, int *);
typedef void (*jerasure_bitmatrix_encode_func)
(int, int, int, int *, char **, char **, int, int);
typedef int (*jerasure_bitmatrix_decode_func)
(int, int, int, int *, int, int *,char **, char **, int, int);
typedef int * (*jerasure_erasures_to_erased_func)(int, int, int *);
typedef int (*jerasure_make_decoding_bitmatrix_func)
(int, int, int, int *, int *, int *, int *);
typedef void (*jerasure_bitmatrix_dotprod_func)
(int, int, int *, int *, int,char **, char **, int, int);
typedef void (*galois_uninit_field_func)(int);
/*
* ToDo (KMG): Should we make this a parameter, or is that
* exposing too much b.s. to the client?
*/
#define PYECC_CAUCHY_PACKETSIZE sizeof(long) * 128
struct jerasure_rs_cauchy_descriptor {
/* calls required for init */
cauchy_original_coding_matrix_func cauchy_original_coding_matrix;
jerasure_matrix_to_bitmatrix_func jerasure_matrix_to_bitmatrix;
jerasure_smart_bitmatrix_to_schedule_func jerasure_smart_bitmatrix_to_schedule;
/* calls required for free */
galois_uninit_field_func galois_uninit_field;
/* calls required for encode */
jerasure_bitmatrix_encode_func jerasure_bitmatrix_encode;
/* calls required for decode */
jerasure_bitmatrix_decode_func jerasure_bitmatrix_decode;
/* calls required for reconstruct */
jerasure_erasures_to_erased_func jerasure_erasures_to_erased;
jerasure_make_decoding_bitmatrix_func jerasure_make_decoding_bitmatrix;
jerasure_bitmatrix_dotprod_func jerasure_bitmatrix_dotprod;
/* fields needed to hold state */
int *matrix;
int *bitmatrix;
int **schedule;
int k;
int m;
int w;
};
static void free_rs_cauchy_desc(
struct jerasure_rs_cauchy_descriptor *jerasure_desc );
static int jerasure_rs_cauchy_encode(void *desc, char **data, char **parity,
int blocksize)
{
struct jerasure_rs_cauchy_descriptor *jerasure_desc =
(struct jerasure_rs_cauchy_descriptor*) desc;
/* FIXME - make jerasure_bitmatrix_encode return a value */
jerasure_desc->jerasure_bitmatrix_encode(jerasure_desc->k, jerasure_desc->m,
jerasure_desc->w, jerasure_desc->bitmatrix,
data, parity, blocksize,
PYECC_CAUCHY_PACKETSIZE);
return 0;
}
static int jerasure_rs_cauchy_decode(void *desc, char **data, char **parity,
int *missing_idxs, int blocksize)
{
struct jerasure_rs_cauchy_descriptor *jerasure_desc =
(struct jerasure_rs_cauchy_descriptor*)desc;
return jerasure_desc->jerasure_bitmatrix_decode(jerasure_desc->k,
jerasure_desc->m,
jerasure_desc->w,
jerasure_desc->bitmatrix,
0,
missing_idxs,
data,
parity,
blocksize,
PYECC_CAUCHY_PACKETSIZE);
}
static int jerasure_rs_cauchy_reconstruct(void *desc, char **data, char **parity,
int *missing_idxs, int destination_idx, int blocksize)
{
int k, m, w; /* erasure code paramters */
int ret = 0; /* return code */
int *decoding_row = NULL; /* decoding matrix row for decode */
int *erased = NULL; /* k+m length list of erased frag ids */
int *dm_ids = NULL; /* k length list of fragment ids */
int *decoding_matrix = NULL; /* matrix for decoding */
struct jerasure_rs_cauchy_descriptor *jerasure_desc =
(struct jerasure_rs_cauchy_descriptor*) desc;
k = jerasure_desc->k;
m = jerasure_desc->m;
w = jerasure_desc->w;
if (destination_idx < k) {
dm_ids = (int *) alloc_zeroed_buffer(sizeof(int) * k);
decoding_matrix = (int *) alloc_zeroed_buffer(sizeof(int *) * k * k * w * w);
erased = jerasure_desc->jerasure_erasures_to_erased(k, m, missing_idxs);
if (NULL == decoding_matrix || NULL == dm_ids || NULL == erased) {
goto out;
}
ret = jerasure_desc->jerasure_make_decoding_bitmatrix(k, m, w,
jerasure_desc->bitmatrix,
erased, decoding_matrix, dm_ids);
if (ret == 0) {
decoding_row = decoding_matrix + (destination_idx * k * w * w);
jerasure_desc->jerasure_bitmatrix_dotprod(jerasure_desc->k, jerasure_desc->w,
decoding_row, dm_ids, destination_idx,
data, parity, blocksize, PYECC_CAUCHY_PACKETSIZE);
} else {
/*
* ToDo (KMG) I know this is not needed, but keeping to prevent future
* memory leaks, as this function will be better optimized for decoding
* missing parity
*/
goto out;
}
} else {
/*
* If it is parity we are reconstructing, then just call decode.
