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path: root/drivers/crypto/nx/nx-842-crypto.c
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Diffstat (limited to 'drivers/crypto/nx/nx-842-crypto.c')
-rw-r--r--drivers/crypto/nx/nx-842-crypto.c580
1 files changed, 0 insertions, 580 deletions
diff --git a/drivers/crypto/nx/nx-842-crypto.c b/drivers/crypto/nx/nx-842-crypto.c
deleted file mode 100644
index d53a1dcd7..000000000
--- a/drivers/crypto/nx/nx-842-crypto.c
+++ /dev/null
@@ -1,580 +0,0 @@
-/*
- * Cryptographic API for the NX-842 hardware compression.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * Copyright (C) IBM Corporation, 2011-2015
- *
- * Original Authors: Robert Jennings <rcj@linux.vnet.ibm.com>
- * Seth Jennings <sjenning@linux.vnet.ibm.com>
- *
- * Rewrite: Dan Streetman <ddstreet@ieee.org>
- *
- * This is an interface to the NX-842 compression hardware in PowerPC
- * processors. Most of the complexity of this drvier is due to the fact that
- * the NX-842 compression hardware requires the input and output data buffers
- * to be specifically aligned, to be a specific multiple in length, and within
- * specific minimum and maximum lengths. Those restrictions, provided by the
- * nx-842 driver via nx842_constraints, mean this driver must use bounce
- * buffers and headers to correct misaligned in or out buffers, and to split
- * input buffers that are too large.
- *
- * This driver will fall back to software decompression if the hardware
- * decompression fails, so this driver's decompression should never fail as
- * long as the provided compressed buffer is valid. Any compressed buffer
- * created by this driver will have a header (except ones where the input
- * perfectly matches the constraints); so users of this driver cannot simply
- * pass a compressed buffer created by this driver over to the 842 software
- * decompression library. Instead, users must use this driver to decompress;
- * if the hardware fails or is unavailable, the compressed buffer will be
- * parsed and the header removed, and the raw 842 buffer(s) passed to the 842
- * software decompression library.
- *
- * This does not fall back to software compression, however, since the caller
- * of this function is specifically requesting hardware compression; if the
- * hardware compression fails, the caller can fall back to software
- * compression, and the raw 842 compressed buffer that the software compressor
- * creates can be passed to this driver for hardware decompression; any
- * buffer without our specific header magic is assumed to be a raw 842 buffer
- * and passed directly to the hardware. Note that the software compression
- * library will produce a compressed buffer that is incompatible with the
- * hardware decompressor if the original input buffer length is not a multiple
- * of 8; if such a compressed buffer is passed to this driver for
- * decompression, the hardware will reject it and this driver will then pass
- * it over to the software library for decompression.
- */
-
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include <linux/init.h>
-#include <linux/module.h>
-#include <linux/crypto.h>
-#include <linux/vmalloc.h>
-#include <linux/sw842.h>
-#include <linux/ratelimit.h>
-
-#include "nx-842.h"
-
-/* The first 5 bits of this magic are 0x1f, which is an invalid 842 5-bit
- * template (see lib/842/842.h), so this magic number will never appear at
- * the start of a raw 842 compressed buffer. That is important, as any buffer
- * passed to us without this magic is assumed to be a raw 842 compressed
- * buffer, and passed directly to the hardware to decompress.
