linux-imx

// SPDX-License-Identifier: GPL-2.0-or-later

/*

 * Cryptographic API for the 842 software compression algorithm.

 *

 * 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 the software implementation of compression and decompression using

 * the 842 format.  This uses the software 842 library at lib/842/ which is

 * only a reference implementation, and is very, very slow as compared to other

 * software compressors.  You probably do not want to use this software

 * compression.  If you have access to the PowerPC 842 compression hardware, you

 * want to use the 842 hardware compression interface, which is at:

 * drivers/crypto/nx/nx-842-crypto.c

 */

​

#include <linux/init.h>

#include <linux/module.h>

#include <linux/crypto.h>

#include <linux/sw842.h>

#include <crypto/internal/scompress.h>

​

struct crypto842_ctx {

    void *wmem; /* working memory for compress */

};

​

static void *crypto842_alloc_ctx(struct crypto_scomp *tfm)

{

    void *ctx;

​

    ctx = kmalloc(SW842_MEM_COMPRESS, GFP_KERNEL);

    if (!ctx)

        return ERR_PTR(-ENOMEM);

​

    return ctx;

}

​

static int crypto842_init(struct crypto_tfm *tfm)

{

    struct crypto842_ctx *ctx = crypto_tfm_ctx(tfm);

​

    ctx->wmem = crypto842_alloc_ctx(NULL);

    if (IS_ERR(ctx->wmem))

        return -ENOMEM;

​

    return 0;

}

​

static void crypto842_free_ctx(struct crypto_scomp *tfm, void *ctx)

{

    kfree(ctx);

}

​

static void crypto842_exit(struct crypto_tfm *tfm)

{

    struct crypto842_ctx *ctx = crypto_tfm_ctx(tfm);

​

    crypto842_free_ctx(NULL, ctx->wmem);

}