Revision 2fa37fd71396b8eff72d23cafc8c583dd8eb928c authored by kbuild test robot on 26 March 2016, 18:54:23 UTC, committed by Mike Marshall on 08 April 2016, 18:08:38 UTC
fs/orangefs/orangefs-debugfs.c:130:2-26: WARNING: NULL check before freeing functions like kfree, debugfs_remove, debugfs_remove_recursive or usb_free_urb is not needed. Maybe consider reorganizing relevant code to avoid passing NULL values. NULL check before some freeing functions is not needed. Based on checkpatch warning "kfree(NULL) is safe this check is probably not required" and kfreeaddr.cocci by Julia Lawall. Generated by: scripts/coccinelle/free/ifnullfree.cocci Signed-off-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Mike Marshall <hubcap@omnibond.com>
1 parent a9bb3ba
decode_rs.c
/*
* lib/reed_solomon/decode_rs.c
*
* Overview:
* Generic Reed Solomon encoder / decoder library
*
* Copyright 2002, Phil Karn, KA9Q
* May be used under the terms of the GNU General Public License (GPL)
*
* Adaption to the kernel by Thomas Gleixner (tglx@linutronix.de)
*
* $Id: decode_rs.c,v 1.7 2005/11/07 11:14:59 gleixner Exp $
*
*/
/* Generic data width independent code which is included by the
* wrappers.
*/
{
int deg_lambda, el, deg_omega;
int i, j, r, k, pad;
int nn = rs->nn;
int nroots = rs->nroots;
int fcr = rs->fcr;
int prim = rs->prim;
int iprim = rs->iprim;
uint16_t *alpha_to = rs->alpha_to;
uint16_t *index_of = rs->index_of;
uint16_t u, q, tmp, num1, num2, den, discr_r, syn_error;
/* Err+Eras Locator poly and syndrome poly The maximum value
* of nroots is 8. So the necessary stack size will be about
* 220 bytes max.
*/
uint16_t lambda[nroots + 1], syn[nroots];
uint16_t b[nroots + 1], t[nroots + 1], omega[nroots + 1];
uint16_t root[nroots], reg[nroots + 1], loc[nroots];
int count = 0;
uint16_t msk = (uint16_t) rs->nn;
/* Check length parameter for validity */
pad = nn - nroots - len;
BUG_ON(pad < 0 || pad >= nn);
/* Does the caller provide the syndrome ? */
if (s != NULL)
goto decode;
/* form the syndromes; i.e., evaluate data(x) at roots of
* g(x) */
for (i = 0; i < nroots; i++)
syn[i] = (((uint16_t) data[0]) ^ invmsk) & msk;
for (j = 1; j < len; j++) {
for (i = 0; i < nroots; i++) {
if (syn[i] == 0) {
syn[i] = (((uint16_t) data[j]) ^
invmsk) & msk;
} else {
syn[i] = ((((uint16_t) data[j]) ^
invmsk) & msk) ^
alpha_to[rs_modnn(rs, index_of[syn[i]] +
(fcr + i) * prim)];
}
}
}
for (j = 0; j < nroots; j++) {
for (i = 0; i < nroots; i++) {
if (syn[i] == 0) {
syn[i] = ((uint16_t) par[j]) & msk;
} else {
syn[i] = (((uint16_t) par[j]) & msk) ^
alpha_to[rs_modnn(rs, index_of[syn[i]] +
(fcr+i)*prim)];
}
}
}
s = syn;
/* Convert syndromes to index form, checking for nonzero condition */
syn_error = 0;
for (i = 0; i < nroots; i++) {
syn_error |= s[i];
s[i] = index_of[s[i]];
}
if (!syn_error) {
/* if syndrome is zero, data[] is a codeword and there are no
* errors to correct. So return data[] unmodified
*/
count = 0;
goto finish;
}
decode:
memset(&lambda[1], 0, nroots * sizeof(lambda[0]));
lambda[0] = 1;
if (no_eras > 0) {
/* Init lambda to be the erasure locator polynomial */
lambda[1] = alpha_to[rs_modnn(rs,
prim * (nn - 1 - eras_pos[0]))];
for (i = 1; i < no_eras; i++) {
u = rs_modnn(rs, prim * (nn - 1 - eras_pos[i]));
for (j = i + 1; j > 0; j--) {
tmp = index_of[lambda[j - 1]];
if (tmp != nn) {
lambda[j] ^=
alpha_to[rs_modnn(rs, u + tmp)];
}
}
}
}
for (i = 0; i < nroots + 1; i++)
b[i] = index_of[lambda[i]];
/*
* Begin Berlekamp-Massey algorithm to determine error+erasure
* locator polynomial
*/
r = no_eras;
el = no_eras;
