Merge "ISA-L Cauchy support"

5 files changed, 643 insertions, 545 deletions

diff --git a/src/Makefile.am b/src/Makefile.am
index 2566f74..eb2f89f 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -6,6 +6,7 @@ INCLUDES = \
 		-I$(top_srcdir)/include/erasurecode \
 		-I$(top_srcdir)/include/xor_codes \
 		-I$(top_srcdir)/include/rs_vand \
+		-I$(top_srcdir)/include/isa_l \
 		-I$(top_srcdir)/include/shss
 
 # liberasurecode params
@@ -20,7 +21,9 @@ liberasurecode_la_SOURCES = \
 		backends/xor/flat_xor_hd.c \
 		backends/jerasure/jerasure_rs_vand.c \
 		backends/jerasure/jerasure_rs_cauchy.c \
+		backends/isa-l/isa_l_common.c \
 		backends/isa-l/isa_l_rs_vand.c \
+		backends/isa-l/isa_l_rs_cauchy.c \
 		backends/rs_vand/liberasurecode_rs_vand.c \
 		builtin/rs_vand/rs_galois.c \
 		backends/shss/shss.c
diff --git a/src/backends/isa-l/isa_l_common.c b/src/backends/isa-l/isa_l_common.c
new file mode 100644
index 0000000..07deb13
--- /dev/null
+++ b/src/backends/isa-l/isa_l_common.c
@@ -0,0 +1,544 @@
+/*
+ * Copyright 2014 Kevin M Greenan
+ * Copyright 2014 Tushar Gohad
+ *
+ * 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.
+ *
+ * isa_l_rs_vand 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"
+#include "isa_l_common.h"
+
+int isa_l_encode(void *desc, char **data, char **parity,
+        int blocksize)
+{
+    isa_l_descriptor *isa_l_desc = (isa_l_descriptor*) desc;
+
+    unsigned char *g_tbls = NULL;
+    int k = isa_l_desc->k;
+    int m = isa_l_desc->m;
+
+    // Generate g_tbls from encode matrix encode_matrix
+    g_tbls = malloc(sizeof(unsigned char) * (k * m * 32));
+    if (NULL == g_tbls) {
+        return -1;
+    }
+
+    isa_l_desc->ec_init_tables(k, m, &isa_l_desc->matrix[k * k], g_tbls);
+
+    /* FIXME - make ec_encode_data return a value */
+    isa_l_desc->ec_encode_data(blocksize, k, m, g_tbls, (unsigned char**)data,
+                               (unsigned char**)parity);
+    free(g_tbls);
+    return 0;
+}
+
+static unsigned char* isa_l_get_decode_matrix(int k, int m, unsigned char *encode_matrix, int *missing_idxs)
+{
+    int i = 0, j = 0, l = 0;
+    int n = k + m;
+    unsigned char *decode_matrix = malloc(sizeof(unsigned char) * k * k);
+    uint64_t missing_bm = convert_list_to_bitmap(missing_idxs);
+
+    while (i < k && l < n) {
+        if (((1 << l) & missing_bm) == 0) {
+            for (j = 0; j < k; j++) {
+                decode_matrix[(k * i) + j] = encode_matrix[(k * l) + j];
+            }
+            i++;
+        }
+        l++;
+    }
+
+    if (i != k) {
+        free(decode_matrix);
+        decode_matrix = NULL;
+    }
+
+    return decode_matrix;
+}
+
+static int get_num_missing_elements(int *missing_idxs)
+{
+    int i = 0;
+
+    while (missing_idxs[i] > -1) {
+        i++;
+    }
+
+    return i;
+}
+
+static void mult_and_xor_row(unsigned char *to_row,
+                             unsigned char *from_row,
+                             unsigned char val,
+                             int num_elems,
+                             gf_mul_func gf_mul)
+{
+    int i;
+
+    for (i = 0; i < num_elems; i++) {
+        to_row[i] ^= gf_mul(val, from_row[i]);
+    }
+}
+
+/*
+ * TODO: Add in missing parity rows and adjust the inverse_rows to
+ * be used for parity.
+ */
+static unsigned char* get_inverse_rows(int k,
+                                       int m,
+                                       unsigned char *decode_inverse,
+                                       unsigned char* encode_matrix,
+                                       int *missing_idxs,
+                                       gf_mul_func gf_mul)
+{
+    uint64_t missing_bm = convert_list_to_bitmap(missing_idxs);
+    int num_missing_elements = get_num_missing_elements(missing_idxs);
+    unsigned char *inverse_rows = (unsigned char*)malloc(sizeof(unsigned
+                                    char*) * k * num_missing_elements);
+    int i, j, l = 0;
+    int n = k + m;
+
+    if (NULL == inverse_rows) {
+        return NULL;
+    }
+
+    memset(inverse_rows, 0, sizeof(unsigned
+                                    char*) * k * num_missing_elements);
+
+    /*
+     * Fill in rows for missing data
+     */
+    for (i = 0; i < k; i++) {
+        if ((1 << i) & missing_bm) {
+            for (j = 0; j < k; j++) {
+                inverse_rows[(l * k) + j] = decode_inverse[(i * k) + j];
+            }
+            l++;
+        }
+    }
+
+    /*
+     * Process missing parity.