* ToDo (KMG): We can do better than this, but this should perform just
* fine for most cases. We can adjust the decoding matrix like we
* did with ISA-L.
*/
jerasure_desc->jerasure_bitmatrix_decode(k, m, w,
jerasure_desc->bitmatrix,
0,
missing_idxs,
data,
parity,
blocksize,
PYECC_CAUCHY_PACKETSIZE);
}
out:
free(erased);
free(decoding_matrix);
free(dm_ids);
return ret;
}
/*
* Caller will allocate an array of size k for fragments_needed
*
*/
static int jerasure_rs_cauchy_min_fragments(void *desc, int *missing_idxs,
int *fragments_to_exclude, int *fragments_needed)
{
struct jerasure_rs_cauchy_descriptor *jerasure_desc =
(struct jerasure_rs_cauchy_descriptor*)desc;
uint64_t exclude_bm = convert_list_to_bitmap(fragments_to_exclude);
uint64_t missing_bm = convert_list_to_bitmap(missing_idxs) | exclude_bm;
int i;
int j = 0;
int ret = -1;
for (i = 0; i < (jerasure_desc->k + jerasure_desc->m); i++) {
if (!(missing_bm & (1 << i))) {
fragments_needed[j] = i;
j++;
}
if (j == jerasure_desc->k) {
ret = 0;
fragments_needed[j] = -1;
break;
}
}
return ret;
}
#define DEFAULT_W 4
static void * jerasure_rs_cauchy_init(struct ec_backend_args *args,
void *backend_sohandle)
{
struct jerasure_rs_cauchy_descriptor *desc = NULL;
int k, m, w;
desc = (struct jerasure_rs_cauchy_descriptor *)
malloc(sizeof(struct jerasure_rs_cauchy_descriptor));
if (NULL == desc) {
return NULL;
}
/* validate the base EC arguments */
k = args->uargs.k;
m = args->uargs.m;
if (args->uargs.w <= 0)
args->uargs.w = DEFAULT_W;
w = args->uargs.w;
/* store the base EC arguments in the descriptor */
desc->k = k;
desc->m = m;
desc->w = w;
/* validate EC arguments */
{
long long max_symbols;
max_symbols = 1LL << w;
if ((k + m) > max_symbols) {
goto error;
}
}
/*
* ISO C forbids casting a void* to a function pointer.
* Since dlsym return returns a void*, we use this union to
* "transform" the void* to a function pointer.
*/
union {
cauchy_original_coding_matrix_func initp;
jerasure_matrix_to_bitmatrix_func matrixtobitmatrixp;
jerasure_smart_bitmatrix_to_schedule_func matrixschedulep;
galois_uninit_field_func uninitp;
jerasure_bitmatrix_encode_func encodep;
jerasure_bitmatrix_decode_func decodep;
jerasure_erasures_to_erased_func erasedp;
jerasure_make_decoding_bitmatrix_func decodematrixp;
jerasure_bitmatrix_dotprod_func dotprodp;
void *vptr;
} func_handle = {.vptr = NULL};
/* fill in function addresses */
func_handle.vptr = NULL;
func_handle.vptr = dlsym(backend_sohandle, "jerasure_bitmatrix_encode");
desc->jerasure_bitmatrix_encode = func_handle.encodep;
if (NULL == desc->jerasure_bitmatrix_encode) {
goto error;
}
func_handle.vptr = NULL;
func_handle.vptr = dlsym(backend_sohandle, "jerasure_bitmatrix_decode");
desc->jerasure_bitmatrix_decode = func_handle.decodep;
if (NULL == desc->jerasure_bitmatrix_decode) {
goto error;
}
func_handle.vptr = NULL;
func_handle.vptr = dlsym(backend_sohandle, "cauchy_original_coding_matrix");
desc->cauchy_original_coding_matrix = func_handle.initp;
if (NULL == desc->cauchy_original_coding_matrix) {
goto error;
}
func_handle.vptr = NULL;
func_handle.vptr = dlsym(backend_sohandle, "jerasure_matrix_to_bitmatrix");
desc->jerasure_matrix_to_bitmatrix = func_handle.matrixtobitmatrixp;
if (NULL == desc->jerasure_matrix_to_bitmatrix) {
goto error;
}
func_handle.vptr = NULL;
func_handle.vptr = dlsym(backend_sohandle, "jerasure_smart_bitmatrix_to_schedule");
desc->jerasure_smart_bitmatrix_to_schedule = func_handle.matrixschedulep;
if (NULL == desc->jerasure_smart_bitmatrix_to_schedule) {
goto error;
}
func_handle.vptr = NULL;
func_handle.vptr = dlsym(backend_sohandle, "jerasure_make_decoding_bitmatrix");
desc->jerasure_make_decoding_bitmatrix = func_handle.decodematrixp;
if (NULL == desc->jerasure_make_decoding_bitmatrix) {
goto error;
}
func_handle.vptr = NULL;
func_handle.vptr = dlsym(backend_sohandle, "jerasure_bitmatrix_dotprod");
desc->jerasure_bitmatrix_dotprod = func_handle.dotprodp;
if (NULL == desc->jerasure_bitmatrix_dotprod) {
goto error;
}
func_handle.vptr = NULL;
func_handle.vptr = dlsym(backend_sohandle, "jerasure_erasures_to_erased");
desc->jerasure_erasures_to_erased = func_handle.erasedp;
if (NULL == desc->jerasure_erasures_to_erased) {
goto error;
}
func_handle.vptr = NULL;
func_handle.vptr = dlsym(backend_sohandle, "galois_uninit_field");
desc->galois_uninit_field = func_handle.uninitp;
if (NULL == desc->galois_uninit_field) {
goto error;
}
/* setup the Cauchy matrices and schedules */
desc->matrix = desc->cauchy_original_coding_matrix(k, m, w);
if (NULL == desc->matrix) {
goto error;
}
desc->bitmatrix = desc->jerasure_matrix_to_bitmatrix(k, m, w, desc->matrix);
if (NULL == desc->bitmatrix) {
goto bitmatrix_error;
}
desc->schedule = desc->jerasure_smart_bitmatrix_to_schedule(k, m, w, desc->bitmatrix);
if (NULL == desc->schedule) {
goto schedule_error;
}
return desc;
schedule_error:
free(desc->bitmatrix);
bitmatrix_error:
free(desc->matrix);
error:
free(desc);
return NULL;
}
/**
* Return the element-size, which is the number of bits stored
* on a given device, per codeword.