- */
-#define NX842_CRYPTO_MAGIC (0xf842)
-#define NX842_CRYPTO_GROUP_MAX (0x20)
-#define NX842_CRYPTO_HEADER_SIZE(g) \
- (sizeof(struct nx842_crypto_header) + \
- sizeof(struct nx842_crypto_header_group) * (g))
-#define NX842_CRYPTO_HEADER_MAX_SIZE \
- NX842_CRYPTO_HEADER_SIZE(NX842_CRYPTO_GROUP_MAX)
-
-/* bounce buffer size */
-#define BOUNCE_BUFFER_ORDER (2)
-#define BOUNCE_BUFFER_SIZE \
- ((unsigned int)(PAGE_SIZE << BOUNCE_BUFFER_ORDER))
-
-/* try longer on comp because we can fallback to sw decomp if hw is busy */
-#define COMP_BUSY_TIMEOUT (250) /* ms */
-#define DECOMP_BUSY_TIMEOUT (50) /* ms */
-
-struct nx842_crypto_header_group {
- __be16 padding; /* unused bytes at start of group */
- __be32 compressed_length; /* compressed bytes in group */
- __be32 uncompressed_length; /* bytes after decompression */
-} __packed;
-
-struct nx842_crypto_header {
- __be16 magic; /* NX842_CRYPTO_MAGIC */
- __be16 ignore; /* decompressed end bytes to ignore */
- u8 groups; /* total groups in this header */
- struct nx842_crypto_header_group group[];
-} __packed;
-
-struct nx842_crypto_param {
- u8 *in;
- unsigned int iremain;
- u8 *out;
- unsigned int oremain;
- unsigned int ototal;
-};
-
-static int update_param(struct nx842_crypto_param *p,
- unsigned int slen, unsigned int dlen)
-{
- if (p->iremain < slen)
- return -EOVERFLOW;
- if (p->oremain < dlen)
- return -ENOSPC;
-
- p->in += slen;
- p->iremain -= slen;
- p->out += dlen;
- p->oremain -= dlen;
- p->ototal += dlen;
-
- return 0;
-}
-
-struct nx842_crypto_ctx {
- u8 *wmem;
- u8 *sbounce, *dbounce;
-
- struct nx842_crypto_header header;
- struct nx842_crypto_header_group group[NX842_CRYPTO_GROUP_MAX];
-};
-
-static int nx842_crypto_init(struct crypto_tfm *tfm)
-{
- struct nx842_crypto_ctx *ctx = crypto_tfm_ctx(tfm);
-
- ctx->wmem = kmalloc(nx842_workmem_size(), GFP_KERNEL);
- ctx->sbounce = (u8 *)__get_free_pages(GFP_KERNEL, BOUNCE_BUFFER_ORDER);
- ctx->dbounce = (u8 *)__get_free_pages(GFP_KERNEL, BOUNCE_BUFFER_ORDER);
- if (!ctx->wmem || !ctx->sbounce || !ctx->dbounce) {
- kfree(ctx->wmem);
- free_page((unsigned long)ctx->sbounce);
- free_page((unsigned long)ctx->dbounce);
- return -ENOMEM;
- }
-
- return 0;
-}
-
-static void nx842_crypto_exit(struct crypto_tfm *tfm)
-{
- struct nx842_crypto_ctx *ctx = crypto_tfm_ctx(tfm);
-
- kfree(ctx->wmem);
- free_page((unsigned long)ctx->sbounce);
- free_page((unsigned long)ctx->dbounce);
-}
-
-static int read_constraints(struct nx842_constraints *c)
-{
- int ret;
-
- ret = nx842_constraints(c);
- if (ret) {
- pr_err_ratelimited("could not get nx842 constraints : %d\n",
- ret);
- return ret;
- }
-
- /* limit maximum, to always have enough bounce buffer to decompress */
- if (c->maximum > BOUNCE_BUFFER_SIZE) {
- c->maximum = BOUNCE_BUFFER_SIZE;
- pr_info_once("limiting nx842 maximum to %x\n", c->maximum);
- }
-
- return 0;
-}
-
-static int nx842_crypto_add_header(struct nx842_crypto_header *hdr, u8 *buf)
-{
- int s = NX842_CRYPTO_HEADER_SIZE(hdr->groups);
-
- /* compress should have added space for header */
- if (s > be16_to_cpu(hdr->group[0].padding)) {
- pr_err("Internal error: no space for header\n");
- return -EINVAL;
- }
-
- memcpy(buf, hdr, s);
-
- print_hex_dump_debug("header ", DUMP_PREFIX_OFFSET, 16, 1, buf, s, 0);
