Refactors rslib and callers to provide a per-instance allocation area
instead of performing VLAs on the stack. -----BEGIN PGP SIGNATURE----- Comment: Kees Cook <kees@outflux.net> iQJKBAABCgA0FiEEpcP2jyKd1g9yPm4TiXL039xtwCYFAlsUv+MWHGtlZXNjb29r QGNocm9taXVtLm9yZwAKCRCJcvTf3G3AJsL4D/0arl2+HZtG3GV6zMHbH1T3J0a3 mZojEEZqgByx0vlN/Ai57YK4ADHKlF3oYqpXamc718iAmDfKgvbdG+IPv6hg0MQR c6F+ogSbcZ38vY7t08Iaa9cBQcKFJwJGAbYXyKV6dKp0ddPqNBBxHG0CLSWL+3DE ZxKRKQFQKZWJR587CjA9geZOImgYJG8Jq9Ue4fp1fKacBEBiZTtI/Y8C4XlrxZz6 6p7BdarMXKqxW8B8vpE4xfCCkm8QGAfEuAXzMrqFLZhj48bg7+Tqd3d4AHm28hMp Q2eHyS9j4wWN+OxA1R+VIuzciz/vfWZJi1N7zSV8LznPPLICX8Vl4gXw+MkrELYV vzZRlRH67E993bsj0Xp65w7Zwc3MJKVfJOUq+3qR3I1JytCSOBsLs2w/VE2bzpeO jFD4gUJxYnl5s2UnCiHVgUzbgXE/n+JQS3Acf71qfAsb+Ld2/q9Tyjx7p7sm5IfB m/lokrSgBajtHPZfB6pQV2AvaoLIbWW9Lf1p84zA6XAwdAnAESffUGQHEK/W02a7 ftwxXnOvjgRZJ/lUfOb0GQDgQniXO7cN7AcmKAfL+DNZb0j86esR6PuZDCIeDhTJ KcTVcwPtFnI4W+H3vagh+mLHf7bL/RgLngjUZd6PHqS+cVQfKFiNe43zlRl9+eRj U20+w5VfwSkrmAgfSw== =Z1if -----END PGP SIGNATURE----- Merge tag 'rslib-v4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull reed-salomon library updates from Kees Cook: "Refactors rslib and callers to provide a per-instance allocation area instead of performing VLAs on the stack" * tag 'rslib-v4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: rslib: Allocate decoder buffers to avoid VLAs mtd: rawnand: diskonchip: Allocate rs control per instance rslib: Split rs control struct rslib: Simplify error path rslib: Remove GPL boilerplate rslib: Add SPDX identifiers rslib: Cleanup top level comments rslib: Cleanup whitespace damage dm/verity_fec: Use GFP aware reed solomon init rslib: Add GFP aware init function
This commit is contained in:
Linus Torvalds
Коммит
25d80be86c
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@ -570,7 +570,7 @@ static void *fec_rs_alloc(gfp_t gfp_mask, void *pool_data)
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{
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struct dm_verity *v = (struct dm_verity *)pool_data;
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return init_rs(8, 0x11d, 0, 1, v->fec->roots);
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return init_rs_gfp(8, 0x11d, 0, 1, v->fec->roots, gfp_mask);
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}
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static void fec_rs_free(void *element, void *pool_data)
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@ -394,12 +394,13 @@ static int cafe_nand_read_page(struct mtd_info *mtd, struct nand_chip *chip,
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for (i=0; i<8; i+=2) {
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uint32_t tmp = cafe_readl(cafe, NAND_ECC_SYN01 + (i*2));
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syn[i] = cafe->rs->index_of[tmp & 0xfff];
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syn[i+1] = cafe->rs->index_of[(tmp >> 16) & 0xfff];
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syn[i] = cafe->rs->codec->index_of[tmp & 0xfff];
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syn[i+1] = cafe->rs->codec->index_of[(tmp >> 16) & 0xfff];
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}
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n = decode_rs16(cafe->rs, NULL, NULL, 1367, syn, 0, pos, 0,
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pat);
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pat);
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for (i = 0; i < n; i++) {
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int p = pos[i];
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@ -66,6 +66,7 @@ struct doc_priv {
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int curchip;
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int mh0_page;
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int mh1_page;
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struct rs_control *rs_decoder;
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struct mtd_info *nextdoc;
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/* Handle the last stage of initialization (BBT scan, partitioning) */
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@ -123,9 +124,6 @@ MODULE_PARM_DESC(doc_config_location, "Physical memory address at which to probe
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/* Number of symbols */
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#define NN 1023
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/* the Reed Solomon control structure */
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static struct rs_control *rs_decoder;
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/*
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* The HW decoder in the DoC ASIC's provides us a error syndrome,
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* which we must convert to a standard syndrome usable by the generic
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@ -140,6 +138,7 @@ static int doc_ecc_decode(struct rs_control *rs, uint8_t *data, uint8_t *ecc)
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int i, j, nerr, errpos[8];
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uint8_t parity;
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uint16_t ds[4], s[5], tmp, errval[8], syn[4];
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struct rs_codec *cd = rs->codec;
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memset(syn, 0, sizeof(syn));
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/* Convert the ecc bytes into words */
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@ -160,15 +159,15 @@ static int doc_ecc_decode(struct rs_control *rs, uint8_t *data, uint8_t *ecc)
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for (j = 1; j < NROOTS; j++) {
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if (ds[j] == 0)
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continue;
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tmp = rs->index_of[ds[j]];
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tmp = cd->index_of[ds[j]];
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for (i = 0; i < NROOTS; i++)
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s[i] ^= rs->alpha_to[rs_modnn(rs, tmp + (FCR + i) * j)];
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s[i] ^= cd->alpha_to[rs_modnn(cd, tmp + (FCR + i) * j)];
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}
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/* Calc syn[i] = s[i] / alpha^(v + i) */
