305 static inline unsigned int gf_mul(struct bch_control *bch, unsigned int a,  in gf_mul()  argument
308 	return (a && b) ? bch->a_pow_tab[mod_s(bch, bch->a_log_tab[a]+  in gf_mul()
312 static inline unsigned int gf_sqr(struct bch_control *bch, unsigned int a)  in gf_sqr()  argument
314 	return a ? bch->a_pow_tab[mod_s(bch, 2*bch->a_log_tab[a])] : 0;  in gf_sqr()
317 static inline unsigned int gf_div(struct bch_control *bch, unsigned int a,  in gf_div()  argument
320 	return a ? bch->a_pow_tab[mod_s(bch, bch->a_log_tab[a]+  in gf_div()
324 static inline unsigned int gf_inv(struct bch_control *bch, unsigned int a)  in gf_inv()  argument
326 	return bch->a_pow_tab[GF_N(bch)-bch->a_log_tab[a]];  in gf_inv()
518 static int find_affine4_roots(struct bch_control *bch, unsigned int a,  in find_affine4_roots()  argument
527 	k = a_log(bch, a);  in find_affine4_roots()
533 			(a ? bch->a_pow_tab[mod_s(bch, k)] : 0)^  in find_affine4_roots()
616 	unsigned int a, b, c, a2, b2, c2, e3, tmp[4];  in find_poly_deg3_roots()  local
628 		a = gf_sqr(bch, a2)^b2;            /* a = a2^2 + b2 */  in find_poly_deg3_roots()
631 		if (find_affine4_roots(bch, a, b, c, tmp) == 4) {  in find_poly_deg3_roots()
649 	unsigned int a, b, c, d, e = 0, f, a2, b2, c2, e4;  in find_poly_deg4_roots()  local
659 	a = gf_div(bch, poly->c[3], e4);  in find_poly_deg4_roots()
662 	if (a) {  in find_poly_deg4_roots()
666 			f = gf_div(bch, c, a);  in find_poly_deg4_roots()
678 			b = gf_mul(bch, a, e)^b;  in find_poly_deg4_roots()
686 		b2 = gf_div(bch, a, d);  in find_poly_deg4_roots()
698 			f = a ? gf_inv(bch, roots[i]) : roots[i];  in find_poly_deg4_roots()
710 			   const struct gf_poly *a, int *rep)  in gf_poly_logrep()  argument
712 	int i, d = a->deg, l = GF_N(bch)-a_log(bch, a->c[a->deg]);  in gf_poly_logrep()
716 		rep[i] = a->c[i] ? mod_s(bch, a_log(bch, a->c[i])+l) : -1;  in gf_poly_logrep()
722 static void gf_poly_mod(struct bch_control *bch, struct gf_poly *a,  in gf_poly_mod()  argument
726 	unsigned int i, j, *c = a->c;  in gf_poly_mod()
729 	if (a->deg < d)  in gf_poly_mod()
738 	for (j = a->deg; j >= d; j--) {  in gf_poly_mod()
750 	a->deg = d-1;  in gf_poly_mod()
751 	while (!c[a->deg] && a->deg)  in gf_poly_mod()
752 		a->deg--;  in gf_poly_mod()
758 static void gf_poly_div(struct bch_control *bch, struct gf_poly *a,  in gf_poly_div()  argument
761 	if (a->deg >= b->deg) {  in gf_poly_div()
762 		q->deg = a->deg-b->deg;  in gf_poly_div()
764 		gf_poly_mod(bch, a, b, NULL);  in gf_poly_div()
766 		memcpy(q->c, &a->c[b->deg], (1+q->deg)*sizeof(unsigned int));  in gf_poly_div()
776 static struct gf_poly *gf_poly_gcd(struct bch_control *bch, struct gf_poly *a,  in gf_poly_gcd()  argument
781 	dbg("gcd(%s,%s)=", gf_poly_str(a), gf_poly_str(b));  in gf_poly_gcd()
783 	if (a->deg < b->deg) {  in gf_poly_gcd()
785 		b = a;  in gf_poly_gcd()
786 		a = tmp;  in gf_poly_gcd()
790 		gf_poly_mod(bch, a, b, NULL);  in gf_poly_gcd()
792 		b = a;  in gf_poly_gcd()
793 		a = tmp;  in gf_poly_gcd()
796 	dbg("%s\n", gf_poly_str(a));  in gf_poly_gcd()
798 	return a;  in gf_poly_gcd()