original_kernel/fs/squashfs/lzo_wrapper.c

124 lines
2.5 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Squashfs - a compressed read only filesystem for Linux
*
* Copyright (c) 2010 LG Electronics
* Chan Jeong <chan.jeong@lge.com>
*
* lzo_wrapper.c
*/
#include <linux/mutex.h>
#include <linux/bio.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/lzo.h>
#include "squashfs_fs.h"
#include "squashfs_fs_sb.h"
#include "squashfs.h"
#include "decompressor.h"
#include "page_actor.h"
struct squashfs_lzo {
void *input;
void *output;
};
static void *lzo_init(struct squashfs_sb_info *msblk, void *buff)
{
int block_size = max_t(int, msblk->block_size, SQUASHFS_METADATA_SIZE);
struct squashfs_lzo *stream = kzalloc(sizeof(*stream), GFP_KERNEL);
if (stream == NULL)
goto failed;
stream->input = vmalloc(block_size);
if (stream->input == NULL)
goto failed;
stream->output = vmalloc(block_size);
if (stream->output == NULL)
goto failed2;
return stream;
failed2:
vfree(stream->input);
failed:
ERROR("Failed to allocate lzo workspace\n");
kfree(stream);
return ERR_PTR(-ENOMEM);
}
static void lzo_free(void *strm)
{
struct squashfs_lzo *stream = strm;
if (stream) {
vfree(stream->input);
vfree(stream->output);
}
kfree(stream);
}
static int lzo_uncompress(struct squashfs_sb_info *msblk, void *strm,
struct bio *bio, int offset, int length,
struct squashfs_page_actor *output)
{
struct bvec_iter_all iter_all = {};
struct bio_vec *bvec = bvec_init_iter_all(&iter_all);
struct squashfs_lzo *stream = strm;
void *buff = stream->input, *data;
int bytes = length, res;
size_t out_len = output->length;
while (bio_next_segment(bio, &iter_all)) {
int avail = min(bytes, ((int)bvec->bv_len) - offset);
data = bvec_virt(bvec);
memcpy(buff, data + offset, avail);
buff += avail;
bytes -= avail;
offset = 0;
}
res = lzo1x_decompress_safe(stream->input, (size_t)length,
stream->output, &out_len);
if (res != LZO_E_OK)
goto failed;
res = bytes = (int)out_len;
data = squashfs_first_page(output);
buff = stream->output;
while (data) {
if (bytes <= PAGE_SIZE) {
if (!IS_ERR(data))
memcpy(data, buff, bytes);
break;
} else {
if (!IS_ERR(data))
memcpy(data, buff, PAGE_SIZE);
buff += PAGE_SIZE;
bytes -= PAGE_SIZE;
data = squashfs_next_page(output);
}
}
squashfs_finish_page(output);
return res;
failed:
return -EIO;
}
const struct squashfs_decompressor squashfs_lzo_comp_ops = {
.init = lzo_init,
.free = lzo_free,
.decompress = lzo_uncompress,
.id = LZO_COMPRESSION,
.name = "lzo",
.alloc_buffer = 0,
.supported = 1
};