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Merge branch 'core-rslib-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull Reed-Solomon library updates from Thomas Gleixner: "A cleanup and fixes series from Ferdinand Blomqvist who analyzed the original Reed-Solomon library from Phil Karn on which the kernel implementation is based on. This comes with a test module which verifies all the various corner cases for correctness" * 'core-rslib-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: rslib: Make some functions static rslib: Fix remaining decoder flaws rslib: Update documentation rslib: Fix handling of of caller provided syndrome rslib: decode_rs: Code cleanup rslib: decode_rs: Fix length parameter check rslib: Fix decoding of shortened codes rslib: Add tests for the encoder and decoder
This commit is contained in:
Linus Torvalds
commit
568521d058
@ -1754,6 +1754,18 @@ config RBTREE_TEST
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A benchmark measuring the performance of the rbtree library.
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Also includes rbtree invariant checks.
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config REED_SOLOMON_TEST
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tristate "Reed-Solomon library test"
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depends on DEBUG_KERNEL || m
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select REED_SOLOMON
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select REED_SOLOMON_ENC16
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select REED_SOLOMON_DEC16
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help
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This option enables the self-test function of rslib at boot,
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or at module load time.
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If unsure, say N.
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config INTERVAL_TREE_TEST
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tristate "Interval tree test"
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depends on DEBUG_KERNEL
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@ -4,4 +4,4 @@
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#
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obj-$(CONFIG_REED_SOLOMON) += reed_solomon.o
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obj-$(CONFIG_REED_SOLOMON_TEST) += test_rslib.o
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@ -22,6 +22,7 @@
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uint16_t *index_of = rs->index_of;
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uint16_t u, q, tmp, num1, num2, den, discr_r, syn_error;
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int count = 0;
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int num_corrected;
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uint16_t msk = (uint16_t) rs->nn;
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/*
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@ -39,11 +40,21 @@
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/* Check length parameter for validity */
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pad = nn - nroots - len;
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BUG_ON(pad < 0 || pad >= nn);
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BUG_ON(pad < 0 || pad >= nn - nroots);
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/* Does the caller provide the syndrome ? */
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if (s != NULL)
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goto decode;
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if (s != NULL) {
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for (i = 0; i < nroots; i++) {
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/* The syndrome is in index form,
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* so nn represents zero
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*/
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if (s[i] != nn)
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goto decode;
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}
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/* syndrome is zero, no errors to correct */
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return 0;
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}
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/* form the syndromes; i.e., evaluate data(x) at roots of
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* g(x) */
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@ -88,8 +99,7 @@
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/* if syndrome is zero, data[] is a codeword and there are no
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* errors to correct. So return data[] unmodified
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*/
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count = 0;
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goto finish;
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return 0;
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}
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decode:
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@ -99,9 +109,9 @@
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if (no_eras > 0) {
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/* Init lambda to be the erasure locator polynomial */
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lambda[1] = alpha_to[rs_modnn(rs,
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prim * (nn - 1 - eras_pos[0]))];
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prim * (nn - 1 - (eras_pos[0] + pad)))];
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for (i = 1; i < no_eras; i++) {
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u = rs_modnn(rs, prim * (nn - 1 - eras_pos[i]));
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u = rs_modnn(rs, prim * (nn - 1 - (eras_pos[i] + pad)));
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for (j = i + 1; j > 0; j--) {
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tmp = index_of[lambda[j - 1]];
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if (tmp != nn) {
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@ -175,6 +185,15 @@
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if (lambda[i] != nn)
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deg_lambda = i;
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}
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if (deg_lambda == 0) {
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/*
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* deg(lambda) is zero even though the syndrome is non-zero
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* => uncorrectable error detected
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*/
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return -EBADMSG;
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}
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/* Find roots of error+erasure locator polynomial by Chien search */
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memcpy(®[1], &lambda[1], nroots * sizeof(reg[0]));
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count = 0; /* Number of roots of lambda(x) */
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@ -188,6 +207,12 @@
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}
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if (q != 0)
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continue; /* Not a root */
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if (k < pad) {
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/* Impossible error location. Uncorrectable error. */
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return -EBADMSG;
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}
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/* store root (index-form) and error location number */
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root[count] = i;
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loc[count] = k;
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@ -202,8 +227,7 @@
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* deg(lambda) unequal to number of roots => uncorrectable
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* error detected
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*/
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count = -EBADMSG;
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goto finish;
