124 lines · c
1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Squashfs - a compressed read only filesystem for Linux4 *5 * Copyright (c) 2010 LG Electronics6 * Chan Jeong <chan.jeong@lge.com>7 *8 * lzo_wrapper.c9 */10 11#include <linux/mutex.h>12#include <linux/bio.h>13#include <linux/slab.h>14#include <linux/vmalloc.h>15#include <linux/lzo.h>16 17#include "squashfs_fs.h"18#include "squashfs_fs_sb.h"19#include "squashfs.h"20#include "decompressor.h"21#include "page_actor.h"22 23struct squashfs_lzo {24 void *input;25 void *output;26};27 28static void *lzo_init(struct squashfs_sb_info *msblk, void *buff)29{30 int block_size = max_t(int, msblk->block_size, SQUASHFS_METADATA_SIZE);31 32 struct squashfs_lzo *stream = kzalloc(sizeof(*stream), GFP_KERNEL);33 if (stream == NULL)34 goto failed;35 stream->input = vmalloc(block_size);36 if (stream->input == NULL)37 goto failed;38 stream->output = vmalloc(block_size);39 if (stream->output == NULL)40 goto failed2;41 42 return stream;43 44failed2:45 vfree(stream->input);46failed:47 ERROR("Failed to allocate lzo workspace\n");48 kfree(stream);49 return ERR_PTR(-ENOMEM);50}51 52 53static void lzo_free(void *strm)54{55 struct squashfs_lzo *stream = strm;56 57 if (stream) {58 vfree(stream->input);59 vfree(stream->output);60 }61 kfree(stream);62}63 64 65static int lzo_uncompress(struct squashfs_sb_info *msblk, void *strm,66 struct bio *bio, int offset, int length,67 struct squashfs_page_actor *output)68{69 struct bvec_iter_all iter_all = {};70 struct bio_vec *bvec = bvec_init_iter_all(&iter_all);71 struct squashfs_lzo *stream = strm;72 void *buff = stream->input, *data;73 int bytes = length, res;74 size_t out_len = output->length;75 76 while (bio_next_segment(bio, &iter_all)) {77 int avail = min(bytes, ((int)bvec->bv_len) - offset);78 79 data = bvec_virt(bvec);80 memcpy(buff, data + offset, avail);81 buff += avail;82 bytes -= avail;83 offset = 0;84 }85 86 res = lzo1x_decompress_safe(stream->input, (size_t)length,87 stream->output, &out_len);88 if (res != LZO_E_OK)89 goto failed;90 91 res = bytes = (int)out_len;92 data = squashfs_first_page(output);93 buff = stream->output;94 while (data) {95 if (bytes <= PAGE_SIZE) {96 if (!IS_ERR(data))97 memcpy(data, buff, bytes);98 break;99 } else {100 if (!IS_ERR(data))101 memcpy(data, buff, PAGE_SIZE);102 buff += PAGE_SIZE;103 bytes -= PAGE_SIZE;104 data = squashfs_next_page(output);105 }106 }107 squashfs_finish_page(output);108 109 return res;110 111failed:112 return -EIO;113}114 115const struct squashfs_decompressor squashfs_lzo_comp_ops = {116 .init = lzo_init,117 .free = lzo_free,118 .decompress = lzo_uncompress,119 .id = LZO_COMPRESSION,120 .name = "lzo",121 .alloc_buffer = 0,122 .supported = 1123};124