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for (i = 0; i < NROOTS; i++) {
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if (s[i])
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syn[i] = rs_modnn(rs, rs->index_of[s[i]] + (NN - FCR - i));
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syn[i] = rs_modnn(cd, cd->index_of[s[i]] + (NN - FCR - i));
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}
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/* Call the decoder library */
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nerr = decode_rs16(rs, NULL, NULL, 1019, syn, 0, errpos, 0, errval);
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@ -930,7 +929,7 @@ static int doc200x_correct_data(struct mtd_info *mtd, u_char *dat,
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calc_ecc[i] = ReadDOC_(docptr, DoC_ECCSyndrome0 + i);
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}
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ret = doc_ecc_decode(rs_decoder, dat, calc_ecc);
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ret = doc_ecc_decode(doc->rs_decoder, dat, calc_ecc);
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if (ret > 0)
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pr_err("doc200x_correct_data corrected %d errors\n",
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ret);
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@ -1421,10 +1420,10 @@ static inline int __init doc2001plus_init(struct mtd_info *mtd)
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static int __init doc_probe(unsigned long physadr)
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{
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struct nand_chip *nand = NULL;
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struct doc_priv *doc = NULL;
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unsigned char ChipID;
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struct mtd_info *mtd;
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struct nand_chip *nand;
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struct doc_priv *doc;
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void __iomem *virtadr;
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unsigned char save_control;
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unsigned char tmp, tmpb, tmpc;
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@ -1561,8 +1560,25 @@ static int __init doc_probe(unsigned long physadr)
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goto fail;
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}
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/*
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* Allocate a RS codec instance
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*
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* Symbolsize is 10 (bits)
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* Primitve polynomial is x^10+x^3+1
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* First consecutive root is 510
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* Primitve element to generate roots = 1
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* Generator polinomial degree = 4
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*/
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doc = (struct doc_priv *) (nand + 1);
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doc->rs_decoder = init_rs(10, 0x409, FCR, 1, NROOTS);
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if (!doc->rs_decoder) {
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pr_err("DiskOnChip: Could not create a RS codec\n");
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ret = -ENOMEM;
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goto fail;
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}
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mtd = nand_to_mtd(nand);
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doc = (struct doc_priv *) (nand + 1);
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nand->bbt_td = (struct nand_bbt_descr *) (doc + 1);
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nand->bbt_md = nand->bbt_td + 1;
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@ -1612,7 +1628,6 @@ static int __init doc_probe(unsigned long physadr)
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haven't yet added it. This is handled without incident by
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mtd_device_unregister, as far as I can tell. */
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nand_release(mtd);
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kfree(nand);
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goto fail;
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}
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@ -1625,6 +1640,9 @@ static int __init doc_probe(unsigned long physadr)
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actually a DiskOnChip. */
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WriteDOC(save_control, virtadr, DOCControl);
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fail:
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if (doc)
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free_rs(doc->rs_decoder);
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kfree(nand);
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iounmap(virtadr);
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error_ioremap:
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@ -1647,6 +1665,7 @@ static void release_nanddoc(void)
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nand_release(mtd);
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iounmap(doc->virtadr);
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release_mem_region(doc->physadr, DOC_IOREMAP_LEN);
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free_rs(doc->rs_decoder);
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kfree(nand);
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}
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}
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@ -1655,27 +1674,12 @@ static int __init init_nanddoc(void)
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{
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int i, ret = 0;
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/* We could create the decoder on demand, if memory is a concern.