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return -EBADMSG;
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}
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/*
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* Compute err+eras evaluator poly omega(x) = s(x)*lambda(x) (modulo
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@ -223,7 +247,9 @@
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/*
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* Compute error values in poly-form. num1 = omega(inv(X(l))), num2 =
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* inv(X(l))**(fcr-1) and den = lambda_pr(inv(X(l))) all in poly-form
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* Note: we reuse the buffer for b to store the correction pattern
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*/
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num_corrected = 0;
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for (j = count - 1; j >= 0; j--) {
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num1 = 0;
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for (i = deg_omega; i >= 0; i--) {
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@ -231,6 +257,13 @@
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num1 ^= alpha_to[rs_modnn(rs, omega[i] +
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i * root[j])];
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}
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if (num1 == 0) {
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/* Nothing to correct at this position */
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b[j] = 0;
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continue;
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}
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num2 = alpha_to[rs_modnn(rs, root[j] * (fcr - 1) + nn)];
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den = 0;
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@ -242,30 +275,52 @@
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i * root[j])];
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}
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}
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/* Apply error to data */
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if (num1 != 0 && loc[j] >= pad) {
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uint16_t cor = alpha_to[rs_modnn(rs,index_of[num1] +
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index_of[num2] +
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nn - index_of[den])];
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/* Store the error correction pattern, if a
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* correction buffer is available */
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if (corr) {
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corr[j] = cor;
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} else {
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/* If a data buffer is given and the
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* error is inside the message,
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* correct it */
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if (data && (loc[j] < (nn - nroots)))
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data[loc[j] - pad] ^= cor;
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b[j] = alpha_to[rs_modnn(rs, index_of[num1] +
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index_of[num2] +
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nn - index_of[den])];
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num_corrected++;
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}
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/*
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* We compute the syndrome of the 'error' and check that it matches
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* the syndrome of the received word
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*/
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for (i = 0; i < nroots; i++) {
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tmp = 0;
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for (j = 0; j < count; j++) {
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if (b[j] == 0)
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continue;
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k = (fcr + i) * prim * (nn-loc[j]-1);
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tmp ^= alpha_to[rs_modnn(rs, index_of[b[j]] + k)];
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}
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if (tmp != alpha_to[s[i]])
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return -EBADMSG;
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}
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/*
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* Store the error correction pattern, if a
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* correction buffer is available
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*/
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if (corr && eras_pos) {
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j = 0;
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for (i = 0; i < count; i++) {
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if (b[i]) {
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corr[j] = b[i];
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eras_pos[j++] = loc[i] - pad;
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}
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}
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} else if (data && par) {
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/* Apply error to data and parity */
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for (i = 0; i < count; i++) {
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if (loc[i] < (nn - nroots))
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data[loc[i] - pad] ^= b[i];
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else
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par[loc[i] - pad - len] ^= b[i];
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}
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}
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finish:
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if (eras_pos != NULL) {
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for (i = 0; i < count; i++)
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eras_pos[i] = loc[i] - pad;
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}
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return count;
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return num_corrected;
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}
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@ -340,7 +340,8 @@ EXPORT_SYMBOL_GPL(encode_rs8);
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* @data: data field of a given type
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* @par: received parity data field
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* @len: data length
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* @s: syndrome data field (if NULL, syndrome is calculated)
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* @s: syndrome data field, must be in index form
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* (if NULL, syndrome is calculated)
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* @no_eras: number of erasures
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* @eras_pos: position of erasures, can be NULL
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* @invmsk: invert data mask (will be xored on data, not on parity!)
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@ -354,7 +355,8 @@ EXPORT_SYMBOL_GPL(encode_rs8);
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* decoding, so the caller has to ensure that decoder invocations are
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* serialized.
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*
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* Returns the number of corrected bits or -EBADMSG for uncorrectable errors.
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* Returns the number of corrected symbols or -EBADMSG for uncorrectable
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* errors. The count includes errors in the parity.
