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authorLinus Torvalds <torvalds@linux-foundation.org>2018-06-05 10:48:05 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2018-06-05 10:48:05 -0700
commit25d80be86c5d7f53df41ec5ce96f6c6543cac245 (patch)
treea18fe8d5281d0ed44c049d5a59da499278bb6e3e
parenta74e0c4c9cb02d44bc5ec1a70a6ba599366fb130 (diff)
parent45888b40d2a6221d46bb69959e2600ddba71cc1f (diff)
downloadlinux-0-day-25d80be86c5d7f53df41ec5ce96f6c6543cac245.tar.gz
linux-0-day-25d80be86c5d7f53df41ec5ce96f6c6543cac245.tar.xz
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
-rw-r--r--drivers/md/dm-verity-fec.c2
-rw-r--r--drivers/mtd/nand/raw/cafe_nand.c7
-rw-r--r--drivers/mtd/nand/raw/diskonchip.c67
-rw-r--r--include/linux/rslib.h74
-rw-r--r--lib/reed_solomon/decode_rs.c34
-rw-r--r--lib/reed_solomon/encode_rs.c15
-rw-r--r--lib/reed_solomon/reed_solomon.c240
7 files changed, 243 insertions, 196 deletions
diff --git a/drivers/md/dm-verity-fec.c b/drivers/md/dm-verity-fec.c
index 86405869f1af..684af08d0747 100644
--- a/drivers/md/dm-verity-fec.c
+++ b/drivers/md/dm-verity-fec.c
@@ -570,7 +570,7 @@ static void *fec_rs_alloc(gfp_t gfp_mask, void *pool_data)
{
struct dm_verity *v = (struct dm_verity *)pool_data;
- return init_rs(8, 0x11d, 0, 1, v->fec->roots);
+ return init_rs_gfp(8, 0x11d, 0, 1, v->fec->roots, gfp_mask);
}
static void fec_rs_free(void *element, void *pool_data)
diff --git a/drivers/mtd/nand/raw/cafe_nand.c b/drivers/mtd/nand/raw/cafe_nand.c
index d8c8c9d1e640..d721f489b38b 100644
--- a/drivers/mtd/nand/raw/cafe_nand.c
+++ b/drivers/mtd/nand/raw/cafe_nand.c
@@ -394,12 +394,13 @@ static int cafe_nand_read_page(struct mtd_info *mtd, struct nand_chip *chip,
for (i=0; i<8; i+=2) {
uint32_t tmp = cafe_readl(cafe, NAND_ECC_SYN01 + (i*2));
- syn[i] = cafe->rs->index_of[tmp & 0xfff];
- syn[i+1] = cafe->rs->index_of[(tmp >> 16) & 0xfff];
+
+ syn[i] = cafe->rs->codec->index_of[tmp & 0xfff];
+ syn[i+1] = cafe->rs->codec->index_of[(tmp >> 16) & 0xfff];
}
n = decode_rs16(cafe->rs, NULL, NULL, 1367, syn, 0, pos, 0,
- pat);
+ pat);
for (i = 0; i < n; i++) {
int p = pos[i];
diff --git a/drivers/mtd/nand/raw/diskonchip.c b/drivers/mtd/nand/raw/diskonchip.c
index 86a258de0b75..2b7b2b982b77 100644
--- a/drivers/mtd/nand/raw/diskonchip.c
+++ b/drivers/mtd/nand/raw/diskonchip.c
@@ -66,6 +66,7 @@ struct doc_priv {
int curchip;
int mh0_page;
int mh1_page;
+ struct rs_control *rs_decoder;
struct mtd_info *nextdoc;
/* Handle the last stage of initialization (BBT scan, partitioning) */
@@ -123,9 +124,6 @@ MODULE_PARM_DESC(doc_config_location, "Physical memory address at which to probe
/* Number of symbols */
#define NN 1023
-/* the Reed Solomon control structure */
-static struct rs_control *rs_decoder;
-
/*
* The HW decoder in the DoC ASIC's provides us a error syndrome,
* which we must convert to a standard syndrome usable by the generic
@@ -140,6 +138,7 @@ static int doc_ecc_decode(struct rs_control *rs, uint8_t *data, uint8_t *ecc)
int i, j, nerr, errpos[8];