+     *
+     * Start with an all-zero row.
+     *
+     * For each data element, if the data element is:
+     *
+     * Available: XOR the corresponding coefficient from the
+     * encoding matrix.
+     *
+     * Unavailable: multiply corresponding coefficient with
+     * the row that corresponds to the missing data in inverse_rows
+     * and XOR the resulting row with this row.
+     */
+    for (i = k; i < n; i++) {
+        // Parity is missing
+        if ((1 << i) & missing_bm) {
+            int d_idx_avail = 0;
+            int d_idx_unavail = 0;
+            for (j = 0; j < k; j++) {
+                // This data is available, so we can use the encode matrix
+                if (((1 << j) & missing_bm) == 0) {
+                    inverse_rows[(l * k) + d_idx_avail] ^= encode_matrix[(i * k) + j];
+                    d_idx_avail++;
+                } else {
+                    mult_and_xor_row(&inverse_rows[l * k],
+                                     &inverse_rows[d_idx_unavail * k],
+                                     encode_matrix[(i * k) + j],
+                                     k,
+                                     gf_mul);
+                    d_idx_unavail++;
+                }
+            }
+            l++;
+        }
+    }
+    return inverse_rows;
+}
+
+int isa_l_decode(void *desc, char **data, char **parity,
+        int *missing_idxs, int blocksize)
+{
+    isa_l_descriptor *isa_l_desc = (isa_l_descriptor*)desc;
+
+    unsigned char *g_tbls = NULL;
+    unsigned char *decode_matrix = NULL;
+    unsigned char *decode_inverse = NULL;
+    unsigned char *inverse_rows = NULL;
+    unsigned char **decoded_elements = NULL;
+    unsigned char **available_fragments = NULL;
+    int k = isa_l_desc->k;
+    int m = isa_l_desc->m;
+    int n = k + m;
+    int ret = -1;
+    int i, j;
+
+    int num_missing_elements = get_num_missing_elements(missing_idxs);
+    uint64_t missing_bm = convert_list_to_bitmap(missing_idxs);
+
+    decode_matrix = isa_l_get_decode_matrix(k, m, isa_l_desc->matrix, missing_idxs);
+
+    if (NULL == decode_matrix) {
+        goto out;
+    }
+
+    decode_inverse = (unsigned char*)malloc(sizeof(unsigned char) * k * k);
+
+    if (NULL == decode_inverse) {
+        goto out;
+    }
+
+    int im_ret = isa_l_desc->gf_invert_matrix(decode_matrix, decode_inverse, k);
+    if (im_ret < 0) {
+        goto out;
+    }
+
+    // Generate g_tbls from computed decode matrix (k x k) matrix
+    g_tbls = malloc(sizeof(unsigned char) * (k * m * 32));
+    if (NULL == g_tbls) {
+        goto out;
+    }
+
+    inverse_rows = get_inverse_rows(k, m, decode_inverse, isa_l_desc->matrix, missing_idxs, isa_l_desc->gf_mul);
+
+    decoded_elements = (unsigned char**)malloc(sizeof(unsigned char*)*num_missing_elements);
+    if (NULL == decoded_elements) {
+        goto out;
+    }
+
+    available_fragments = (unsigned char**)malloc(sizeof(unsigned char*)*k);
+    if (NULL == available_fragments) {
+        goto out;
+    }
+
+    j = 0;
+    for (i = 0; i < n; i++) {
+        if (missing_bm & (1 << i)) {
+            continue;
+        }
+        if (j == k) {
+            break;
+        }
+        if (i < k) {
+            available_fragments[j] = (unsigned char*)data[i];
+        } else {
+            available_fragments[j] = (unsigned char*)parity[i-k];
+        }
+        j++;
+    }
+
+    // Grab pointers to memory needed for missing data fragments
+    j = 0;
+    for (i = 0; i < k; i++) {
+        if (missing_bm & (1 << i)) {
+            decoded_elements[j] = (unsigned char*)data[i];
+            j++;
+        }
+    }
+    for (i = k; i < n; i++) {
+        if (missing_bm & (1 << i)) {
+            decoded_elements[j] = (unsigned char*)parity[i - k];
+            j++;
+        }
+    }
+
+    isa_l_desc->ec_init_tables(k, num_missing_elements, inverse_rows, g_tbls);
+
+    isa_l_desc->ec_encode_data(blocksize, k, num_missing_elements, g_tbls, (unsigned char**)available_fragments,
+                               (unsigned char**)decoded_elements);
+
+    ret = 0;
+
+out:
+    free(g_tbls);
+    free(decode_matrix);
+    free(decode_inverse);
+    free(inverse_rows);
+    free(decoded_elements);
+    free(available_fragments);
+
+    return ret;
+}
+
+int isa_l_reconstruct(void *desc, char **data, char **parity,
+        int *missing_idxs, int destination_idx, int blocksize)
+{
+    isa_l_descriptor *isa_l_desc = (isa_l_descriptor*) desc;
+    unsigned char *g_tbls = NULL;
+    unsigned char *decode_matrix = NULL;
+    unsigned char *decode_inverse = NULL;
+    unsigned char *inverse_rows = NULL;
+    unsigned char *reconstruct_buf = NULL;
+    unsigned char **available_fragments = NULL;
+    int k = isa_l_desc->k;
+    int m = isa_l_desc->m;
+    int n = k + m;
+    int ret = -1;
+    int i, j;
+    uint64_t missing_bm = convert_list_to_bitmap(missing_idxs);
+    int inverse_row = -1;
+
+    /**
+     * Get available elements and compute the inverse of their
+     * corresponding rows.