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*/
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int decode_rs8(struct rs_control *rsc, uint8_t *data, uint16_t *par, int len,
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uint16_t *s, int no_eras, int *eras_pos, uint16_t invmsk,
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@ -391,7 +393,8 @@ EXPORT_SYMBOL_GPL(encode_rs16);
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* @data: data field of a given type
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* @par: received parity data field
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* @len: data length
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* @s: syndrome data field (if NULL, syndrome is calculated)
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* @s: syndrome data field, must be in index form
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* (if NULL, syndrome is calculated)
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* @no_eras: number of erasures
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* @eras_pos: position of erasures, can be NULL
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* @invmsk: invert data mask (will be xored on data, not on parity!)
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@ -403,7 +406,8 @@ EXPORT_SYMBOL_GPL(encode_rs16);
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* decoding, so the caller has to ensure that decoder invocations are
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* serialized.
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*
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* Returns the number of corrected bits or -EBADMSG for uncorrectable errors.
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* Returns the number of corrected symbols or -EBADMSG for uncorrectable
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* errors. The count includes errors in the parity.
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*/
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int decode_rs16(struct rs_control *rsc, uint16_t *data, uint16_t *par, int len,
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uint16_t *s, int no_eras, int *eras_pos, uint16_t invmsk,
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518
lib/reed_solomon/test_rslib.c
Normal file
518
lib/reed_solomon/test_rslib.c
Normal file
@ -0,0 +1,518 @@
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// SPDX-License-Identifier: GPL-2.0
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/*
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* Tests for Generic Reed Solomon encoder / decoder library
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*
|
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* Written by Ferdinand Blomqvist
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* Based on previous work by Phil Karn, KA9Q
|
||||
*/
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#include <linux/rslib.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
|
||||
#include <linux/moduleparam.h>
|
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#include <linux/random.h>
|
||||
#include <linux/slab.h>
|
||||
|
||||
enum verbosity {
|
||||
V_SILENT,
|
||||
V_PROGRESS,
|
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V_CSUMMARY
|
||||
};
|
||||
|
||||
enum method {
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||||
CORR_BUFFER,
|
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CALLER_SYNDROME,
|
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IN_PLACE
|
||||
};
|
||||
|
||||
#define __param(type, name, init, msg) \
|
||||
static type name = init; \
|
||||
module_param(name, type, 0444); \
|
||||
MODULE_PARM_DESC(name, msg)
|
||||
|
||||
__param(int, v, V_PROGRESS, "Verbosity level");
|
||||