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* This way we have it handy, if an error happens
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*
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* Symbolsize is 10 (bits)
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* Primitve polynomial is x^10+x^3+1
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* first consecutive root is 510
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* primitve element to generate roots = 1
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* generator polinomial degree = 4
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*/
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rs_decoder = init_rs(10, 0x409, FCR, 1, NROOTS);
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if (!rs_decoder) {
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pr_err("DiskOnChip: Could not create a RS decoder\n");
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return -ENOMEM;
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}
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if (doc_config_location) {
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pr_info("Using configured DiskOnChip probe address 0x%lx\n",
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doc_config_location);
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ret = doc_probe(doc_config_location);
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if (ret < 0)
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goto outerr;
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return ret;
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} else {
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for (i = 0; (doc_locations[i] != 0xffffffff); i++) {
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doc_probe(doc_locations[i]);
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@ -1686,11 +1690,7 @@ static int __init init_nanddoc(void)
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if (!doclist) {
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pr_info("No valid DiskOnChip devices found\n");
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ret = -ENODEV;
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goto outerr;
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}
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return 0;
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outerr:
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free_rs(rs_decoder);
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return ret;
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}
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@ -1698,11 +1698,6 @@ static void __exit cleanup_nanddoc(void)
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{
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/* Cleanup the nand/DoC resources */
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release_nanddoc();
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/* Free the reed solomon resources */
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if (rs_decoder) {
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free_rs(rs_decoder);
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}
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}
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module_init(init_nanddoc);
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@ -1,28 +1,21 @@
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// SPDX-License-Identifier: GPL-2.0
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/*
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* include/linux/rslib.h
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*
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* Overview:
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* Generic Reed Solomon encoder / decoder library
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* Generic Reed Solomon encoder / decoder library
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*
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* Copyright (C) 2004 Thomas Gleixner (tglx@linutronix.de)
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*
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* RS code lifted from reed solomon library written by Phil Karn
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* Copyright 2002 Phil Karn, KA9Q
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*
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* $Id: rslib.h,v 1.4 2005/11/07 11:14:52 gleixner Exp $
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#ifndef _RSLIB_H_
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#define _RSLIB_H_
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#include <linux/list.h>
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#include <linux/types.h> /* for gfp_t */
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#include <linux/gfp.h> /* for GFP_KERNEL */
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/**
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* struct rs_control - rs control structure
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* struct rs_codec - rs codec data
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*
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* @mm: Bits per symbol
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* @nn: Symbols per block (= (1<<mm)-1)
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@ -36,24 +29,34 @@
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* @gfpoly: The primitive generator polynominal
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* @gffunc: Function to generate the field, if non-canonical representation
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* @users: Users of this structure
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* @list: List entry for the rs control list
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* @list: List entry for the rs codec list
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*/
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struct rs_control {
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int mm;
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int nn;
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struct rs_codec {
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int mm;
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int nn;
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uint16_t *alpha_to;
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uint16_t *index_of;
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uint16_t *genpoly;
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int nroots;
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int fcr;
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int prim;
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int iprim;
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int nroots;
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int fcr;
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int prim;
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int iprim;
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int gfpoly;
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int (*gffunc)(int);
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int users;
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struct list_head list;
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};
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/**
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* struct rs_control - rs control structure per instance
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* @codec: The codec used for this instance
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* @buffers: Internal scratch buffers used in calls to decode_rs()
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*/
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struct rs_control {
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struct rs_codec *codec;
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uint16_t buffers[0];
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};
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/* General purpose RS codec, 8-bit data width, symbol width 1-15 bit */
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#ifdef CONFIG_REED_SOLOMON_ENC8
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int encode_rs8(struct rs_control *rs, uint8_t *data, int len, uint16_t *par,
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@ -76,18 +79,37 @@ int decode_rs16(struct rs_control *rs, uint16_t *data, uint16_t *par, int len,
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uint16_t *corr);
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#endif
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/* Create or get a matching rs control structure */
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struct rs_control *init_rs(int symsize, int gfpoly, int fcr, int prim,
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int nroots);
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struct rs_control *init_rs_gfp(int symsize, int gfpoly, int fcr, int prim,
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int nroots, gfp_t gfp);
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/**
|
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* init_rs - Create a RS control struct and initialize it
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* @symsize: the symbol size (number of bits)
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* @gfpoly: the extended Galois field generator polynomial coefficients,
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* with the 0th coefficient in the low order bit. The polynomial
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* must be primitive;
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* @fcr: the first consecutive root of the rs code generator polynomial
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* in index form
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* @prim: primitive element to generate polynomial roots
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* @nroots: RS code generator polynomial degree (number of roots)
|
||||
*
|
||||
* Allocations use GFP_KERNEL.
|
||||
*/
|
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static inline struct rs_control *init_rs(int symsize, int gfpoly, int fcr,
|
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int prim, int nroots)
|
||||
{
|
||||
return init_rs_gfp(symsize, gfpoly, fcr, prim, nroots, GFP_KERNEL);
|
||||
}
|
||||
|
||||
struct rs_control *init_rs_non_canonical(int symsize, int (*func)(int),
|
||||
int fcr, int prim, int nroots);
|
||||
int fcr, int prim, int nroots);
|
||||
|
||||
/* Release a rs control structure */
|
||||
void free_rs(struct rs_control *rs);
|
||||
|
||||
/** modulo replacement for galois field arithmetics
|
||||
*
|
||||
* @rs: the rs control structure
|
||||
* @rs: Pointer to the RS codec
|
||||
* @x: the value to reduce
|
||||
*
|
||||
* where
|
||||
|
|
@ -97,7 +119,7 @@ void free_rs(struct rs_control *rs);
|
|||
* Simple arithmetic modulo would return a wrong result for values
|
||||
* >= 3 * rs->nn
|
||||
*/
|
||||
static inline int rs_modnn(struct rs_control *rs, int x)
|
||||
static inline int rs_modnn(struct rs_codec *rs, int x)
|
||||
{
|
||||
while (x >= rs->nn) {
|
||||
x -= rs->nn;
|
||||
|
|
|
|||
|
|
@ -1,22 +1,16 @@
|
|||
// SPDX-License-Identifier: GPL-2.0
|
||||
/*
|
||||
* lib/reed_solomon/decode_rs.c
|
||||
*
|
||||
* Overview:
|
||||
* Generic Reed Solomon encoder / decoder library
|
||||
* 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.