-
- return 0;
-}
-
-static int compress(struct nx842_crypto_ctx *ctx,
- struct nx842_crypto_param *p,
- struct nx842_crypto_header_group *g,
- struct nx842_constraints *c,
- u16 *ignore,
- unsigned int hdrsize)
-{
- unsigned int slen = p->iremain, dlen = p->oremain, tmplen;
- unsigned int adj_slen = slen;
- u8 *src = p->in, *dst = p->out;
- int ret, dskip = 0;
- ktime_t timeout;
-
- if (p->iremain == 0)
- return -EOVERFLOW;
-
- if (p->oremain == 0 || hdrsize + c->minimum > dlen)
- return -ENOSPC;
-
- if (slen % c->multiple)
- adj_slen = round_up(slen, c->multiple);
- if (slen < c->minimum)
- adj_slen = c->minimum;
- if (slen > c->maximum)
- adj_slen = slen = c->maximum;
- if (adj_slen > slen || (u64)src % c->alignment) {
- adj_slen = min(adj_slen, BOUNCE_BUFFER_SIZE);
- slen = min(slen, BOUNCE_BUFFER_SIZE);
- if (adj_slen > slen)
- memset(ctx->sbounce + slen, 0, adj_slen - slen);
- memcpy(ctx->sbounce, src, slen);
- src = ctx->sbounce;
- slen = adj_slen;
- pr_debug("using comp sbounce buffer, len %x\n", slen);
- }
-
- dst += hdrsize;
- dlen -= hdrsize;
-
- if ((u64)dst % c->alignment) {
- dskip = (int)(PTR_ALIGN(dst, c->alignment) - dst);
- dst += dskip;
- dlen -= dskip;
- }
- if (dlen % c->multiple)
- dlen = round_down(dlen, c->multiple);
- if (dlen < c->minimum) {
-nospc:
- dst = ctx->dbounce;
- dlen = min(p->oremain, BOUNCE_BUFFER_SIZE);
- dlen = round_down(dlen, c->multiple);
- dskip = 0;
- pr_debug("using comp dbounce buffer, len %x\n", dlen);
- }
- if (dlen > c->maximum)
- dlen = c->maximum;
-
- tmplen = dlen;
- timeout = ktime_add_ms(ktime_get(), COMP_BUSY_TIMEOUT);
- do {
- dlen = tmplen; /* reset dlen, if we're retrying */
- ret = nx842_compress(src, slen, dst, &dlen, ctx->wmem);
- /* possibly we should reduce the slen here, instead of
- * retrying with the dbounce buffer?
- */
- if (ret == -ENOSPC && dst != ctx->dbounce)
- goto nospc;
- } while (ret == -EBUSY && ktime_before(ktime_get(), timeout));
- if (ret)
- return ret;
-
- dskip += hdrsize;
-
- if (dst == ctx->dbounce)
- memcpy(p->out + dskip, dst, dlen);
-
- g->padding = cpu_to_be16(dskip);
- g->compressed_length = cpu_to_be32(dlen);
- g->uncompressed_length = cpu_to_be32(slen);
-
- if (p->iremain < slen) {
- *ignore = slen - p->iremain;
- slen = p->iremain;
- }
-
- pr_debug("compress slen %x ignore %x dlen %x padding %x\n",
- slen, *ignore, dlen, dskip);
-
- return update_param(p, slen, dskip + dlen);
-}
-
-static int nx842_crypto_compress(struct crypto_tfm *tfm,
- const u8 *src, unsigned int slen,
- u8 *dst, unsigned int *dlen)
-{
- struct nx842_crypto_ctx *ctx = crypto_tfm_ctx(tfm);
- struct nx842_crypto_header *hdr = &ctx->header;
- struct nx842_crypto_param p;
- struct nx842_constraints c;
- unsigned int groups, hdrsize, h;
- int ret, n;
- bool add_header;
- u16 ignore = 0;
-
- p.in = (u8 *)src;
- p.iremain = slen;
- p.out = dst;
- p.oremain = *dlen;
- p.ototal = 0;
-
- *dlen = 0;
-
- ret = read_constraints(&c);
- if (ret)
- return ret;
-
- groups = min_t(unsigned int, NX842_CRYPTO_GROUP_MAX,
- DIV_ROUND_UP(p.iremain, c.maximum));
- hdrsize = NX842_CRYPTO_HEADER_SIZE(groups);
-
- /* skip adding header if the buffers meet all constraints */
- add_header = (p.iremain % c.multiple ||
- p.iremain < c.minimum ||