__param(int, ewsc, 1, "Erasures without symbol corruption");
|
||||
__param(int, bc, 1, "Test for correct behaviour beyond error correction capacity");
|
||||
|
||||
struct etab {
|
||||
int symsize;
|
||||
int genpoly;
|
||||
int fcs;
|
||||
int prim;
|
||||
int nroots;
|
||||
int ntrials;
|
||||
};
|
||||
|
||||
/* List of codes to test */
|
||||
static struct etab Tab[] = {
|
||||
{2, 0x7, 1, 1, 1, 100000 },
|
||||
{3, 0xb, 1, 1, 2, 100000 },
|
||||
{3, 0xb, 1, 1, 3, 100000 },
|
||||
{3, 0xb, 2, 1, 4, 100000 },
|
||||
{4, 0x13, 1, 1, 4, 10000 },
|
||||
{5, 0x25, 1, 1, 6, 1000 },
|
||||
{6, 0x43, 3, 1, 8, 1000 },
|
||||
{7, 0x89, 1, 1, 14, 500 },
|
||||
{8, 0x11d, 1, 1, 30, 100 },
|
||||
{8, 0x187, 112, 11, 32, 100 },
|
||||
{9, 0x211, 1, 1, 33, 80 },
|
||||
{0, 0, 0, 0, 0, 0},
|
||||
};
|
||||
|
||||
|
||||
struct estat {
|
||||
int dwrong;
|
||||
int irv;
|
||||
int wepos;
|
||||
int nwords;
|
||||
};
|
||||
|
||||
struct bcstat {
|
||||
int rfail;
|
||||
int rsuccess;
|
||||
int noncw;
|
||||
int nwords;
|
||||
};
|
||||
|
||||
struct wspace {
|
||||
uint16_t *c; /* sent codeword */
|
||||
uint16_t *r; /* received word */
|
||||
uint16_t *s; /* syndrome */
|
||||
uint16_t *corr; /* correction buffer */
|
||||
int *errlocs;
|
||||
int *derrlocs;
|
||||
};
|
||||
|
||||
struct pad {
|
||||
int mult;
|
||||
int shift;
|
||||
};
|
||||
|
||||
static struct pad pad_coef[] = {
|
||||
{ 0, 0 },
|
||||
{ 1, 2 },
|
||||
{ 1, 1 },
|
||||
{ 3, 2 },
|
||||
{ 1, 0 },
|
||||
};
|
||||
|
||||
static void free_ws(struct wspace *ws)
|
||||
{
|
||||
if (!ws)
|
||||
return;
|
||||
|
||||
kfree(ws->errlocs);
|
||||
kfree(ws->c);
|
||||
kfree(ws);
|
||||
}
|
||||
|
||||
static struct wspace *alloc_ws(struct rs_codec *rs)
|
||||
{
|
||||
int nroots = rs->nroots;
|
||||
struct wspace *ws;
|
||||
int nn = rs->nn;
|
||||
|
||||
ws = kzalloc(sizeof(*ws), GFP_KERNEL);
|
||||
if (!ws)
|
||||
return NULL;
|
||||
|
||||
ws->c = kmalloc_array(2 * (nn + nroots),
|
||||
sizeof(uint16_t), GFP_KERNEL);
|
||||
if (!ws->c)
|
||||
goto err;
|
||||
|
||||
ws->r = ws->c + nn;
|
||||
ws->s = ws->r + nn;
|
||||
ws->corr = ws->s + nroots;
|
||||
|
||||
ws->errlocs = kmalloc_array(nn + nroots, sizeof(int), GFP_KERNEL);
|
||||
if (!ws->errlocs)
|
||||
goto err;
|
||||
|
||||
ws->derrlocs = ws->errlocs + nn;
|
||||
return ws;
|
||||
|
||||
err:
|
||||
free_ws(ws);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
* Generates a random codeword and stores it in c. Generates random errors and
|
||||
* erasures, and stores the random word with errors in r. Erasure positions are
|
||||
* stored in derrlocs, while errlocs has one of three values in every position:
|
||||
*
|
||||
* 0 if there is no error in this position;
|
||||
* 1 if there is a symbol error in this position;
|
||||
* 2 if there is an erasure without symbol corruption.
|
||||
*
|
||||
* Returns the number of corrupted symbols.
|
||||
*/
|
||||
static int get_rcw_we(struct rs_control *rs, struct wspace *ws,
|
||||
int len, int errs, int eras)
|
||||
{
|
||||
int nroots = rs->codec->nroots;
|
||||
int *derrlocs = ws->derrlocs;
|
||||
int *errlocs = ws->errlocs;
|
||||
int dlen = len - nroots;
|
||||
int nn = rs->codec->nn;
|
||||
uint16_t *c = ws->c;
|
||||
uint16_t *r = ws->r;
|
||||
int errval;
|
||||
int errloc;
|
||||
int i;
|
||||
|
||||
/* Load c with random data and encode */
|
||||
for (i = 0; i < dlen; i++)
|
||||
c[i] = prandom_u32() & nn;
|
||||
|
||||
memset(c + dlen, 0, nroots * sizeof(*c));
|
||||
encode_rs16(rs, c, dlen, c + dlen, 0);
|
||||
|
||||
/* Make copyand add errors and erasures */
|
||||
memcpy(r, c, len * sizeof(*r));
|
||||
memset(errlocs, 0, len * sizeof(*errlocs));
|
||||
memset(derrlocs, 0, nroots * sizeof(*derrlocs));
|
||||
|
||||
/* Generating random errors */
|
||||
for (i = 0; i < errs; i++) {
|
||||
do {
|
||||