|
||||
* Generic data width independent code which is included by the wrappers.
|
||||
*/
|
||||
{
|
||||
struct rs_codec *rs = rsc->codec;
|
||||
int deg_lambda, el, deg_omega;
|
||||
int i, j, r, k, pad;
|
||||
int nn = rs->nn;
|
||||
|
|
@ -27,16 +21,22 @@
|
|||
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;
|
||||
|
||||
/*
|
||||
* The decoder buffers are in the rs control struct. They are
|
||||
* arrays sized [nroots + 1]
|
||||
*/
|
||||
uint16_t *lambda = rsc->buffers + RS_DECODE_LAMBDA * (nroots + 1);
|
||||
uint16_t *syn = rsc->buffers + RS_DECODE_SYN * (nroots + 1);
|
||||
uint16_t *b = rsc->buffers + RS_DECODE_B * (nroots + 1);
|
||||
uint16_t *t = rsc->buffers + RS_DECODE_T * (nroots + 1);
|
||||
uint16_t *omega = rsc->buffers + RS_DECODE_OMEGA * (nroots + 1);
|
||||
uint16_t *root = rsc->buffers + RS_DECODE_ROOT * (nroots + 1);
|
||||
uint16_t *reg = rsc->buffers + RS_DECODE_REG * (nroots + 1);
|
||||
uint16_t *loc = rsc->buffers + RS_DECODE_LOC * (nroots + 1);
|
||||
|
||||
/* Check length parameter for validity */
|
||||
pad = nn - nroots - len;
|
||||
BUG_ON(pad < 0 || pad >= nn);
|
||||
|
|
|
|||
|
|
@ -1,23 +1,16 @@
|
|||
// SPDX-License-Identifier: GPL-2.0
|
||||
/*
|
||||
* lib/reed_solomon/encode_rs.c
|
||||
*
|
||||
* Overview:
|
||||
* Generic Reed Solomon encoder / decoder library
|
||||
* 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: encode_rs.c,v 1.5 2005/11/07 11:14:59 gleixner Exp $
|
||||
*
|
||||
*/
|
||||
|
||||
/* Generic data width independent code which is included by the
|
||||
* wrappers.
|
||||
* int encode_rsX (struct rs_control *rs, uintX_t *data, int len, uintY_t *par)
|
||||
* Generic data width independent code which is included by the wrappers.
|
||||
*/
|
||||
{
|
||||
struct rs_codec *rs = rsc->codec;
|
||||
int i, j, pad;
|
||||
int nn = rs->nn;
|
||||
int nroots = rs->nroots;
|
||||
|
|
|
|||
|
|
@ -1,43 +1,34 @@
|
|||
// SPDX-License-Identifier: GPL-2.0
|
||||
/*
|
||||
* lib/reed_solomon/reed_solomon.c
|
||||
*
|
||||
* Overview:
|
||||
* Generic Reed Solomon encoder / decoder library
|
||||
* Generic Reed Solomon encoder / decoder library
|
||||
*
|
||||
* Copyright (C) 2004 Thomas Gleixner (tglx@linutronix.de)
|
||||
*
|
||||
* Reed Solomon code lifted from reed solomon library written by Phil Karn
|
||||
* Copyright 2002 Phil Karn, KA9Q
|
||||
*
|
||||
* $Id: rslib.c,v 1.7 2005/11/07 11:14:59 gleixner Exp $
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify
|
||||
* it under the terms of the GNU General Public License version 2 as
|
||||
* published by the Free Software Foundation.
|
||||
*
|
||||
* Description:
|
||||
*
|
||||
* The generic Reed Solomon library provides runtime configurable
|
||||
* encoding / decoding of RS codes.
|
||||
* Each user must call init_rs to get a pointer to a rs_control
|
||||
* structure for the given rs parameters. This structure is either
|
||||
* generated or a already available matching control structure is used.
|
||||
* If a structure is generated then the polynomial arrays for
|
||||
* fast encoding / decoding are built. This can take some time so
|
||||
* make sure not to call this function from a time critical path.
|
||||
* Usually a module / driver should initialize the necessary
|
||||
* rs_control structure on module / driver init and release it
|
||||
* on exit.
|
||||
* The encoding puts the calculated syndrome into a given syndrome
|
||||
* buffer.
|
||||
* The decoding is a two step process. The first step calculates
|
||||
* the syndrome over the received (data + syndrome) and calls the
|
||||
* second stage, which does the decoding / error correction itself.
|
||||
* Many hw encoders provide a syndrome calculation over the received
|
||||
* data + syndrome and can call the second stage directly.
|
||||
*
|
||||
* Each user must call init_rs to get a pointer to a rs_control structure
|
||||
* for the given rs parameters. The control struct is unique per instance.
|
||||
* It points to a codec which can be shared by multiple control structures.
