linux/drivers/crypto/nx/nx-842.c
Dan Streetman 2c6f6eabc0 crypto: nx - replace NX842_MEM_COMPRESS with function
Replace the NX842_MEM_COMPRESS define with a function that returns the
specific platform driver's required working memory size.

The common nx-842.c driver refuses to load if there is no platform
driver present, so instead of defining an approximate working memory
size that's the maximum approximate size of both platform driver's
size requirements, the platform driver can directly provide its
specific, i.e. sizeof(struct nx842_workmem), size requirements which
the 842-nx crypto compression driver will use.

This saves memory by both reducing the required size of each driver
to the specific sizeof() amount, as well as using the specific loaded
platform driver's required amount, instead of the maximum of both.

Signed-off-by: Dan Streetman <ddstreet@ieee.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-06-15 18:15:57 +08:00

104 lines
3.2 KiB
C

/*
* Driver frontend for IBM Power 842 compression accelerator
*
* Copyright (C) 2015 Dan Streetman, IBM Corp
*
* Designer of the Power data compression engine:
* Bulent Abali <abali@us.ibm.com>
*
* 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.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include "nx-842.h"
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Dan Streetman <ddstreet@ieee.org>");
MODULE_DESCRIPTION("842 H/W Compression driver for IBM Power processors");
/**
* nx842_constraints
*
* This provides the driver's constraints. Different nx842 implementations
* may have varying requirements. The constraints are:
* @alignment: All buffers should be aligned to this
* @multiple: All buffer lengths should be a multiple of this
* @minimum: Buffer lengths must not be less than this amount
* @maximum: Buffer lengths must not be more than this amount
*
* The constraints apply to all buffers and lengths, both input and output,
* for both compression and decompression, except for the minimum which
* only applies to compression input and decompression output; the
* compressed data can be less than the minimum constraint. It can be
* assumed that compressed data will always adhere to the multiple
* constraint.
*
* The driver may succeed even if these constraints are violated;
* however the driver can return failure or suffer reduced performance
* if any constraint is not met.
*/
int nx842_constraints(struct nx842_constraints *c)
{
memcpy(c, nx842_platform_driver()->constraints, sizeof(*c));
return 0;
}
EXPORT_SYMBOL_GPL(nx842_constraints);
/**
* nx842_workmem_size
*
* Get the amount of working memory the driver requires.
*/
size_t nx842_workmem_size(void)
{
return nx842_platform_driver()->workmem_size;
}
EXPORT_SYMBOL_GPL(nx842_workmem_size);
int nx842_compress(const unsigned char *in, unsigned int ilen,
unsigned char *out, unsigned int *olen, void *wmem)
{
return nx842_platform_driver()->compress(in, ilen, out, olen, wmem);
}
EXPORT_SYMBOL_GPL(nx842_compress);
int nx842_decompress(const unsigned char *in, unsigned int ilen,
unsigned char *out, unsigned int *olen, void *wmem)
{
return nx842_platform_driver()->decompress(in, ilen, out, olen, wmem);
}
EXPORT_SYMBOL_GPL(nx842_decompress);
static __init int nx842_init(void)
{
request_module("nx-compress-powernv");
request_module("nx-compress-pseries");
/* we prevent loading if there's no platform driver, and we get the
* module that set it so it won't unload, so we don't need to check
* if it's set in any of the above functions
*/
if (!nx842_platform_driver_get()) {
pr_err("no nx842 driver found.\n");
return -ENODEV;
}
return 0;
}
module_init(nx842_init);
static void __exit nx842_exit(void)
{
nx842_platform_driver_put();
}
module_exit(nx842_exit);