*
* Returns the size in bits!
*/
static int
jerasure_rs_cauchy_element_size(void* desc)
{
struct jerasure_rs_cauchy_descriptor *jerasure_desc =
(struct jerasure_rs_cauchy_descriptor*)desc;
return jerasure_desc->w * PYECC_CAUCHY_PACKETSIZE * 8;
}
static void free_rs_cauchy_desc(
struct jerasure_rs_cauchy_descriptor *jerasure_desc )
{
int i = 0;
int **schedule = NULL;
bool end_of_array = false;
if (jerasure_desc == NULL) {
return;
}
/*
* jerasure allocates some internal data structures for caching
* fields. It will allocate one for w, and if we do anything that
* needs to xor a region >= 16 bytes, it will also allocate one
* for 32. Fortunately we can safely uninit any value; if it
* wasn't inited it will be ignored.
*/
jerasure_desc->galois_uninit_field(jerasure_desc->w);
jerasure_desc->galois_uninit_field(32);
free(jerasure_desc->matrix);
free(jerasure_desc->bitmatrix);
// NOTE, based on an inspection of the jerasure code used to build the
// the schedule array, it appears that the sentinal used to signal the end
// of the array is a value of -1 in the first int field in the dereferenced
// value. We use this determine when to stop free-ing elements. See the
// jerasure_smart_bitmatrix_to_schedule and
// jerasure_dumb_bitmatrix_to_schedule functions in jerasure.c for the
// details.
schedule = jerasure_desc->schedule;
if (schedule != NULL) {
while (!end_of_array) {
if (schedule[i] == NULL || schedule[i][0] == -1) {
end_of_array = true;
}
free(schedule[i]);
i++;
}
}
free(schedule);
free(jerasure_desc);
}
static int jerasure_rs_cauchy_exit(void *desc)
{
struct jerasure_rs_cauchy_descriptor *jerasure_desc =
(struct jerasure_rs_cauchy_descriptor*)desc;
free_rs_cauchy_desc(jerasure_desc);
return 0;
}
/*
* For the time being, we only claim compatibility with versions that
* match exactly
*/
static bool jerasure_rs_cauchy_is_compatible_with(uint32_t version) {
return version == backend_jerasure_rs_cauchy.ec_backend_version;
}
struct ec_backend_op_stubs jerasure_rs_cauchy_op_stubs = {
.INIT = jerasure_rs_cauchy_init,
.EXIT = jerasure_rs_cauchy_exit,
.ENCODE = jerasure_rs_cauchy_encode,
.DECODE = jerasure_rs_cauchy_decode,
.FRAGSNEEDED = jerasure_rs_cauchy_min_fragments,
.RECONSTRUCT = jerasure_rs_cauchy_reconstruct,
.ELEMENTSIZE = jerasure_rs_cauchy_element_size,
.ISCOMPATIBLEWITH = jerasure_rs_cauchy_is_compatible_with,
.GETMETADATASIZE = get_backend_metadata_size_zero,
.GETENCODEOFFSET = get_encode_offset_zero,
};
struct ec_backend_common backend_jerasure_rs_cauchy = {
.id = EC_BACKEND_JERASURE_RS_CAUCHY,
.name = JERASURE_RS_CAUCHY_LIB_NAME,
.soname = JERASURE_RS_CAUCHY_SO_NAME,
.soversion = JERASURE_RS_CAUCHY_LIB_VER_STR,
.ops = &jerasure_rs_cauchy_op_stubs,
.ec_backend_version = _VERSION(JERASURE_RS_CAUCHY_LIB_MAJOR,
JERASURE_RS_CAUCHY_LIB_MINOR,
JERASURE_RS_CAUCHY_LIB_REV),
};