+     */
+    decode_matrix = isa_l_get_decode_matrix(k, m, isa_l_desc->matrix, missing_idxs);
+
+    if (NULL == decode_matrix) {
+        goto out;
+    }
+
+    decode_inverse = (unsigned char*)malloc(sizeof(unsigned char) * k * k);
+
+    if (NULL == decode_inverse) {
+        goto out;
+    }
+
+    int im_ret = isa_l_desc->gf_invert_matrix(decode_matrix, decode_inverse, k);
+    if (im_ret < 0) {
+        goto out;
+    }
+
+    /**
+     * Get the row needed to reconstruct
+     */
+    inverse_rows = get_inverse_rows(k, m, decode_inverse, isa_l_desc->matrix, missing_idxs, isa_l_desc->gf_mul);
+
+    // Generate g_tbls from computed decode matrix (k x k) matrix
+    g_tbls = malloc(sizeof(unsigned char) * (k * m * 32));
+    if (NULL == g_tbls) {
+        goto out;
+    }
+
+    /**
+     * Fill in the available elements
+     */
+    available_fragments = (unsigned char**)malloc(sizeof(unsigned char*)*k);
+    if (NULL == available_fragments) {
+        goto out;
+    }
+
+    j = 0;
+    for (i = 0; i < n; i++) {
+        if (missing_bm & (1 << i)) {
+            continue;
+        }
+        if (j == k) {
+          break;
+        }
+        if (i < k) {
+            available_fragments[j] = (unsigned char*)data[i];
+        } else {
+            available_fragments[j] = (unsigned char*)parity[i-k];
+        }
+        j++;
+    }
+
+    /**
+     * Copy pointer of buffer to reconstruct
+     */
+    j = 0;
+    for (i = 0; i < n; i++) {
+        if (missing_bm & (1 << i)) {
+            if (i == destination_idx) {
+                if (i < k) {
+                    reconstruct_buf = (unsigned char*)data[i];
+                } else {
+                    reconstruct_buf = (unsigned char*)parity[i-k];
+                }
+                inverse_row = j;
+                break;
+            }
+            j++;
+        }
+    }
+
+    /**
+     * Do the reconstruction
+     */
+    isa_l_desc->ec_init_tables(k, 1, &inverse_rows[inverse_row * k], g_tbls);
+
+    isa_l_desc->ec_encode_data(blocksize, k, 1, g_tbls, (unsigned char**)available_fragments,
+                               (unsigned char**)&reconstruct_buf);
+
+    ret = 0;
+out:
+    free(g_tbls);
+    free(decode_matrix);
+    free(decode_inverse);
+    free(inverse_rows);
+    free(available_fragments);
+
+    return ret;
+}
+
+int isa_l_min_fragments(void *desc, int *missing_idxs,
+        int *fragments_to_exclude, int *fragments_needed)
+{
+    isa_l_descriptor *isa_l_desc = (isa_l_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 < (isa_l_desc->k + isa_l_desc->m); i++) {
+        if (!(missing_bm & (1 << i))) {
+            fragments_needed[j] = i;
+            j++;
+        }
+        if (j == isa_l_desc->k) {
+            ret = 0;
+            fragments_needed[j] = -1;
+            break;
+        }
+    }
+
+    return ret;
+}
+
+/**
+ * Return the element-size, which is the number of bits stored
+ * on a given device, per codeword.  This is always 8 in ISA-L
+ *
+ * Returns the size in bits!
