/* * Squashfs - a compressed read only filesystem for Linux * * Copyright (c) 2010 LG Electronics * Chan Jeong <chan.jeong@lge.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, * 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. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. * * lzo_wrapper.c */ #include <linux/mutex.h> #include <linux/buffer_head.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 buffer_head **bh, int b, int offset, int length, struct squashfs_page_actor *output) { struct squashfs_lzo *stream = strm; void *buff = stream->input, *data; int avail, i, bytes = length, res; size_t out_len = output->length; for (i = 0; i < b; i++) { avail = min(bytes, msblk->devblksize - offset); memcpy(buff, bh[i]->b_data + offset, avail); buff += avail; bytes -= avail; offset = 0; put_bh(bh[i]); } 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_CACHE_SIZE) { memcpy(data, buff, bytes); break; } else { memcpy(data, buff, PAGE_CACHE_SIZE); buff += PAGE_CACHE_SIZE; bytes -= PAGE_CACHE_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", .supported = 1 };