/* Error value must be nonzero */
|
||||
errval = prandom_u32() & nn;
|
||||
} while (errval == 0);
|
||||
|
||||
do {
|
||||
/* Must not choose the same location twice */
|
||||
errloc = prandom_u32() % len;
|
||||
} while (errlocs[errloc] != 0);
|
||||
|
||||
errlocs[errloc] = 1;
|
||||
r[errloc] ^= errval;
|
||||
}
|
||||
|
||||
/* Generating random erasures */
|
||||
for (i = 0; i < eras; i++) {
|
||||
do {
|
||||
/* Must not choose the same location twice */
|
||||
errloc = prandom_u32() % len;
|
||||
} while (errlocs[errloc] != 0);
|
||||
|
||||
derrlocs[i] = errloc;
|
||||
|
||||
if (ewsc && (prandom_u32() & 1)) {
|
||||
/* Erasure with the symbol intact */
|
||||
errlocs[errloc] = 2;
|
||||
} else {
|
||||
/* Erasure with corrupted symbol */
|
||||
do {
|
||||
/* Error value must be nonzero */
|
||||
errval = prandom_u32() & nn;
|
||||
} while (errval == 0);
|
||||
|
||||
errlocs[errloc] = 1;
|
||||
r[errloc] ^= errval;
|
||||
errs++;
|
||||
}
|
||||
}
|
||||
|
||||
return errs;
|
||||
}
|
||||
|
||||
static void fix_err(uint16_t *data, int nerrs, uint16_t *corr, int *errlocs)
|
||||
{
|
||||
int i;
|
||||
|
||||
for (i = 0; i < nerrs; i++)
|
||||
data[errlocs[i]] ^= corr[i];
|
||||
}
|
||||
|
||||
static void compute_syndrome(struct rs_control *rsc, uint16_t *data,
|
||||
int len, uint16_t *syn)
|
||||
{
|
||||
struct rs_codec *rs = rsc->codec;
|
||||
uint16_t *alpha_to = rs->alpha_to;
|
||||
uint16_t *index_of = rs->index_of;
|
||||
int nroots = rs->nroots;
|
||||
int prim = rs->prim;
|
||||
int fcr = rs->fcr;
|
||||
int i, j;
|
||||
|
||||
/* Calculating syndrome */
|
||||
for (i = 0; i < nroots; i++) {
|
||||
syn[i] = data[0];
|
||||
for (j = 1; j < len; j++) {
|
||||
if (syn[i] == 0) {
|
||||
syn[i] = data[j];
|
||||
} else {
|
||||
syn[i] = data[j] ^
|
||||
alpha_to[rs_modnn(rs, index_of[syn[i]]
|
||||
+ (fcr + i) * prim)];
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/* Convert to index form */
|
||||
for (i = 0; i < nroots; i++)
|
||||
syn[i] = rs->index_of[syn[i]];
|
||||
}
|
||||
|
||||
/* Test up to error correction capacity */
|
||||
static void test_uc(struct rs_control *rs, int len, int errs,
|
||||
int eras, int trials, struct estat *stat,
|
||||
struct wspace *ws, int method)
|
||||
{
|
||||
int dlen = len - rs->codec->nroots;
|
||||
int *derrlocs = ws->derrlocs;
|
||||
int *errlocs = ws->errlocs;
|
||||
uint16_t *corr = ws->corr;
|
||||
uint16_t *c = ws->c;
|
||||
uint16_t *r = ws->r;
|
||||
uint16_t *s = ws->s;
|
||||
int derrs, nerrs;
|
||||
int i, j;
|
||||
|
||||
for (j = 0; j < trials; j++) {
|
||||
nerrs = get_rcw_we(rs, ws, len, errs, eras);
|
||||
|
||||
switch (method) {
|
||||
case CORR_BUFFER:
|
||||
derrs = decode_rs16(rs, r, r + dlen, dlen,
|
||||
NULL, eras, derrlocs, 0, corr);
|
||||
fix_err(r, derrs, corr, derrlocs);
|
||||
break;
|
||||
case CALLER_SYNDROME:
|
||||
compute_syndrome(rs, r, len, s);
|
||||
derrs = decode_rs16(rs, NULL, NULL, dlen,
|
||||
s, eras, derrlocs, 0, corr);
|
||||
fix_err(r, derrs, corr, derrlocs);
|
||||
break;
|
||||
case IN_PLACE:
|
||||
derrs = decode_rs16(rs, r, r + dlen, dlen,
|
||||
NULL, eras, derrlocs, 0, NULL);
|
||||
break;
|
||||
default:
|
||||
continue;
|
||||
}
|
||||
|
||||
if (derrs != nerrs)
|
||||
stat->irv++;
|
||||
|
||||
if (method != IN_PLACE) {
|
||||
for (i = 0; i < derrs; i++) {
|
||||
if (errlocs[derrlocs[i]] != 1)
|
||||
stat->wepos++;
|
||||
}
|
||||
}
|
||||
|
||||
if (memcmp(r, c, len * sizeof(*r)))
|
||||
stat->dwrong++;
|
||||
}
|
||||
stat->nwords += trials;
|
||||
}
|
||||
|
||||
static int ex_rs_helper(struct rs_control *rs, struct wspace *ws,
|
||||
int len, int trials, int method)
|
||||
{
|
||||
static const char * const desc[] = {
|
||||
"Testing correction buffer interface...",
|
||||
"Testing with caller provided syndrome...",
|
||||
"Testing in-place interface..."