+ */
+int isa_l_element_size(void* desc)
+{
+  return 8;
+}
+
+int isa_l_exit(void *desc)
+{
+    isa_l_descriptor *isa_l_desc = NULL;
+
+    isa_l_desc = (isa_l_descriptor*) desc;
+
+    free(isa_l_desc);
+
+    return 0;
+}
+
+
+void * isa_l_common_init(struct ec_backend_args *args, void *backend_sohandle,
+        const char* gen_matrix_func_name)
+{
+    isa_l_descriptor *desc = NULL;
+
+    desc = (isa_l_descriptor *)malloc(sizeof(isa_l_descriptor));
+    if (NULL == desc) {
+        return NULL;
+    }
+
+    desc->k = args->uargs.k;
+    desc->m = args->uargs.m;
+    if (args->uargs.w <= 0)
+        args->uargs.w = ISA_L_W;
+    desc->w = args->uargs.w;
+
+    /* validate EC arguments */
+    {
+        long long max_symbols = 1LL << desc->w;
+        if ((desc->k + desc->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 {
+        ec_encode_data_func encodep;
+        ec_init_tables_func init_tablesp;
+        gf_gen_encoding_matrix_func gen_matrixp;
+        gf_invert_matrix_func invert_matrixp;
+        gf_mul_func gf_mulp;
+        void *vptr;
+    } func_handle = {.vptr = NULL};
+
+    /* fill in function addresses */
+    func_handle.vptr = NULL;
+    func_handle.vptr = dlsym(backend_sohandle, "ec_encode_data");
+    desc->ec_encode_data = func_handle.encodep;
+    if (NULL == desc->ec_encode_data) {
+        goto error;
+    }
+
+    func_handle.vptr = NULL;
+    func_handle.vptr = dlsym(backend_sohandle, "ec_init_tables");
+    desc->ec_init_tables = func_handle.init_tablesp;
+    if (NULL == desc->ec_init_tables) {
+        goto error;
+    }
+
+    func_handle.vptr = NULL;
+    func_handle.vptr = dlsym(backend_sohandle, gen_matrix_func_name);
+    desc->gf_gen_encoding_matrix = func_handle.gen_matrixp;
+    if (NULL == desc->gf_gen_encoding_matrix) {
+        goto error;
+    }
+
+    func_handle.vptr = NULL;
+    func_handle.vptr = dlsym(backend_sohandle, "gf_invert_matrix");
+    desc->gf_invert_matrix = func_handle.invert_matrixp;
+    if (NULL == desc->gf_invert_matrix) {
+        goto error;
+    }
+
+    func_handle.vptr = NULL;
+    func_handle.vptr = dlsym(backend_sohandle, "gf_mul");
+    desc->gf_mul = func_handle.gf_mulp;
+    if (NULL == desc->gf_mul) {
+        goto error;
+    }
+
+    desc->matrix = malloc(sizeof(char) * desc->k * (desc->k + desc->m));
+    if (NULL == desc->matrix) {
+        goto error;
+    }
+
+    /**
+     * Generate ISA-L encoding matrix
+     * Note that this is an abstract func from each backend
+     */
+    desc->gf_gen_encoding_matrix(desc->matrix, desc->k + desc->m, desc->k);
+
+    return desc;
+
+error:
+    free(desc);
+
+    return NULL;
+}
diff --git a/src/backends/isa-l/isa_l_rs_cauchy.c b/src/backends/isa-l/isa_l_rs_cauchy.c
new file mode 100644
index 0000000..11bac53
--- /dev/null
+++ b/src/backends/isa-l/isa_l_rs_cauchy.c
@@ -0,0 +1,86 @@
+/*
+ * Copyright 2014 Kevin M Greenan
+ * Copyright 2014 Tushar Gohad
+ * Copyright 2016 Kota Tsuyuzaki
+ *
+ * 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.
+ *
+ * isa_l_rs_cauchy backend implementation
+ *
+ * vi: set noai tw=79 ts=4 sw=4:
+ */
+
+#include <stdlib.h>
+#include "erasurecode_backend.h"
+#include "isa_l_common.h"
+
+#define ISA_L_RS_CAUCHY_LIB_MAJOR 2
+#define ISA_L_RS_CAUCHY_LIB_MINOR 14
+#define ISA_L_RS_CAUCHY_LIB_REV   1
+#define ISA_L_RS_CAUCHY_LIB_VER_STR "2.14"
+#define ISA_L_RS_CAUCHY_LIB_NAME "isa_l_rs_cauchy"
+#if defined(__MACOS__) || defined(__MACOSX__) || defined(__OSX__) || defined(__APPLE__)
+#define ISA_L_RS_CAUCHY_SO_NAME "libisal.dylib"
+#else
+#define ISA_L_RS_CAUCHY_SO_NAME "libisal.so.2"
+#endif
+
+/* Forward declarations */
+struct ec_backend_op_stubs isa_l_rs_cauchy_ops;
+struct ec_backend isa_l_rs_cauchy;
+struct ec_backend_common backend_isa_l_rs_cauchy;
+
+static void * isa_l_rs_cauchy_init(struct ec_backend_args *args,
+        void *backend_sohandle)
+{
+    return isa_l_common_init(args, backend_sohandle, "gf_gen_cauchy1_matrix");
+}
+
+/*
+ * For the time being, we only claim compatibility with versions that
+ * match exactly
+ */
+static bool isa_l_rs_cauchy_is_compatible_with(uint32_t version) {
+    return version == backend_isa_l_rs_cauchy.ec_backend_version;
+}
+
+struct ec_backend_op_stubs isa_l_rs_cauchy_op_stubs = {
+    .INIT                       = isa_l_rs_cauchy_init,
+    .EXIT                       = isa_l_exit,
+    .ENCODE                     = isa_l_encode,