- p.iremain > c.maximum ||
- (u64)p.in % c.alignment ||
- p.oremain % c.multiple ||
- p.oremain < c.minimum ||
- p.oremain > c.maximum ||
- (u64)p.out % c.alignment);
-
- hdr->magic = cpu_to_be16(NX842_CRYPTO_MAGIC);
- hdr->groups = 0;
- hdr->ignore = 0;
-
- while (p.iremain > 0) {
- n = hdr->groups++;
- if (hdr->groups > NX842_CRYPTO_GROUP_MAX)
- return -ENOSPC;
-
- /* header goes before first group */
- h = !n && add_header ? hdrsize : 0;
-
- if (ignore)
- pr_warn("interal error, ignore is set %x\n", ignore);
-
- ret = compress(ctx, &p, &hdr->group[n], &c, &ignore, h);
- if (ret)
- return ret;
- }
-
- if (!add_header && hdr->groups > 1) {
- pr_err("Internal error: No header but multiple groups\n");
- return -EINVAL;
- }
-
- /* ignore indicates the input stream needed to be padded */
- hdr->ignore = cpu_to_be16(ignore);
- if (ignore)
- pr_debug("marked %d bytes as ignore\n", ignore);
-
- if (add_header)
- ret = nx842_crypto_add_header(hdr, dst);
- if (ret)
- return ret;
-
- *dlen = p.ototal;
-
- pr_debug("compress total slen %x dlen %x\n", slen, *dlen);
-
- return 0;
-}
-
-static int decompress(struct nx842_crypto_ctx *ctx,
- struct nx842_crypto_param *p,
- struct nx842_crypto_header_group *g,
- struct nx842_constraints *c,
- u16 ignore,
- bool usehw)
-{
- unsigned int slen = be32_to_cpu(g->compressed_length);
- unsigned int required_len = be32_to_cpu(g->uncompressed_length);
- unsigned int dlen = p->oremain, tmplen;
- unsigned int adj_slen = slen;
- u8 *src = p->in, *dst = p->out;
- u16 padding = be16_to_cpu(g->padding);
- int ret, spadding = 0, dpadding = 0;
- ktime_t timeout;
-
- if (!slen || !required_len)
- return -EINVAL;
-
- if (p->iremain <= 0 || padding + slen > p->iremain)
- return -EOVERFLOW;
-
- if (p->oremain <= 0 || required_len - ignore > p->oremain)
- return -ENOSPC;
-
- src += padding;
-
- if (!usehw)
- goto usesw;
-
- if (slen % c->multiple)
- adj_slen = round_up(slen, c->multiple);
- if (slen < c->minimum)
- adj_slen = c->minimum;
- if (slen > c->maximum)
- goto usesw;
- if (slen < adj_slen || (u64)src % c->alignment) {
- /* we can append padding bytes because the 842 format defines
- * an "end" template (see lib/842/842_decompress.c) and will
- * ignore any bytes following it.
- */
- if (slen < adj_slen)
- memset(ctx->sbounce + slen, 0, adj_slen - slen);
- memcpy(ctx->sbounce, src, slen);
- src = ctx->sbounce;
- spadding = adj_slen - slen;
- slen = adj_slen;
- pr_debug("using decomp sbounce buffer, len %x\n", slen);
- }
-
- if (dlen % c->multiple)
- dlen = round_down(dlen, c->multiple);
- if (dlen < required_len || (u64)dst % c->alignment) {
- dst = ctx->dbounce;
- dlen = min(required_len, BOUNCE_BUFFER_SIZE);
- pr_debug("using decomp dbounce buffer, len %x\n", dlen);
- }
- if (dlen < c->minimum)
- goto usesw;
- if (dlen > c->maximum)
- dlen = c->maximum;
-
- tmplen = dlen;
- timeout = ktime_add_ms(ktime_get(), DECOMP_BUSY_TIMEOUT);
- do {
- dlen = tmplen; /* reset dlen, if we're retrying */
- ret = nx842_decompress(src, slen, dst, &dlen, ctx->wmem);
- } while (ret == -EBUSY && ktime_before(ktime_get(), timeout));
- if (ret) {
-usesw:
- /* reset everything, sw doesn't have constraints */
- src = p->in + padding;
- slen = be32_to_cpu(g->compressed_length);
- spadding = 0;
- dst = p->out;