|
||||
};
|
||||
|
||||
struct estat stat = {0, 0, 0, 0};
|
||||
int nroots = rs->codec->nroots;
|
||||
int errs, eras, retval;
|
||||
|
||||
if (v >= V_PROGRESS)
|
||||
pr_info(" %s\n", desc[method]);
|
||||
|
||||
for (errs = 0; errs <= nroots / 2; errs++)
|
||||
for (eras = 0; eras <= nroots - 2 * errs; eras++)
|
||||
test_uc(rs, len, errs, eras, trials, &stat, ws, method);
|
||||
|
||||
if (v >= V_CSUMMARY) {
|
||||
pr_info(" Decodes wrong: %d / %d\n",
|
||||
stat.dwrong, stat.nwords);
|
||||
pr_info(" Wrong return value: %d / %d\n",
|
||||
stat.irv, stat.nwords);
|
||||
if (method != IN_PLACE)
|
||||
pr_info(" Wrong error position: %d\n", stat.wepos);
|
||||
}
|
||||
|
||||
retval = stat.dwrong + stat.wepos + stat.irv;
|
||||
if (retval && v >= V_PROGRESS)
|
||||
pr_warn(" FAIL: %d decoding failures!\n", retval);
|
||||
|
||||
return retval;
|
||||
}
|
||||
|
||||
static int exercise_rs(struct rs_control *rs, struct wspace *ws,
|
||||
int len, int trials)
|
||||
{
|
||||
|
||||
int retval = 0;
|
||||
int i;
|
||||
|
||||
if (v >= V_PROGRESS)
|
||||
pr_info("Testing up to error correction capacity...\n");
|
||||
|
||||
for (i = 0; i <= IN_PLACE; i++)
|
||||
retval |= ex_rs_helper(rs, ws, len, trials, i);
|
||||
|
||||
return retval;
|
||||
}
|
||||
|
||||
/* Tests for correct behaviour beyond error correction capacity */
|
||||
static void test_bc(struct rs_control *rs, int len, int errs,
|
||||
int eras, int trials, struct bcstat *stat,
|
||||
struct wspace *ws)
|
||||
{
|
||||
int nroots = rs->codec->nroots;
|
||||
int dlen = len - nroots;
|
||||
int *derrlocs = ws->derrlocs;
|
||||
uint16_t *corr = ws->corr;
|
||||
uint16_t *r = ws->r;
|
||||
int derrs, j;
|
||||
|
||||
for (j = 0; j < trials; j++) {
|
||||
get_rcw_we(rs, ws, len, errs, eras);
|
||||
derrs = decode_rs16(rs, r, r + dlen, dlen,
|
||||
NULL, eras, derrlocs, 0, corr);
|
||||
fix_err(r, derrs, corr, derrlocs);
|
||||
|
||||
if (derrs >= 0) {
|
||||
stat->rsuccess++;
|
||||
|
||||
/*
|
||||
* We check that the returned word is actually a
|
||||
* codeword. The obious way to do this would be to
|
||||
* compute the syndrome, but we don't want to replicate
|
||||
* that code here. However, all the codes are in
|
||||
* systematic form, and therefore we can encode the
|
||||
* returned word, and see whether the parity changes or
|
||||
* not.