+    .DECODE                     = isa_l_decode,
+    .FRAGSNEEDED                = isa_l_min_fragments,
+    .RECONSTRUCT                = isa_l_reconstruct,
+    .ELEMENTSIZE                = isa_l_element_size,
+    .ISCOMPATIBLEWITH           = isa_l_rs_cauchy_is_compatible_with,
+};
+
+struct ec_backend_common backend_isa_l_rs_cauchy = {
+    .id                         = EC_BACKEND_ISA_L_RS_CAUCHY,
+    .name                       = ISA_L_RS_CAUCHY_LIB_NAME,
+    .soname                     = ISA_L_RS_CAUCHY_SO_NAME,
+    .soversion                  = ISA_L_RS_CAUCHY_LIB_VER_STR,
+    .ops                        = &isa_l_rs_cauchy_op_stubs,
+    .backend_metadata_size      = 0,
+    .ec_backend_version         = _VERSION(ISA_L_RS_CAUCHY_LIB_MAJOR,
+                                           ISA_L_RS_CAUCHY_LIB_MINOR,
+                                           ISA_L_RS_CAUCHY_LIB_REV),
+};
diff --git a/src/backends/isa-l/isa_l_rs_vand.c b/src/backends/isa-l/isa_l_rs_vand.c
index ebce441..a084beb 100644
--- a/src/backends/isa-l/isa_l_rs_vand.c
+++ b/src/backends/isa-l/isa_l_rs_vand.c
@@ -27,13 +27,9 @@
  * 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"
+#include "isa_l_common.h"
 
 #define ISA_L_RS_VAND_LIB_MAJOR 2
 #define ISA_L_RS_VAND_LIB_MINOR 13
@@ -51,543 +47,10 @@ struct ec_backend_op_stubs isa_l_rs_vand_ops;
 struct ec_backend isa_l_rs_vand;
 struct ec_backend_common backend_isa_l_rs_vand;
 
-typedef void (*ec_encode_data_func)(int, int, int, unsigned char*, unsigned char **, unsigned char **);
-typedef void (*ec_init_tables_func)(int, int, unsigned char*, unsigned char *);
-typedef void (*gf_gen_rs_matrix_func)(unsigned char*, int, int);
-typedef int (*gf_invert_matrix_func)(unsigned char*, unsigned char*, const int);
-typedef unsigned char (*gf_mul_func)(unsigned char, unsigned char);
-
-struct isa_l_rs_vand_descriptor {
-    /* calls required for init */
-    ec_init_tables_func ec_init_tables;
-    gf_gen_rs_matrix_func gf_gen_rs_matrix;
-
-    /* calls required for encode */
-    ec_encode_data_func ec_encode_data;
-
-    /* calls required for decode and reconstruct */
-    gf_invert_matrix_func gf_invert_matrix;
-
-    /* multiplication function used by ISA-L */
-    gf_mul_func gf_mul;
-
-    /* fields needed to hold state */
-    unsigned char *matrix;
-    int k;
-    int m;
-    int w;
-};
-
-static int isa_l_rs_vand_encode(void *desc, char **data, char **parity,
-        int blocksize)
-{
-    struct isa_l_rs_vand_descriptor *isa_l_desc =
-        (struct isa_l_rs_vand_descriptor*) desc;
-
-    unsigned char *g_tbls = NULL;
-    int k = isa_l_desc->k;
-    int m = isa_l_desc->m;
-
-    // Generate g_tbls from encode matrix encode_matrix
-    g_tbls = malloc(sizeof(unsigned char) * (k * m * 32));
-    if (NULL == g_tbls) {
-        return -1;
-    }
-
-    isa_l_desc->ec_init_tables(k, m, &isa_l_desc->matrix[k * k], g_tbls);
-
-    /* FIXME - make ec_encode_data return a value */
-    isa_l_desc->ec_encode_data(blocksize, k, m, g_tbls, (unsigned char**)data,
-                               (unsigned char**)parity);
-    free(g_tbls);
-    return 0;
-}
-
-static unsigned char* isa_l_get_decode_matrix(int k, int m, unsigned char *encode_matrix, int *missing_idxs)
-{
-    int i = 0, j = 0, l = 0;
-    int n = k + m;
-    unsigned char *decode_matrix = malloc(sizeof(unsigned char) * k * k);
-    uint64_t missing_bm = convert_list_to_bitmap(missing_idxs);
-
-    while (i < k && l < n) {
-        if (((1 << l) & missing_bm) == 0) {
-            for (j = 0; j < k; j++) {
-                decode_matrix[(k * i) + j] = encode_matrix[(k * l) + j];
-            }
-            i++;
-        }
-        l++;
-    }
-
-    if (i != k) {
-        free(decode_matrix);
-        decode_matrix = NULL;
-    }
-
-    return decode_matrix;
-}
-
-static int get_num_missing_elements(int *missing_idxs)
-{
-    int i = 0;
-
-    while (missing_idxs[i] > -1) {
-        i++;
-    }
-
-    return i;
-}
-
-static void mult_and_xor_row(unsigned char *to_row,
-                             unsigned char *from_row,
-                             unsigned char val,
-                             int num_elems,
-                             gf_mul_func gf_mul)
-{
-    int i;
-
-    for (i = 0; i < num_elems; i++) {
-        to_row[i] ^= gf_mul(val, from_row[i]);
-    }
-}
-
-/*
- * TODO: Add in missing parity rows and adjust the inverse_rows to
- * be used for parity.
