linux/drivers/crypto/nx/nx-842.c
Thomas Gleixner c942fddf87 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157
Based on 3 normalized pattern(s):

  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

  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 [author] [kishon] [vijay] [abraham]
  [i] [kishon]@[ti] [com] 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

  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 [author] [graeme] [gregory]
  [gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i]
  [kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema]
  [hk] [hemahk]@[ti] [com] 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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1105 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:37 -07:00

522 lines
14 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Cryptographic API for the NX-842 hardware compression.
*
* Copyright (C) IBM Corporation, 2011-2015
*
* Designer of the Power data compression engine:
* Bulent Abali <abali@us.ibm.com>
*
* 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/vmalloc.h>
#include <linux/sw842.h>
#include <linux/spinlock.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_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_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;
}
int nx842_crypto_init(struct crypto_tfm *tfm, struct nx842_driver *driver)
{
struct nx842_crypto_ctx *ctx = crypto_tfm_ctx(tfm);
spin_lock_init(&ctx->lock);
ctx->driver = driver;
ctx->wmem = kmalloc(driver->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;
}
EXPORT_SYMBOL_GPL(nx842_crypto_init);
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);
}
EXPORT_SYMBOL_GPL(nx842_crypto_exit);
static void check_constraints(struct nx842_constraints *c)
{
/* limit maximum, to always have enough bounce buffer to decompress */
if (c->maximum > BOUNCE_BUFFER_SIZE)
c->maximum = BOUNCE_BUFFER_SIZE;
}
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 = ctx->driver->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);
}
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 = *ctx->driver->constraints;
unsigned int groups, hdrsize, h;
int ret, n;
bool add_header;
u16 ignore = 0;
check_constraints(&c);
p.in = (u8 *)src;
p.iremain = slen;
p.out = dst;
p.oremain = *dlen;
p.ototal = 0;
*dlen = 0;
groups = min_t(unsigned int, NX842_CRYPTO_GROUP_MAX,
DIV_ROUND_UP(p.iremain, c.maximum));
hdrsize = NX842_CRYPTO_HEADER_SIZE(groups);
spin_lock_bh(&ctx->lock);
/* 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++;
ret = -ENOSPC;
if (hdr->groups > NX842_CRYPTO_GROUP_MAX)
goto unlock;
/* header goes before first group */
h = !n && add_header ? hdrsize : 0;
if (ignore)
pr_warn("internal error, ignore is set %x\n", ignore);
ret = compress(ctx, &p, &hdr->group[n], &c, &ignore, h);
if (ret)
goto unlock;
}
if (!add_header && hdr->groups > 1) {
pr_err("Internal error: No header but multiple groups\n");
ret = -EINVAL;
goto unlock;
}
/* 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)
goto unlock;
*dlen = p.ototal;
pr_debug("compress total slen %x dlen %x\n", slen, *dlen);
unlock:
spin_unlock_bh(&ctx->lock);
return ret;
}
EXPORT_SYMBOL_GPL(nx842_crypto_compress);
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)
{
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;
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 (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 = ctx->driver->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;
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);
}
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 = *ctx->driver->constraints;
int n, ret, hdr_len;
u16 ignore = 0;
check_constraints(&c);
p.in = (u8 *)src;
p.iremain = slen;
p.out = dst;
p.oremain = *dlen;
p.ototal = 0;
*dlen = 0;
hdr = (struct nx842_crypto_header *)src;
spin_lock_bh(&ctx->lock);
/* 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);
if (ret)
goto unlock;
goto success;
}
if (!hdr->groups) {
pr_err("header has no groups\n");
ret = -EINVAL;
goto unlock;
}
if (hdr->groups > NX842_CRYPTO_GROUP_MAX) {
pr_err("header has too many groups %x, max %x\n",
hdr->groups, NX842_CRYPTO_GROUP_MAX);
ret = -EINVAL;
goto unlock;
}
hdr_len = NX842_CRYPTO_HEADER_SIZE(hdr->groups);
if (hdr_len > slen) {
ret = -EOVERFLOW;
goto unlock;
}
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);
if (ret)
goto unlock;
}
success:
*dlen = p.ototal;
pr_debug("decompress total slen %x dlen %x\n", slen, *dlen);
ret = 0;
unlock:
spin_unlock_bh(&ctx->lock);
return ret;
}
EXPORT_SYMBOL_GPL(nx842_crypto_decompress);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("IBM PowerPC Nest (NX) 842 Hardware Compression Driver");
MODULE_AUTHOR("Dan Streetman <ddstreet@ieee.org>");