13  * encoding / decoding of RS codes.
16  * for the given rs parameters. The control struct is unique per instance.
52 /* This list holds all currently allocated rs codec structures */
62  * @fcr:	first root of RS code generator polynomial, index form
64  * @nroots:	RS code generator polynomial degree (number of roots)
74 	struct rs_codec *rs;  in codec_init()  local
76 	rs = kzalloc(sizeof(*rs), gfp);  in codec_init()
77 	if (!rs)  in codec_init()
80 	INIT_LIST_HEAD(&rs->list);  in codec_init()
82 	rs->mm = symsize;  in codec_init()
83 	rs->nn = (1 << symsize) - 1;  in codec_init()
84 	rs->fcr = fcr;  in codec_init()
85 	rs->prim = prim;  in codec_init()
86 	rs->nroots = nroots;  in codec_init()
87 	rs->gfpoly = gfpoly;  in codec_init()
88 	rs->gffunc = gffunc;  in codec_init()
91 	rs->alpha_to = kmalloc_array(rs->nn + 1, sizeof(uint16_t), gfp);  in codec_init()
92 	if (rs->alpha_to == NULL)  in codec_init()
95 	rs->index_of = kmalloc_array(rs->nn + 1, sizeof(uint16_t), gfp);  in codec_init()
96 	if (rs->index_of == NULL)  in codec_init()
99 	rs->genpoly = kmalloc_array(rs->nroots + 1, sizeof(uint16_t), gfp);  in codec_init()
100 	if(rs->genpoly == NULL)  in codec_init()
104 	rs->index_of[0] = rs->nn;	/* log(zero) = -inf */  in codec_init()
105 	rs->alpha_to[rs->nn] = 0;	/* alpha**-inf = 0 */  in codec_init()
108 		for (i = 0; i < rs->nn; i++) {  in codec_init()
109 			rs->index_of[sr] = i;  in codec_init()
110 			rs->alpha_to[i] = sr;  in codec_init()
114 			sr &= rs->nn;  in codec_init()
118 		for (i = 0; i < rs->nn; i++) {  in codec_init()
119 			rs->index_of[sr] = i;  in codec_init()
120 			rs->alpha_to[i] = sr;  in codec_init()
125 	if(sr != rs->alpha_to[0])  in codec_init()
129 	for(iprim = 1; (iprim % prim) != 0; iprim += rs->nn);  in codec_init()
131 	rs->iprim = iprim / prim;  in codec_init()
133 	/* Form RS code generator polynomial from its roots */  in codec_init()
134 	rs->genpoly[0] = 1;  in codec_init()
136 		rs->genpoly[i + 1] = 1;  in codec_init()
137 		/* Multiply rs->genpoly[] by  @**(root + x) */  in codec_init()
139 			if (rs->genpoly[j] != 0) {  in codec_init()
140 				rs->genpoly[j] = rs->genpoly[j -1] ^  in codec_init()
141 					rs->alpha_to[rs_modnn(rs,  in codec_init()
142 					rs->index_of[rs->genpoly[j]] + root)];  in codec_init()
144 				rs->genpoly[j] = rs->genpoly[j - 1];  in codec_init()
146 		/* rs->genpoly[0] can never be zero */  in codec_init()
147 		rs->genpoly[0] =  in codec_init()
148 			rs->alpha_to[rs_modnn(rs,  in codec_init()
149 				rs->index_of[rs->genpoly[0]] + root)];  in codec_init()
151 	/* convert rs->genpoly[] to index form for quicker encoding */  in codec_init()
153 		rs->genpoly[i] = rs->index_of[rs->genpoly[i]];  in codec_init()
155 	rs->users = 1;  in codec_init()
156 	list_add(&rs->list, &codec_list);  in codec_init()
157 	return rs;  in codec_init()
160 	kfree(rs->genpoly);  in codec_init()
161 	kfree(rs->index_of);  in codec_init()
162 	kfree(rs->alpha_to);  in codec_init()
163 	kfree(rs);  in codec_init()
169  *  free_rs - Free the rs control structure
170  *  @rs:	The control structure which is not longer used by the
173  * Free the control structure. If @rs is the last user of the associated
176 void free_rs(struct rs_control *rs)  in free_rs()  argument
180 	if (!rs)  in free_rs()
183 	cd = rs->codec;  in free_rs()
194 	kfree(rs);  in free_rs()
199  * init_rs_internal - Allocate rs control, find a matching codec or allocate a new one
207  *  @fcr:	the first consecutive root of the rs code generator polynomial
210  *  @nroots:	RS code generator polynomial degree (number of roots)
218 	struct rs_control *rs;  in init_rs_internal()  local
237 	rs = kzalloc(sizeof(*rs) + bsize, gfp);  in init_rs_internal()
238 	if (!rs)  in init_rs_internal()
261 		rs->codec = cd;  in init_rs_internal()
266 	rs->codec = codec_init(symsize, gfpoly, gffunc, fcr, prim, nroots, gfp);  in init_rs_internal()
267 	if (!rs->codec) {  in init_rs_internal()
268 		kfree(rs);  in init_rs_internal()
269 		rs = NULL;  in init_rs_internal()
273 	return rs;  in init_rs_internal()
277  * init_rs_gfp - Create a RS control struct and initialize it
282  *  @fcr:	the first consecutive root of the rs code generator polynomial
285  *  @nroots:	RS code generator polynomial degree (number of roots)
296  * init_rs_non_canonical - Allocate rs control struct for fields with
302  *  @fcr:	the first consecutive root of the rs code generator polynomial
305  *  @nroots:	RS code generator polynomial degree (number of roots)
318  *  @rsc:	the rs control structure
339  *  @rsc:	the rs control structure
373  *  @rsc:	the rs control structure
392  *  @rsc:	the rs control structure