- */
-static unsigned char* get_inverse_rows(int k,
-                                       int m,
-                                       unsigned char *decode_inverse,
-                                       unsigned char* encode_matrix,
-                                       int *missing_idxs,
-                                       gf_mul_func gf_mul)
-{
-    uint64_t missing_bm = convert_list_to_bitmap(missing_idxs);
-    int num_missing_elements = get_num_missing_elements(missing_idxs);
-    unsigned char *inverse_rows = (unsigned char*)malloc(sizeof(unsigned
-                                    char*) * k * num_missing_elements);
-    int i, j, l = 0;
-    int n = k + m;
-
-    if (NULL == inverse_rows) {
-        return NULL;
-    }
-
-    memset(inverse_rows, 0, sizeof(unsigned
-                                    char*) * k * num_missing_elements);
-
-    /*
-     * Fill in rows for missing data
-     */
-    for (i = 0; i < k; i++) {
-        if ((1 << i) & missing_bm) {
-            for (j = 0; j < k; j++) {
-                inverse_rows[(l * k) + j] = decode_inverse[(i * k) + j];
-            }
-            l++;
-        }
-    }
-
-    /*
-     * Process missing parity.
-     *
-     * Start with an all-zero row.
-     *
-     * For each data element, if the data element is:
-     *
-     * Available: XOR the corresponding coefficient from the
-     * encoding matrix.
-     *
-     * Unavailable: multiply corresponding coefficient with
-     * the row that corresponds to the missing data in inverse_rows
-     * and XOR the resulting row with this row.
-     */
-    for (i = k; i < n; i++) {
-        // Parity is missing
-        if ((1 << i) & missing_bm) {
-            int d_idx_avail = 0;
-            int d_idx_unavail = 0;
-            for (j = 0; j < k; j++) {
-                // This data is available, so we can use the encode matrix
-                if (((1 << j) & missing_bm) == 0) {
-                    inverse_rows[(l * k) + d_idx_avail] ^= encode_matrix[(i * k) + j];
-                    d_idx_avail++;
-                } else {
-                    mult_and_xor_row(&inverse_rows[l * k],
-                                     &inverse_rows[d_idx_unavail * k],
-                                     encode_matrix[(i * k) + j],
-                                     k,
-                                     gf_mul);
-                    d_idx_unavail++;
-                }
-            }
-            l++;
-        }
-    }
-    return inverse_rows;
-}
-
-static int isa_l_rs_vand_decode(void *desc, char **data, char **parity,
-        int *missing_idxs, int blocksize)
-{
-    struct isa_l_rs_vand_descriptor *isa_l_desc =
-        (struct isa_l_rs_vand_descriptor*)desc;
-
-    unsigned char *g_tbls = NULL;
-    unsigned char *decode_matrix = NULL;
-    unsigned char *decode_inverse = NULL;
-    unsigned char *inverse_rows = NULL;
-    unsigned char **decoded_elements = NULL;
-    unsigned char **available_fragments = NULL;
-    int k = isa_l_desc->k;
-    int m = isa_l_desc->m;
-    int n = k + m;
-    int ret = -1;
-    int i, j;
-
-    int num_missing_elements = get_num_missing_elements(missing_idxs);
-    uint64_t missing_bm = convert_list_to_bitmap(missing_idxs);
-
-    decode_matrix = isa_l_get_decode_matrix(k, m, isa_l_desc->matrix, missing_idxs);
-
-    if (NULL == decode_matrix) {
-        goto out;
-    }
-
-    decode_inverse = (unsigned char*)malloc(sizeof(unsigned char) * k * k);
-
-    if (NULL == decode_inverse) {
-        goto out;
-    }
-
-    int im_ret = isa_l_desc->gf_invert_matrix(decode_matrix, decode_inverse, k);
-    if (im_ret < 0) {
-        goto out;
-    }
-
-    // Generate g_tbls from computed decode matrix (k x k) matrix
-    g_tbls = malloc(sizeof(unsigned char) * (k * m * 32));
-    if (NULL == g_tbls) {
-        goto out;
-    }
-
-    inverse_rows = get_inverse_rows(k, m, decode_inverse, isa_l_desc->matrix, missing_idxs, isa_l_desc->gf_mul);
-
-    decoded_elements = (unsigned char**)malloc(sizeof(unsigned char*)*num_missing_elements);
-    if (NULL == decoded_elements) {
-        goto out;
-    }
-
-    available_fragments = (unsigned char**)malloc(sizeof(unsigned char*)*k);
-    if (NULL == available_fragments) {
-        goto out;
-    }
-
-    j = 0;
-    for (i = 0; i < n; i++) {
-        if (missing_bm & (1 << i)) {
-            continue;
-        }
-        if (j == k) {
-            break;
-        }
-        if (i < k) {
-            available_fragments[j] = (unsigned char*)data[i];
-        } else {
-            available_fragments[j] = (unsigned char*)parity[i-k];
-        }
-        j++;
-    }
-
-    // Grab pointers to memory needed for missing data fragments
-    j = 0;
-    for (i = 0; i < k; i++) {
-        if (missing_bm & (1 << i)) {
-            decoded_elements[j] = (unsigned char*)data[i];
-            j++;
-        }
-    }
-    for (i = k; i < n; i++) {
-        if (missing_bm & (1 << i)) {
-            decoded_elements[j] = (unsigned char*)parity[i - k];
-            j++;
-        }
-    }
-
-    isa_l_desc->ec_init_tables(k, num_missing_elements, inverse_rows, g_tbls);
-
-    isa_l_desc->ec_encode_data(blocksize, k, num_missing_elements, g_tbls, (unsigned char**)available_fragments,
-                               (unsigned char**)decoded_elements);
-
-    ret = 0;
-
-out:
-    free(g_tbls);
-    free(decode_matrix);
-    free(decode_inverse);
-    free(inverse_rows);
-    free(decoded_elements);
-    free(available_fragments);
-
-    return ret;
-}
-
-static int isa_l_rs_vand_reconstruct(void *desc, char **data, char **parity,
-        int *missing_idxs, int destination_idx, int blocksize)
-{
-    struct isa_l_rs_vand_descriptor *isa_l_desc =
-        (struct isa_l_rs_vand_descriptor*) desc;
-    unsigned char *g_tbls = NULL;
-    unsigned char *decode_matrix = NULL;
-    unsigned char *decode_inverse = NULL;
-    unsigned char *inverse_rows = NULL;
-    unsigned char *reconstruct_buf = NULL;
-    unsigned char **available_fragments = NULL;
-    int k = isa_l_desc->k;
-    int m = isa_l_desc->m;
-    int n = k + m;
-    int ret = -1;
-    int i, j;
-    uint64_t missing_bm = convert_list_to_bitmap(missing_idxs);
-    int inverse_row = -1;
-
-    /**
-     * Get available elements and compute the inverse of their
-     * corresponding rows.