uint8_t parity;
uint16_t ds[4], s[5], tmp, errval[8], syn[4];
+ struct rs_codec *cd = rs->codec;
memset(syn, 0, sizeof(syn));
/* Convert the ecc bytes into words */
@@ -160,15 +159,15 @@ static int doc_ecc_decode(struct rs_control *rs, uint8_t *data, uint8_t *ecc)
for (j = 1; j < NROOTS; j++) {
if (ds[j] == 0)
continue;
- tmp = rs->index_of[ds[j]];
+ tmp = cd->index_of[ds[j]];
for (i = 0; i < NROOTS; i++)
- s[i] ^= rs->alpha_to[rs_modnn(rs, tmp + (FCR + i) * j)];
+ s[i] ^= cd->alpha_to[rs_modnn(cd, tmp + (FCR + i) * j)];
}
/* Calc syn[i] = s[i] / alpha^(v + i) */
for (i = 0; i < NROOTS; i++) {
if (s[i])
- syn[i] = rs_modnn(rs, rs->index_of[s[i]] + (NN - FCR - i));
+ syn[i] = rs_modnn(cd, cd->index_of[s[i]] + (NN - FCR - i));
}
/* Call the decoder library */
nerr = decode_rs16(rs, NULL, NULL, 1019, syn, 0, errpos, 0, errval);
@@ -930,7 +929,7 @@ static int doc200x_correct_data(struct mtd_info *mtd, u_char *dat,
calc_ecc[i] = ReadDOC_(docptr, DoC_ECCSyndrome0 + i);
}
- ret = doc_ecc_decode(rs_decoder, dat, calc_ecc);
+ ret = doc_ecc_decode(doc->rs_decoder, dat, calc_ecc);
if (ret > 0)
pr_err("doc200x_correct_data corrected %d errors\n",
ret);
@@ -1421,10 +1420,10 @@ static inline int __init doc2001plus_init(struct mtd_info *mtd)
static int __init doc_probe(unsigned long physadr)
{
+ struct nand_chip *nand = NULL;
+ struct doc_priv *doc = NULL;
unsigned char ChipID;
struct mtd_info *mtd;
- struct nand_chip *nand;
- struct doc_priv *doc;
void __iomem *virtadr;
unsigned char save_control;
unsigned char tmp, tmpb, tmpc;
@@ -1561,8 +1560,25 @@ static int __init doc_probe(unsigned long physadr)
goto fail;
}
+
+ /*
+ * Allocate a RS codec instance
+ *
+ * Symbolsize is 10 (bits)
+ * Primitve polynomial is x^10+x^3+1
+ * First consecutive root is 510
+ * Primitve element to generate roots = 1
+ * Generator polinomial degree = 4
+ */
+ doc = (struct doc_priv *) (nand + 1);
+ doc->rs_decoder = init_rs(10, 0x409, FCR, 1, NROOTS);
+ if (!doc->rs_decoder) {
+ pr_err("DiskOnChip: Could not create a RS codec\n");
+ ret = -ENOMEM;
+ goto fail;
+ }
+
mtd = nand_to_mtd(nand);
- doc = (struct doc_priv *) (nand + 1);
nand->bbt_td = (struct nand_bbt_descr *) (doc + 1);
nand->bbt_md = nand->bbt_td + 1;
@@ -1612,7 +1628,6 @@ static int __init doc_probe(unsigned long physadr)
haven't yet added it. This is handled without incident by
mtd_device_unregister, as far as I can tell. */
nand_release(mtd);
- kfree(nand);
goto fail;
}
@@ -1625,6 +1640,9 @@ static int __init doc_probe(unsigned long physadr)
actually a DiskOnChip. */
WriteDOC(save_control, virtadr, DOCControl);
fail:
+ if (doc)
+ free_rs(doc->rs_decoder);
+ kfree(nand);
iounmap(virtadr);
error_ioremap:
@@ -1647,6 +1665,7 @@ static void release_nanddoc(void)
nand_release(mtd);
iounmap(doc->virtadr);
release_mem_region(doc->physadr, DOC_IOREMAP_LEN);
+ free_rs(doc->rs_decoder);
kfree(nand);
}
}
@@ -1655,27 +1674,12 @@ static int __init init_nanddoc(void)
{
int i, ret = 0;
- /* We could create the decoder on demand, if memory is a concern.