while (++r <= nroots) { /* r is the step number */
/* Compute discrepancy at the r-th step in poly-form */
discr_r = 0;
for (i = 0; i < r; i++) {
if ((lambda[i] != 0) && (s[r - i - 1] != nn)) {
discr_r ^=
alpha_to[rs_modnn(rs,
index_of[lambda[i]] +
s[r - i - 1])];
}
}
discr_r = index_of[discr_r]; /* Index form */
if (discr_r == nn) {
/* 2 lines below: B(x) <-- x*B(x) */
memmove (&b[1], b, nroots * sizeof (b[0]));
b[0] = nn;
} else {
/* 7 lines below: T(x) <-- lambda(x)-discr_r*x*b(x) */
t[0] = lambda[0];
for (i = 0; i < nroots; i++) {
if (b[i] != nn) {
t[i + 1] = lambda[i + 1] ^
alpha_to[rs_modnn(rs, discr_r +
b[i])];
} else
t[i + 1] = lambda[i + 1];
}
if (2 * el <= r + no_eras - 1) {
el = r + no_eras - el;
/*
* 2 lines below: B(x) <-- inv(discr_r) *
* lambda(x)
*/
for (i = 0; i <= nroots; i++) {
b[i] = (lambda[i] == 0) ? nn :
rs_modnn(rs, index_of[lambda[i]]
- discr_r + nn);
}
} else {
/* 2 lines below: B(x) <-- x*B(x) */
memmove(&b[1], b, nroots * sizeof(b[0]));
b[0] = nn;
}
memcpy(lambda, t, (nroots + 1) * sizeof(t[0]));
}
}
/* Convert lambda to index form and compute deg(lambda(x)) */
deg_lambda = 0;
for (i = 0; i < nroots + 1; i++) {
lambda[i] = index_of[lambda[i]];
if (lambda[i] != nn)
deg_lambda = i;
}
/* Find roots of error+erasure locator polynomial by Chien search */
memcpy(®[1], &lambda[1], nroots * sizeof(reg[0]));
count = 0; /* Number of roots of lambda(x) */
for (i = 1, k = iprim - 1; i <= nn; i++, k = rs_modnn(rs, k + iprim)) {
q = 1; /* lambda[0] is always 0 */
for (j = deg_lambda; j > 0; j--) {
if (reg[j] != nn) {
reg[j] = rs_modnn(rs, reg[j] + j);
q ^= alpha_to[reg[j]];
}
}
if (q != 0)
continue; /* Not a root */
/* store root (index-form) and error location number */
root[count] = i;
loc[count] = k;
/* If we've already found max possible roots,
* abort the search to save time
*/
if (++count == deg_lambda)
break;
}
if (deg_lambda != count) {
/*
* deg(lambda) unequal to number of roots => uncorrectable
* error detected
*/
count = -EBADMSG;
goto finish;
}
/*
* Compute err+eras evaluator poly omega(x) = s(x)*lambda(x) (modulo
* x**nroots). in index form. Also find deg(omega).
*/
deg_omega = deg_lambda - 1;
for (i = 0; i <= deg_omega; i++) {
tmp = 0;
for (j = i; j >= 0; j--) {
if ((s[i - j] != nn) && (lambda[j] != nn))
tmp ^=
alpha_to[rs_modnn(rs, s[i - j] + lambda[j])];
}
omega[i] = index_of[tmp];
}
/*
* Compute error values in poly-form. num1 = omega(inv(X(l))), num2 =
* inv(X(l))**(fcr-1) and den = lambda_pr(inv(X(l))) all in poly-form
*/
for (j = count - 1; j >= 0; j--) {
num1 = 0;
for (i = deg_omega; i >= 0; i--) {
if (omega[i] != nn)
num1 ^= alpha_to[rs_modnn(rs, omega[i] +
i * root[j])];
}
num2 = alpha_to[rs_modnn(rs, root[j] * (fcr - 1) + nn)];
den = 0;
/* lambda[i+1] for i even is the formal derivative
* lambda_pr of lambda[i] */
for (i = min(deg_lambda, nroots - 1) & ~1; i >= 0; i -= 2) {
if (lambda[i + 1] != nn) {
den ^= alpha_to[rs_modnn(rs, lambda[i + 1] +
i * root[j])];
}
}
/* Apply error to data */
if (num1 != 0 && loc[j] >= pad) {
uint16_t cor = alpha_to[rs_modnn(rs,index_of[num1] +
index_of[num2] +
nn - index_of[den])];
/* Store the error correction pattern, if a
* correction buffer is available */
if (corr) {
corr[j] = cor;
} else {
/* If a data buffer is given and the
* error is inside the message,
* correct it */
if (data && (loc[j] < (nn - nroots)))
data[loc[j] - pad] ^= cor;
}
}
}
finish:
if (eras_pos != NULL) {
for (i = 0; i < count; i++)
eras_pos[i] = loc[i] - pad;
}
return count;
}
![swh spinner](/static/img/swh-spinner.gif)
Computing file changes ...