|
||||
* If a codec is newly allocated then the polynomial arrays for fast
|
||||
* encoding / decoding are built. This can take some time so make sure not
|
||||
* to call this function from a time critical path. Usually a module /
|
||||
* driver should initialize the necessary rs_control structure on module /
|
||||
* driver init and release it on exit.
|
||||
*
|
||||
* The encoding puts the calculated syndrome into a given syndrome buffer.
|
||||
*
|
||||
* The decoding is a two step process. The first step calculates the
|
||||
* syndrome over the received (data + syndrome) and calls the second stage,
|
||||
* which does the decoding / error correction itself. Many hw encoders
|
||||
* provide a syndrome calculation over the received data + syndrome and can
|
||||
* call the second stage directly.
|
||||
*/
|
||||
|
||||
#include <linux/errno.h>
|
||||
#include <linux/kernel.h>
|
||||
#include <linux/init.h>
|
||||
|
|
@ -46,32 +37,44 @@
|
|||
#include <linux/slab.h>
|
||||
#include <linux/mutex.h>
|
||||
|
||||
/* This list holds all currently allocated rs control structures */
|
||||
static LIST_HEAD (rslist);
|
||||
enum {
|
||||
RS_DECODE_LAMBDA,
|
||||
RS_DECODE_SYN,
|
||||
RS_DECODE_B,
|
||||
RS_DECODE_T,
|
||||
RS_DECODE_OMEGA,
|
||||
RS_DECODE_ROOT,
|
||||
RS_DECODE_REG,
|
||||
RS_DECODE_LOC,
|
||||
RS_DECODE_NUM_BUFFERS
|
||||
};
|
||||
|
||||
/* This list holds all currently allocated rs codec structures */
|
||||
static LIST_HEAD(codec_list);
|
||||
/* Protection for the list */
|
||||
static DEFINE_MUTEX(rslistlock);
|
||||
|
||||
/**
|
||||
* rs_init - Initialize a Reed-Solomon codec
|
||||
* codec_init - Initialize a Reed-Solomon codec
|
||||
* @symsize: symbol size, bits (1-8)
|
||||
* @gfpoly: Field generator polynomial coefficients
|
||||
* @gffunc: Field generator function
|
||||
* @fcr: first root of RS code generator polynomial, index form
|
||||
* @prim: primitive element to generate polynomial roots
|
||||
* @nroots: RS code generator polynomial degree (number of roots)
|
||||
* @gfp: GFP_ flags for allocations
|
||||
*
|
||||
* Allocate a control structure and the polynom arrays for faster
|
||||
* Allocate a codec structure and the polynom arrays for faster
|
||||
* en/decoding. Fill the arrays according to the given parameters.
|
||||
*/
|
||||
static struct rs_control *rs_init(int symsize, int gfpoly, int (*gffunc)(int),
|
||||
int fcr, int prim, int nroots)
|
||||
static struct rs_codec *codec_init(int symsize, int gfpoly, int (*gffunc)(int),
|
||||
int fcr, int prim, int nroots, gfp_t gfp)
|
||||
{
|
||||
struct rs_control *rs;
|
||||
int i, j, sr, root, iprim;
|
||||
struct rs_codec *rs;
|
||||
|
||||
/* Allocate the control structure */
|
||||
rs = kmalloc(sizeof (struct rs_control), GFP_KERNEL);
|
||||
if (rs == NULL)
|
||||
rs = kzalloc(sizeof(*rs), gfp);
|
||||
if (!rs)
|
||||
return NULL;
|
||||
|
||||
INIT_LIST_HEAD(&rs->list);
|
||||
|
|
@ -85,17 +88,17 @@ static struct rs_control *rs_init(int symsize, int gfpoly, int (*gffunc)(int),
|
|||
rs->gffunc = gffunc;
|
||||
|
||||
/* Allocate the arrays */
|
||||
rs->alpha_to = kmalloc(sizeof(uint16_t) * (rs->nn + 1), GFP_KERNEL);
|
||||
rs->alpha_to = kmalloc(sizeof(uint16_t) * (rs->nn + 1), gfp);
|
||||
if (rs->alpha_to == NULL)
|
||||
goto errrs;
|
||||
goto err;
|
||||
|
||||
rs->index_of = kmalloc(sizeof(uint16_t) * (rs->nn + 1), GFP_KERNEL);
|
||||
rs->index_of = kmalloc(sizeof(uint16_t) * (rs->nn + 1), gfp);
|
||||
if (rs->index_of == NULL)
|
||||
goto erralp;
|
||||
goto err;
|
||||
|
||||
rs->genpoly = kmalloc(sizeof(uint16_t) * (rs->nroots + 1), GFP_KERNEL);
|
||||
rs->genpoly = kmalloc(sizeof(uint16_t) * (rs->nroots + 1), gfp);
|
||||
if(rs->genpoly == NULL)
|
||||
goto erridx;
|
||||
goto err;
|
||||
|
||||
/* Generate Galois field lookup tables */
|
||||
rs->index_of[0] = rs->nn; /* log(zero) = -inf */
|
||||
|
|
@ -120,7 +123,7 @@ static struct rs_control *rs_init(int symsize, int gfpoly, int (*gffunc)(int),
|
|||
}
|
||||
/* If it's not primitive, exit */
|
||||
if(sr != rs->alpha_to[0])
|
||||
goto errpol;
|
||||
goto err;
|
||||
|
||||
/* Find prim-th root of 1, used in decoding */
|
||||
for(iprim = 1; (iprim % prim) != 0; iprim += rs->nn);
|
||||
|
|
@ -148,42 +151,52 @@ static struct rs_control *rs_init(int symsize, int gfpoly, int (*gffunc)(int),
|
|||
/* convert rs->genpoly[] to index form for quicker encoding */
|
||||
for (i = 0; i <= nroots; i++)
|
||||
rs->genpoly[i] = rs->index_of[rs->genpoly[i]];
|
||||
|
||||
rs->users = 1;
|
||||
list_add(&rs->list, &codec_list);
|
||||
return rs;
|
||||
|
||||
/* Error exit */
|
||||
errpol:
|
||||
err:
|
||||
kfree(rs->genpoly);
|
||||
erridx:
|
||||
kfree(rs->index_of);
|
||||
erralp:
|
||||
kfree(rs->alpha_to);
|
||||
errrs:
|
||||
kfree(rs);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
|
||||
/**
|
||||
* free_rs - Free the rs control structure, if it is no longer used
|
||||
* @rs: the control structure which is not longer used by the
|
||||
* free_rs - Free the rs control structure
|
||||
* @rs: The control structure which is not longer used by the
|
||||
* caller
|
||||
*
|
||||
* Free the control structure. If @rs is the last user of the associated
|
||||
* codec, free the codec as well.