-     */
-    decode_matrix = isa_l_get_decode_matrix(k, m, isa_l_desc->matrix, missing_idxs);
-
-    if (NULL == decode_matrix) {
-        goto out;
-    }
-
-    decode_inverse = (unsigned char*)malloc(sizeof(unsigned char) * k * k);
-
-    if (NULL == decode_inverse) {
-        goto out;
-    }
-
-    int im_ret = isa_l_desc->gf_invert_matrix(decode_matrix, decode_inverse, k);
-    if (im_ret < 0) {
-        goto out;
-    }
-
-    /**
-     * Get the row needed to reconstruct
-     */
-    inverse_rows = get_inverse_rows(k, m, decode_inverse, isa_l_desc->matrix, missing_idxs, isa_l_desc->gf_mul);
-
-    // Generate g_tbls from computed decode matrix (k x k) matrix
-    g_tbls = malloc(sizeof(unsigned char) * (k * m * 32));
-    if (NULL == g_tbls) {
-        goto out;
-    }
-
-    /**
-     * Fill in the available elements
-     */
-    available_fragments = (unsigned char**)malloc(sizeof(unsigned char*)*k);
-    if (NULL == available_fragments) {
-        goto out;
-    }
-
-    j = 0;
-    for (i = 0; i < n; i++) {
-        if (missing_bm & (1 << i)) {
-            continue;
-        }
-        if (j == k) {
-          break;
-        }
-        if (i < k) {
-            available_fragments[j] = (unsigned char*)data[i];
-        } else {
-            available_fragments[j] = (unsigned char*)parity[i-k];
-        }
-        j++;
-    }
-
-    /**
-     * Copy pointer of buffer to reconstruct
-     */
-    j = 0;
-    for (i = 0; i < n; i++) {
-        if (missing_bm & (1 << i)) {
-            if (i == destination_idx) {
-                if (i < k) {
-                    reconstruct_buf = (unsigned char*)data[i];
-                } else {
-                    reconstruct_buf = (unsigned char*)parity[i-k];
-                }
-                inverse_row = j;
-                break;
-            }
-            j++;
-        }
-    }
-
-    /**
-     * Do the reconstruction
-     */
-    isa_l_desc->ec_init_tables(k, 1, &inverse_rows[inverse_row * k], g_tbls);
-
-    isa_l_desc->ec_encode_data(blocksize, k, 1, g_tbls, (unsigned char**)available_fragments,
-                               (unsigned char**)&reconstruct_buf);
-
-    ret = 0;
-out:
-    free(g_tbls);
-    free(decode_matrix);
-    free(decode_inverse);
-    free(inverse_rows);
-    free(available_fragments);
-
-    return ret;
-}
-
-static int isa_l_rs_vand_min_fragments(void *desc, int *missing_idxs,
-        int *fragments_to_exclude, int *fragments_needed)
-{
-    struct isa_l_rs_vand_descriptor *isa_l_desc =
-        (struct isa_l_rs_vand_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 < (isa_l_desc->k + isa_l_desc->m); i++) {
-        if (!(missing_bm & (1 << i))) {
-            fragments_needed[j] = i;
-            j++;
-        }
-        if (j == isa_l_desc->k) {
-            ret = 0;
-            fragments_needed[j] = -1;
-            break;
-        }
-    }
-
-    return ret;
-}
-
-#define ISA_L_W 8
 static void * isa_l_rs_vand_init(struct ec_backend_args *args,
         void *backend_sohandle)
 {
-    struct isa_l_rs_vand_descriptor *desc = NULL;
-
-    desc = (struct isa_l_rs_vand_descriptor *)
-           malloc(sizeof(struct isa_l_rs_vand_descriptor));
-    if (NULL == desc) {
-        return NULL;
-    }
-
-    desc->k = args->uargs.k;
-    desc->m = args->uargs.m;
-    if (args->uargs.w <= 0)
-        args->uargs.w = ISA_L_W;
-    desc->w = args->uargs.w;
-
-    /* validate EC arguments */
-    {
-        long long max_symbols = 1LL << desc->w;
-        if ((desc->k + desc->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 {
-        ec_encode_data_func encodep;
-        ec_init_tables_func init_tablesp;
-        gf_gen_rs_matrix_func gen_matrixp;
-        gf_invert_matrix_func invert_matrixp;
-        gf_mul_func gf_mulp;
