diff options
Diffstat (limited to 'drivers/crypto/nx/nx-842-crypto.c')
| -rw-r--r-- | drivers/crypto/nx/nx-842-crypto.c | 580 |
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>"); |