|
||||
*/
|
||||
void free_rs(struct rs_control *rs)
|
||||
{
|
||||
struct rs_codec *cd;
|
||||
|
||||
if (!rs)
|
||||
return;
|
||||
|
||||
cd = rs->codec;
|
||||
mutex_lock(&rslistlock);
|
||||
rs->users--;
|
||||
if(!rs->users) {
|
||||
list_del(&rs->list);
|
||||
kfree(rs->alpha_to);
|
||||
kfree(rs->index_of);
|
||||
kfree(rs->genpoly);
|
||||
kfree(rs);
|
||||
cd->users--;
|
||||
if(!cd->users) {
|
||||
list_del(&cd->list);
|
||||
kfree(cd->alpha_to);
|
||||
kfree(cd->index_of);
|
||||
kfree(cd->genpoly);
|
||||
kfree(cd);
|
||||
}
|
||||
mutex_unlock(&rslistlock);
|
||||
kfree(rs);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(free_rs);
|
||||
|
||||
/**
|
||||
* init_rs_internal - Find a matching or allocate a new rs control structure
|
||||
* init_rs_internal - Allocate rs control, find a matching codec or allocate a new one
|
||||
* @symsize: the symbol size (number of bits)
|
||||
* @gfpoly: the extended Galois field generator polynomial coefficients,
|
||||
* with the 0th coefficient in the low order bit. The polynomial
|
||||
|
|
@ -191,55 +204,69 @@ void free_rs(struct rs_control *rs)
|
|||
* @gffunc: pointer to function to generate the next field element,
|
||||
* or the multiplicative identity element if given 0. Used
|
||||
* instead of gfpoly if gfpoly is 0
|
||||
* @fcr: the first consecutive root of the rs code generator polynomial
|
||||
* @fcr: the first consecutive root of the rs code generator polynomial
|
||||
* in index form
|
||||
* @prim: primitive element to generate polynomial roots
|
||||
* @nroots: RS code generator polynomial degree (number of roots)
|
||||
* @gfp: GFP_ flags for allocations
|
||||
*/
|
||||
static struct rs_control *init_rs_internal(int symsize, int gfpoly,
|
||||
int (*gffunc)(int), int fcr,
|
||||
int prim, int nroots)
|
||||
int (*gffunc)(int), int fcr,
|
||||
int prim, int nroots, gfp_t gfp)
|
||||
{
|
||||
struct list_head *tmp;
|
||||
struct rs_control *rs;
|
||||
struct list_head *tmp;
|
||||
struct rs_control *rs;
|
||||
unsigned int bsize;
|
||||
|
||||
/* Sanity checks */
|
||||
if (symsize < 1)
|
||||
return NULL;
|
||||
if (fcr < 0 || fcr >= (1<<symsize))
|
||||
return NULL;
|
||||
return NULL;
|
||||
if (prim <= 0 || prim >= (1<<symsize))
|
||||
return NULL;
|
||||
return NULL;
|
||||
if (nroots < 0 || nroots >= (1<<symsize))
|
||||
return NULL;
|
||||
|
||||
/*
|
||||
* The decoder needs buffers in each control struct instance to
|
||||
* avoid variable size or large fixed size allocations on
|
||||
* stack. Size the buffers to arrays of [nroots + 1].
