[linux-2.6-block.git] / fs / squashfs / decompressor_single.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2013
 * Phillip Lougher <phillip@squashfs.org.uk>
 */

#include <linux/types.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <linux/bio.h>

#include "squashfs_fs.h"
#include "squashfs_fs_sb.h"
#include "decompressor.h"
#include "squashfs.h"

/*
 * This file implements single-threaded decompression in the
 * decompressor framework
 */

struct squashfs_stream {
	void		*stream;
	struct mutex	mutex;
};

static void *squashfs_decompressor_create(struct squashfs_sb_info *msblk,
						void *comp_opts)
{
	struct squashfs_stream *stream;
	int err = -ENOMEM;

	stream = kmalloc(sizeof(*stream), GFP_KERNEL);
	if (stream == NULL)
		goto out;

	stream->stream = msblk->decompressor->init(msblk, comp_opts);
	if (IS_ERR(stream->stream)) {
		err = PTR_ERR(stream->stream);
		goto out;
	}

	kfree(comp_opts);
	mutex_init(&stream->mutex);
	return stream;

out:
	kfree(stream);
	return ERR_PTR(err);
}

static void squashfs_decompressor_destroy(struct squashfs_sb_info *msblk)
{
	struct squashfs_stream *stream = msblk->stream;

	if (stream) {
		msblk->decompressor->free(stream->stream);
		kfree(stream);
	}
}

static int squashfs_decompress(struct squashfs_sb_info *msblk, struct bio *bio,
			int offset, int length,
			struct squashfs_page_actor *output)
{
	int res;
	struct squashfs_stream *stream = msblk->stream;

	mutex_lock(&stream->mutex);
	res = msblk->decompressor->decompress(msblk, stream->stream, bio,
		offset, length, output);
	mutex_unlock(&stream->mutex);

	if (res < 0)
		ERROR("%s decompression failed, data probably corrupt\n",
			msblk->decompressor->name);

	return res;
}

static int squashfs_max_decompressors(void)
{
	return 1;
}

const struct squashfs_decompressor_thread_ops squashfs_decompressor_single = {
	.create = squashfs_decompressor_create,
	.destroy = squashfs_decompressor_destroy,
	.decompress = squashfs_decompress,
	.max_decompressors = squashfs_max_decompressors,
};
Commit	Line	Data
20c8ccb1	1	// SPDX-License-Identifier: GPL-2.0-only
9508c6b9 PL	2	/*
	3	* Copyright (c) 2013
	4	* Phillip Lougher <phillip@squashfs.org.uk>
9508c6b9 PL	5	*/
	6
	7	#include <linux/types.h>
	8	#include <linux/mutex.h>
	9	#include <linux/slab.h>
93e72b3c	10	#include <linux/bio.h>
9508c6b9 PL	11
	12	#include "squashfs_fs.h"
	13	#include "squashfs_fs_sb.h"
	14	#include "decompressor.h"
	15	#include "squashfs.h"
	16
	17	/*
	18	* This file implements single-threaded decompression in the
	19	* decompressor framework
	20	*/
	21
	22	struct squashfs_stream {
	23	void *stream;
	24	struct mutex mutex;
	25	};
	26
80f78409	27	static void squashfs_decompressor_create(struct squashfs_sb_info msblk,
9508c6b9 PL	28	void *comp_opts)
	29	{
	30	struct squashfs_stream *stream;
	31	int err = -ENOMEM;
	32
	33	stream = kmalloc(sizeof(*stream), GFP_KERNEL);
	34	if (stream == NULL)
	35	goto out;
	36
	37	stream->stream = msblk->decompressor->init(msblk, comp_opts);
	38	if (IS_ERR(stream->stream)) {
	39	err = PTR_ERR(stream->stream);
	40	goto out;
	41	}
	42
	43	kfree(comp_opts);
	44	mutex_init(&stream->mutex);
	45	return stream;
	46
	47	out:
	48	kfree(stream);
	49	return ERR_PTR(err);
	50	}
	51
80f78409	52	static void squashfs_decompressor_destroy(struct squashfs_sb_info *msblk)
9508c6b9 PL	53	{
	54	struct squashfs_stream *stream = msblk->stream;
	55
	56	if (stream) {
	57	msblk->decompressor->free(stream->stream);
	58	kfree(stream);
	59	}
	60	}
	61
80f78409	62	static int squashfs_decompress(struct squashfs_sb_info msblk, struct bio bio,
93e72b3c PL	63	int offset, int length,
93e72b3c PL	64	struct squashfs_page_actor *output)
9508c6b9 PL	65	{
	66	int res;
	67	struct squashfs_stream *stream = msblk->stream;
	68
	69	mutex_lock(&stream->mutex);
93e72b3c	70	res = msblk->decompressor->decompress(msblk, stream->stream, bio,
846b730e	71	offset, length, output);
9508c6b9 PL	72	mutex_unlock(&stream->mutex);
	73
	74	if (res < 0)
	75	ERROR("%s decompression failed, data probably corrupt\n",
	76	msblk->decompressor->name);
	77
	78	return res;
	79	}
	80
80f78409	81	static int squashfs_max_decompressors(void)
9508c6b9 PL	82	{
	83	return 1;
	84	}
80f78409 XN	85
	86	const struct squashfs_decompressor_thread_ops squashfs_decompressor_single = {
	87	.create = squashfs_decompressor_create,
	88	.destroy = squashfs_decompressor_destroy,
	89	.decompress = squashfs_decompress,
	90	.max_decompressors = squashfs_max_decompressors,
	91	};