-        void *vptr;
-    } func_handle = {.vptr = NULL};
-
-    /* fill in function addresses */
-    func_handle.vptr = NULL;
-    func_handle.vptr = dlsym(backend_sohandle, "ec_encode_data");
-    desc->ec_encode_data = func_handle.encodep;
-    if (NULL == desc->ec_encode_data) {
-        goto error;
-    }
-
-    func_handle.vptr = NULL;
-    func_handle.vptr = dlsym(backend_sohandle, "ec_init_tables");
-    desc->ec_init_tables = func_handle.init_tablesp;
-    if (NULL == desc->ec_init_tables) {
-        goto error;
-    }
-
-    func_handle.vptr = NULL;
-    func_handle.vptr = dlsym(backend_sohandle, "gf_gen_rs_matrix");
-    desc->gf_gen_rs_matrix = func_handle.gen_matrixp;
-    if (NULL == desc->gf_gen_rs_matrix) {
-        goto error;
-    }
-
-    func_handle.vptr = NULL;
-    func_handle.vptr = dlsym(backend_sohandle, "gf_invert_matrix");
-    desc->gf_invert_matrix = func_handle.invert_matrixp;
-    if (NULL == desc->gf_invert_matrix) {
-        goto error;
-    }
-
-    func_handle.vptr = NULL;
-    func_handle.vptr = dlsym(backend_sohandle, "gf_mul");
-    desc->gf_mul = func_handle.gf_mulp;
-    if (NULL == desc->gf_mul) {
-        goto error;
-    }
-
-    desc->matrix = malloc(sizeof(char) * desc->k * (desc->k + desc->m));
-    if (NULL == desc->matrix) {
-        goto error;
-    }
-
-    /**
-     * Generate ISA-L encoding matrix
-     */
-    desc->gf_gen_rs_matrix(desc->matrix, desc->k + desc->m, desc->k);
-
-    return desc;
-
-error:
-    free(desc);
-
-    return NULL;
-}
-
-/**
- * Return the element-size, which is the number of bits stored
- * on a given device, per codeword.  This is always 8 in ISA-L
- *
- * Returns the size in bits!
- */
-static int
-isa_l_rs_vand_element_size(void* desc)
-{
-  return 8;
-}
-
-static int isa_l_rs_vand_exit(void *desc)
-{
-    struct isa_l_rs_vand_descriptor *isa_l_desc = NULL;
-
-    isa_l_desc = (struct isa_l_rs_vand_descriptor*) desc;
-
-    free(isa_l_desc);
-
-    return 0;
+    return isa_l_common_init(args, backend_sohandle, "gf_gen_rs_matrix");
 }
 
 /*
@@ -600,12 +63,12 @@ static bool isa_l_rs_vand_is_compatible_with(uint32_t version) {
 
 struct ec_backend_op_stubs isa_l_rs_vand_op_stubs = {
     .INIT                       = isa_l_rs_vand_init,
-    .EXIT                       = isa_l_rs_vand_exit,
-    .ENCODE                     = isa_l_rs_vand_encode,
-    .DECODE                     = isa_l_rs_vand_decode,
-    .FRAGSNEEDED                = isa_l_rs_vand_min_fragments,
-    .RECONSTRUCT                = isa_l_rs_vand_reconstruct,
-    .ELEMENTSIZE                = isa_l_rs_vand_element_size,
+    .EXIT                       = isa_l_exit,
+    .ENCODE                     = isa_l_encode,
+    .DECODE                     = isa_l_decode,
+    .FRAGSNEEDED                = isa_l_min_fragments,
+    .RECONSTRUCT                = isa_l_reconstruct,
+    .ELEMENTSIZE                = isa_l_element_size,
     .ISCOMPATIBLEWITH           = isa_l_rs_vand_is_compatible_with,
 };
 
diff --git a/src/erasurecode.c b/src/erasurecode.c
index fdae72a..6bc1c2e 100644
--- a/src/erasurecode.c
+++ b/src/erasurecode.c
@@ -49,6 +49,7 @@ extern struct ec_backend_common backend_jerasure_rs_cauchy;
 extern struct ec_backend_common backend_isa_l_rs_vand;
 extern struct ec_backend_common backend_shss;
 extern struct ec_backend_common backend_liberasurecode_rs_vand;
+extern struct ec_backend_common backend_isa_l_rs_cauchy;
 
 ec_backend_t ec_backends_supported[] = {
     (ec_backend_t) &backend_null,
@@ -58,6 +59,7 @@ ec_backend_t ec_backends_supported[] = {
     (ec_backend_t) &backend_isa_l_rs_vand,
     (ec_backend_t) &backend_shss,
     (ec_backend_t) &backend_liberasurecode_rs_vand,
+    (ec_backend_t) &backend_isa_l_rs_cauchy,
     NULL,
 };