|
||||
*/
|
||||
bsize = sizeof(uint16_t) * RS_DECODE_NUM_BUFFERS * (nroots + 1);
|
||||
rs = kzalloc(sizeof(*rs) + bsize, gfp);
|
||||
if (!rs)
|
||||
return NULL;
|
||||
|
||||
mutex_lock(&rslistlock);
|
||||
|
||||
/* Walk through the list and look for a matching entry */
|
||||
list_for_each(tmp, &rslist) {
|
||||
rs = list_entry(tmp, struct rs_control, list);
|
||||
if (symsize != rs->mm)
|
||||
list_for_each(tmp, &codec_list) {
|
||||
struct rs_codec *cd = list_entry(tmp, struct rs_codec, list);
|
||||
|
||||
if (symsize != cd->mm)
|
||||
continue;
|
||||
if (gfpoly != rs->gfpoly)
|
||||
if (gfpoly != cd->gfpoly)
|
||||
continue;
|
||||
if (gffunc != rs->gffunc)
|
||||
if (gffunc != cd->gffunc)
|
||||
continue;
|
||||
if (fcr != rs->fcr)
|
||||
if (fcr != cd->fcr)
|
||||
continue;
|
||||
if (prim != rs->prim)
|
||||
if (prim != cd->prim)
|
||||
continue;
|
||||
if (nroots != rs->nroots)
|
||||
if (nroots != cd->nroots)
|
||||
continue;
|
||||
/* We have a matching one already */
|
||||
rs->users++;
|
||||
cd->users++;
|
||||
rs->codec = cd;
|
||||
goto out;
|
||||
}
|
||||
|
||||
/* Create a new one */
|
||||
rs = rs_init(symsize, gfpoly, gffunc, fcr, prim, nroots);
|
||||
if (rs) {
|
||||
rs->users = 1;
|
||||
list_add(&rs->list, &rslist);
|
||||
rs->codec = codec_init(symsize, gfpoly, gffunc, fcr, prim, nroots, gfp);
|
||||
if (!rs->codec) {
|
||||
kfree(rs);
|
||||
rs = NULL;
|
||||
}
|
||||
out:
|
||||
mutex_unlock(&rslistlock);
|
||||
|
|
@ -247,45 +274,48 @@ out:
|
|||
}
|
||||
|
||||
/**
|
||||
* init_rs - Find a matching or allocate a new rs control structure
|
||||
* init_rs_gfp - Create a RS control struct and initialize it
|
||||
* @symsize: the symbol size (number of bits)
|
||||
* @gfpoly: the extended Galois field generator polynomial coefficients,
|
||||
* with the 0th coefficient in the low order bit. The polynomial
|
||||
* must be primitive;
|
||||
* @fcr: the first consecutive root of the rs code generator polynomial
|
||||
* @fcr: the first consecutive root of the rs code generator polynomial
|
||||
* in index form
|
||||
* @prim: primitive element to generate polynomial roots
|
||||
* @nroots: RS code generator polynomial degree (number of roots)
|
||||
* @gfp: GFP_ flags for allocations
|
||||
*/
|
||||
struct rs_control *init_rs(int symsize, int gfpoly, int fcr, int prim,
|
||||
int nroots)
|
||||
struct rs_control *init_rs_gfp(int symsize, int gfpoly, int fcr, int prim,
|
||||
int nroots, gfp_t gfp)
|
||||
{
|
||||
return init_rs_internal(symsize, gfpoly, NULL, fcr, prim, nroots);
|
||||
return init_rs_internal(symsize, gfpoly, NULL, fcr, prim, nroots, gfp);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(init_rs_gfp);
|
||||
|
||||
/**
|
||||
* init_rs_non_canonical - Find a matching or allocate a new rs control
|
||||
* structure, for fields with non-canonical
|
||||
* representation
|
||||
* init_rs_non_canonical - Allocate rs control struct for fields with
|
||||
* non-canonical representation
|
||||
* @symsize: the symbol size (number of bits)
|
||||
* @gffunc: pointer to function to generate the next field element,
|
||||
* or the multiplicative identity element if given 0. Used
|
||||
* instead of gfpoly if gfpoly is 0
|
||||
* @fcr: the first consecutive root of the rs code generator polynomial
|
||||
* @fcr: the first consecutive root of the rs code generator polynomial
|
||||
* in index form
|
||||
* @prim: primitive element to generate polynomial roots
|
||||
* @nroots: RS code generator polynomial degree (number of roots)
|
||||
*/
|
||||
struct rs_control *init_rs_non_canonical(int symsize, int (*gffunc)(int),
|
||||
int fcr, int prim, int nroots)
|
||||
int fcr, int prim, int nroots)
|
||||
{
|
||||
return init_rs_internal(symsize, 0, gffunc, fcr, prim, nroots);
|
||||
return init_rs_internal(symsize, 0, gffunc, fcr, prim, nroots,
|
||||
GFP_KERNEL);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(init_rs_non_canonical);
|
||||
|
||||
#ifdef CONFIG_REED_SOLOMON_ENC8
|
||||
/**
|
||||
* encode_rs8 - Calculate the parity for data values (8bit data width)
|
||||
* @rs: the rs control structure
|
||||
* @rsc: the rs control structure
|
||||
* @data: data field of a given type
|
||||
* @len: data length
|
||||
* @par: parity data, must be initialized by caller (usually all 0)
|
||||
|
|
@ -295,7 +325,7 @@ struct rs_control *init_rs_non_canonical(int symsize, int (*gffunc)(int),
|
|||
* symbol size > 8. The calling code must take care of encoding of the
|
||||
* syndrome result for storage itself.