- * This way we have it handy, if an error happens
- *
- * Symbolsize is 10 (bits)
- * Primitve polynomial is x^10+x^3+1
- * first consecutive root is 510
- * primitve element to generate roots = 1
- * generator polinomial degree = 4
- */
- rs_decoder = init_rs(10, 0x409, FCR, 1, NROOTS);
- if (!rs_decoder) {
- pr_err("DiskOnChip: Could not create a RS decoder\n");
- return -ENOMEM;
- }
-
if (doc_config_location) {
pr_info("Using configured DiskOnChip probe address 0x%lx\n",
doc_config_location);
ret = doc_probe(doc_config_location);
if (ret < 0)
- goto outerr;
+ return ret;
} else {
for (i = 0; (doc_locations[i] != 0xffffffff); i++) {
doc_probe(doc_locations[i]);
@@ -1686,11 +1690,7 @@ static int __init init_nanddoc(void)
if (!doclist) {
pr_info("No valid DiskOnChip devices found\n");
ret = -ENODEV;
- goto outerr;
}
- return 0;
- outerr:
- free_rs(rs_decoder);
return ret;
}
@@ -1698,11 +1698,6 @@ static void __exit cleanup_nanddoc(void)
{
/* Cleanup the nand/DoC resources */
release_nanddoc();
-
- /* Free the reed solomon resources */
- if (rs_decoder) {
- free_rs(rs_decoder);
- }
}
module_init(init_nanddoc);
diff --git a/include/linux/rslib.h b/include/linux/rslib.h
index 746580c1939c..5974cedd008c 100644
--- a/include/linux/rslib.h
+++ b/include/linux/rslib.h
@@ -1,28 +1,21 @@
+// SPDX-License-Identifier: GPL-2.0
/*
- * include/linux/rslib.h
- *
- * Overview:
- * Generic Reed Solomon encoder / decoder library
+ * Generic Reed Solomon encoder / decoder library
*
* Copyright (C) 2004 Thomas Gleixner (tglx@linutronix.de)
*
* RS code lifted from reed solomon library written by Phil Karn
* Copyright 2002 Phil Karn, KA9Q
- *
- * $Id: rslib.h,v 1.4 2005/11/07 11:14:52 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.
*/
-
#ifndef _RSLIB_H_
#define _RSLIB_H_
#include <linux/list.h>
+#include <linux/types.h> /* for gfp_t */
+#include <linux/gfp.h> /* for GFP_KERNEL */
/**
- * struct rs_control - rs control structure
+ * struct rs_codec - rs codec data
*
* @mm: Bits per symbol
* @nn: Symbols per block (= (1<<mm)-1)
@@ -36,24 +29,34 @@
* @gfpoly: The primitive generator polynominal
* @gffunc: Function to generate the field, if non-canonical representation
* @users: Users of this structure
- * @list: List entry for the rs control list
+ * @list: List entry for the rs codec list
*/
-struct rs_control {
- int mm;
- int nn;
+struct rs_codec {
+ int mm;
+ int nn;
uint16_t *alpha_to;
uint16_t *index_of;
uint16_t *genpoly;
- int nroots;
- int fcr;
- int prim;
- int iprim;
+ int nroots;
+ int fcr;
+ int prim;
+ int iprim;
int gfpoly;
int (*gffunc)(int);
int users;
struct list_head list;
};
+/**
+ * struct rs_control - rs control structure per instance
+ * @codec: The codec used for this instance
+ * @buffers: Internal scratch buffers used in calls to decode_rs()
+ */
+struct rs_control {
+ struct rs_codec *codec;
+ uint16_t buffers[0];
+};
+
/* General purpose RS codec, 8-bit data width, symbol width 1-15 bit */
#ifdef CONFIG_REED_SOLOMON_ENC8
int encode_rs8(struct rs_control *rs, uint8_t *data, int len, uint16_t *par,
@@ -76,18 +79,37 @@ int decode_rs16(struct rs_control *rs, uint16_t *data, uint16_t *par, int len,
uint16_t *corr);
#endif
-/* Create or get a matching rs control structure */
-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);
+
+/**
+ * init_rs - 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
+ * in index form
+ * @prim: primitive element to generate polynomial roots
+ * @nroots: RS code generator polynomial degree (number of roots)
+ *
+ * Allocations use GFP_KERNEL.
+ */
+static inline struct rs_control *init_rs(int symsize, int gfpoly, int fcr,
+ 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;
diff --git a/lib/reed_solomon/decode_rs.c b/lib/reed_solomon/decode_rs.c
index 0ec3f257ffdf..1db74eb098d0 100644
--- a/lib/reed_solomon/decode_rs.c
+++ b/lib/reed_solomon/decode_rs.c
@@ -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);
diff --git a/lib/reed_solomon/encode_rs.c b/lib/reed_solomon/encode_rs.c
index 0b5b1a6728ec..9112d46e869e 100644
--- a/lib/reed_solomon/encode_rs.c
+++ b/lib/reed_solomon/encode_rs.c
@@ -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;
diff --git a/lib/reed_solomon/reed_solomon.c b/lib/reed_solomon/reed_solomon.c
index 06d04cfa9339..dfcf54242fb9 100644
--- a/lib/reed_solomon/reed_solomon.c
+++ b/lib/reed_solomon/reed_solomon.c
@@ -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");