|
||||
*/
|
||||
memset(corr, 0, nroots * sizeof(*corr));
|
||||
encode_rs16(rs, r, dlen, corr, 0);
|
||||
|
||||
if (memcmp(r + dlen, corr, nroots * sizeof(*corr)))
|
||||
stat->noncw++;
|
||||
} else {
|
||||
stat->rfail++;
|
||||
}
|
||||
}
|
||||
stat->nwords += trials;
|
||||
}
|
||||
|
||||
static int exercise_rs_bc(struct rs_control *rs, struct wspace *ws,
|
||||
int len, int trials)
|
||||
{
|
||||
struct bcstat stat = {0, 0, 0, 0};
|
||||
int nroots = rs->codec->nroots;
|
||||
int errs, eras, cutoff;
|
||||
|
||||
if (v >= V_PROGRESS)
|
||||
pr_info("Testing beyond error correction capacity...\n");
|
||||
|
||||
for (errs = 1; errs <= nroots; errs++) {
|
||||
eras = nroots - 2 * errs + 1;
|
||||
if (eras < 0)
|
||||
eras = 0;
|
||||
|
||||
cutoff = nroots <= len - errs ? nroots : len - errs;
|
||||
for (; eras <= cutoff; eras++)
|
||||
test_bc(rs, len, errs, eras, trials, &stat, ws);
|
||||
}
|
||||
|
||||
if (v >= V_CSUMMARY) {
|
||||
pr_info(" decoder gives up: %d / %d\n",
|
||||
stat.rfail, stat.nwords);
|
||||
pr_info(" decoder returns success: %d / %d\n",
|
||||
stat.rsuccess, stat.nwords);
|
||||
pr_info(" not a codeword: %d / %d\n",
|
||||
stat.noncw, stat.rsuccess);
|
||||
}
|
||||
|
||||
if (stat.noncw && v >= V_PROGRESS)
|
||||
pr_warn(" FAIL: %d silent failures!\n", stat.noncw);
|
||||
|
||||
return stat.noncw;
|
||||
}
|
||||
|
||||
static int run_exercise(struct etab *e)
|
||||
{
|
||||
int nn = (1 << e->symsize) - 1;
|
||||
int kk = nn - e->nroots;
|
||||
struct rs_control *rsc;
|
||||
int retval = -ENOMEM;
|
||||
int max_pad = kk - 1;
|
||||
int prev_pad = -1;
|
||||
struct wspace *ws;
|
||||
int i;
|
||||
|
||||
rsc = init_rs(e->symsize, e->genpoly, e->fcs, e->prim, e->nroots);
|
||||
if (!rsc)
|
||||
return retval;
|
||||
|
||||
ws = alloc_ws(rsc->codec);
|
||||
if (!ws)
|
||||
goto err;
|
||||
|
||||
retval = 0;
|
||||
for (i = 0; i < ARRAY_SIZE(pad_coef); i++) {
|
||||
int pad = (pad_coef[i].mult * max_pad) >> pad_coef[i].shift;
|
||||
int len = nn - pad;
|
||||
|
||||
if (pad == prev_pad)
|
||||
continue;
|
||||
|
||||
prev_pad = pad;
|
||||
if (v >= V_PROGRESS) {
|
||||
pr_info("Testing (%d,%d)_%d code...\n",
|
||||
len, kk - pad, nn + 1);
|
||||
}
|
||||
|
||||
retval |= exercise_rs(rsc, ws, len, e->ntrials);
|
||||
if (bc)
|
||||
retval |= exercise_rs_bc(rsc, ws, len, e->ntrials);
|
||||
}
|
||||
|
||||
free_ws(ws);
|
||||
|
||||
err:
|
||||
free_rs(rsc);
|
||||
return retval;
|
||||
}
|
||||
|
||||
static int __init test_rslib_init(void)
|
||||
{
|
||||
int i, fail = 0;
|
||||
|
||||
for (i = 0; Tab[i].symsize != 0 ; i++) {
|
||||
int retval;
|
||||
|
||||
retval = run_exercise(Tab + i);
|
||||
if (retval < 0)
|
||||
return -ENOMEM;
|
||||
|
||||
fail |= retval;
|
||||
}
|
||||
|
||||
if (fail)
|
||||
pr_warn("rslib: test failed\n");
|
||||
else
|
||||
pr_info("rslib: test ok\n");
|
||||
|
||||
return -EAGAIN; /* Fail will directly unload the module */
|
||||
}
|
||||
|
||||
static void __exit test_rslib_exit(void)
|
||||
{
|
||||
}
|
||||
|
||||
module_init(test_rslib_init)
|
||||
module_exit(test_rslib_exit)
|
||||
|
||||
MODULE_LICENSE("GPL");
|
||||
MODULE_AUTHOR("Ferdinand Blomqvist");
|
||||
MODULE_DESCRIPTION("Reed-Solomon library test");
|
||||
Loading…
Reference in New Issue
Block a user