|
||||
*/
|
||||
int encode_rs8(struct rs_control *rs, uint8_t *data, int len, uint16_t *par,
|
||||
int encode_rs8(struct rs_control *rsc, uint8_t *data, int len, uint16_t *par,
|
||||
uint16_t invmsk)
|
||||
{
|
||||
#include "encode_rs.c"
|
||||
|
|
@ -306,7 +336,7 @@ EXPORT_SYMBOL_GPL(encode_rs8);
|
|||
#ifdef CONFIG_REED_SOLOMON_DEC8
|
||||
/**
|
||||
* decode_rs8 - Decode codeword (8bit data width)
|
||||
* @rs: the rs control structure
|
||||
* @rsc: the rs control structure
|
||||
* @data: data field of a given type
|
||||
* @par: received parity data field
|
||||
* @len: data length
|
||||
|
|
@ -319,9 +349,14 @@ EXPORT_SYMBOL_GPL(encode_rs8);
|
|||
* The syndrome and parity uses a uint16_t data type to enable
|
||||
* symbol size > 8. The calling code must take care of decoding of the
|
||||
* syndrome result and the received parity before calling this code.
|
||||
*
|
||||
* Note: The rs_control struct @rsc contains buffers which are used for
|
||||
* decoding, so the caller has to ensure that decoder invocations are
|
||||
* serialized.
|
||||
*
|
||||
* Returns the number of corrected bits or -EBADMSG for uncorrectable errors.
|
||||
*/
|
||||
int decode_rs8(struct rs_control *rs, uint8_t *data, uint16_t *par, int len,
|
||||
int decode_rs8(struct rs_control *rsc, uint8_t *data, uint16_t *par, int len,
|
||||
uint16_t *s, int no_eras, int *eras_pos, uint16_t invmsk,
|
||||
uint16_t *corr)
|
||||
{
|
||||
|
|
@ -333,7 +368,7 @@ EXPORT_SYMBOL_GPL(decode_rs8);
|
|||
#ifdef CONFIG_REED_SOLOMON_ENC16
|
||||
/**
|
||||
* encode_rs16 - Calculate the parity for data values (16bit data width)
|
||||
* @rs: the rs control structure
|
||||
* @rsc: the rs control structure
|
||||
* @data: data field of a given type
|
||||
* @len: data length
|
||||
* @par: parity data, must be initialized by caller (usually all 0)
|
||||
|
|
@ -341,7 +376,7 @@ EXPORT_SYMBOL_GPL(decode_rs8);
|
|||
*
|
||||
* Each field in the data array contains up to symbol size bits of valid data.
|
||||
*/
|
||||
int encode_rs16(struct rs_control *rs, uint16_t *data, int len, uint16_t *par,
|
||||
int encode_rs16(struct rs_control *rsc, uint16_t *data, int len, uint16_t *par,
|
||||
uint16_t invmsk)
|
||||
{
|
||||
#include "encode_rs.c"
|
||||
|
|
@ -352,7 +387,7 @@ EXPORT_SYMBOL_GPL(encode_rs16);
|
|||
#ifdef CONFIG_REED_SOLOMON_DEC16
|
||||
/**
|
||||
* decode_rs16 - Decode codeword (16bit data width)
|
||||
* @rs: the rs control structure
|
||||
* @rsc: the rs control structure
|
||||
* @data: data field of a given type
|
||||
* @par: received parity data field
|
||||
* @len: data length
|
||||
|
|
@ -363,9 +398,14 @@ EXPORT_SYMBOL_GPL(encode_rs16);
|
|||
* @corr: buffer to store correction bitmask on eras_pos
|
||||
*
|
||||
* Each field in the data array contains up to symbol size bits of valid data.
|
||||
*
|
||||
* Note: The rc_control struct @rsc contains buffers which are used for
|
||||
* decoding, so the caller has to ensure that decoder invocations are
|
||||
* serialized.
|
||||
*
|
||||
* Returns the number of corrected bits or -EBADMSG for uncorrectable errors.
|
||||
*/
|
||||
int decode_rs16(struct rs_control *rs, uint16_t *data, uint16_t *par, int len,
|
||||
int decode_rs16(struct rs_control *rsc, uint16_t *data, uint16_t *par, int len,
|
||||
uint16_t *s, int no_eras, int *eras_pos, uint16_t invmsk,
|
||||
uint16_t *corr)
|
||||
{
|
||||
|
|
@ -374,10 +414,6 @@ int decode_rs16(struct rs_control *rs, uint16_t *data, uint16_t *par, int len,
|
|||
EXPORT_SYMBOL_GPL(decode_rs16);
|
||||
#endif
|
||||
|
||||
EXPORT_SYMBOL_GPL(init_rs);
|
||||
EXPORT_SYMBOL_GPL(init_rs_non_canonical);
|
||||
EXPORT_SYMBOL_GPL(free_rs);
|
||||
|
||||
MODULE_LICENSE("GPL");
|
||||
MODULE_DESCRIPTION("Reed Solomon encoder/decoder");
|
||||
MODULE_AUTHOR("Phil Karn, Thomas Gleixner");
|
||||
|
|
|
|||
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