- dlen = p->oremain;
- dpadding = 0;
- if (dlen < required_len) { /* have ignore bytes */
- dst = ctx->dbounce;
- dlen = BOUNCE_BUFFER_SIZE;
- }
- pr_info_ratelimited("using software 842 decompression\n");
- ret = sw842_decompress(src, slen, dst, &dlen);
- }
- if (ret)
- return ret;
-
- slen -= spadding;
-
- dlen -= ignore;
- if (ignore)
- pr_debug("ignoring last %x bytes\n", ignore);
-
- if (dst == ctx->dbounce)
- memcpy(p->out, dst, dlen);
-
- pr_debug("decompress slen %x padding %x dlen %x ignore %x\n",
- slen, padding, dlen, ignore);
-
- return update_param(p, slen + padding, dlen);
-}
-
-static int nx842_crypto_decompress(struct crypto_tfm *tfm,
- const u8 *src, unsigned int slen,
- u8 *dst, unsigned int *dlen)
-{
- struct nx842_crypto_ctx *ctx = crypto_tfm_ctx(tfm);
- struct nx842_crypto_header *hdr;
- struct nx842_crypto_param p;
- struct nx842_constraints c;
- int n, ret, hdr_len;
- u16 ignore = 0;
- bool usehw = true;
-
- p.in = (u8 *)src;
- p.iremain = slen;
- p.out = dst;
- p.oremain = *dlen;
- p.ototal = 0;
-
- *dlen = 0;
-
- if (read_constraints(&c))
- usehw = false;
-
- hdr = (struct nx842_crypto_header *)src;
-
- /* If it doesn't start with our header magic number, assume it's a raw
- * 842 compressed buffer and pass it directly to the hardware driver
- */
- if (be16_to_cpu(hdr->magic) != NX842_CRYPTO_MAGIC) {
- struct nx842_crypto_header_group g = {
- .padding = 0,
- .compressed_length = cpu_to_be32(p.iremain),
- .uncompressed_length = cpu_to_be32(p.oremain),
- };
-
- ret = decompress(ctx, &p, &g, &c, 0, usehw);
- if (ret)
- return ret;
-
- *dlen = p.ototal;
-
- return 0;
- }
-
- if (!hdr->groups) {
- pr_err("header has no groups\n");
- return -EINVAL;
- }
- if (hdr->groups > NX842_CRYPTO_GROUP_MAX) {
- pr_err("header has too many groups %x, max %x\n",
- hdr->groups, NX842_CRYPTO_GROUP_MAX);
- return -EINVAL;
- }
-
- hdr_len = NX842_CRYPTO_HEADER_SIZE(hdr->groups);
- if (hdr_len > slen)
- return -EOVERFLOW;
-
- memcpy(&ctx->header, src, hdr_len);
- hdr = &ctx->header;
-
- for (n = 0; n < hdr->groups; n++) {
- /* ignore applies to last group */
- if (n + 1 == hdr->groups)
- ignore = be16_to_cpu(hdr->ignore);
-
- ret = decompress(ctx, &p, &hdr->group[n], &c, ignore, usehw);
- if (ret)
- return ret;
- }
-
- *dlen = p.ototal;
-
- pr_debug("decompress total slen %x dlen %x\n", slen, *dlen);
-
- return 0;
-}
-
-static struct crypto_alg alg = {
- .cra_name = "842",
- .cra_driver_name = "842-nx",
- .cra_priority = 300,
- .cra_flags = CRYPTO_ALG_TYPE_COMPRESS,
- .cra_ctxsize = sizeof(struct nx842_crypto_ctx),
- .cra_module = THIS_MODULE,
- .cra_init = nx842_crypto_init,
- .cra_exit = nx842_crypto_exit,
- .cra_u = { .compress = {
- .coa_compress = nx842_crypto_compress,
- .coa_decompress = nx842_crypto_decompress } }
-};
-
-static int __init nx842_crypto_mod_init(void)
-{
- return crypto_register_alg(&alg);
-}
-module_init(nx842_crypto_mod_init);
-
-static void __exit nx842_crypto_mod_exit(void)
-{
- crypto_unregister_alg(&alg);
-}
-module_exit(nx842_crypto_mod_exit);
-
-MODULE_LICENSE("GPL");
-MODULE_DESCRIPTION("IBM PowerPC Nest (NX) 842 Hardware Compression Interface");
-MODULE_ALIAS_CRYPTO("842");
-MODULE_ALIAS_CRYPTO("842-nx");
-MODULE_AUTHOR("Dan Streetman <ddstreet@ieee.org>");