diff options
| -rw-r--r-- | fs/squashfs/squashfs_fs.h | 1 | ||||
| -rw-r--r-- | fs/squashfs/xz_wrapper.c | 153 |
2 files changed, 154 insertions, 0 deletions
diff --git a/fs/squashfs/squashfs_fs.h b/fs/squashfs/squashfs_fs.h index c5137fc9ab1..39533feffd6 100644 --- a/fs/squashfs/squashfs_fs.h +++ b/fs/squashfs/squashfs_fs.h @@ -238,6 +238,7 @@ struct meta_index { #define ZLIB_COMPRESSION 1 #define LZMA_COMPRESSION 2 #define LZO_COMPRESSION 3 +#define XZ_COMPRESSION 4 struct squashfs_super_block { __le32 s_magic; diff --git a/fs/squashfs/xz_wrapper.c b/fs/squashfs/xz_wrapper.c new file mode 100644 index 00000000000..856756ca5ee --- /dev/null +++ b/fs/squashfs/xz_wrapper.c @@ -0,0 +1,153 @@ +/* + * Squashfs - a compressed read only filesystem for Linux + * + * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 + * Phillip Lougher <phillip@lougher.demon.co.uk> + * + * 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. + * + * xz_wrapper.c + */ + + +#include <linux/mutex.h> +#include <linux/buffer_head.h> +#include <linux/slab.h> +#include <linux/xz.h> + +#include "squashfs_fs.h" +#include "squashfs_fs_sb.h" +#include "squashfs_fs_i.h" +#include "squashfs.h" +#include "decompressor.h" + +struct squashfs_xz { + struct xz_dec *state; + struct xz_buf buf; +}; + +static void *squashfs_xz_init(struct squashfs_sb_info *msblk) +{ + int block_size = max_t(int, msblk->block_size, SQUASHFS_METADATA_SIZE); + + struct squashfs_xz *stream = kmalloc(sizeof(*stream), GFP_KERNEL); + if (stream == NULL) + goto failed; + + stream->state = xz_dec_init(XZ_PREALLOC, block_size); + if (stream->state == NULL) + goto failed; + + return stream; + +failed: + ERROR("Failed to allocate xz workspace\n"); + kfree(stream); + return NULL; +} + + +static void squashfs_xz_free(void *strm) +{ + struct squashfs_xz *stream = strm; + + if (stream) { + xz_dec_end(stream->state); + kfree(stream); + } +} + + +static int squashfs_xz_uncompress(struct squashfs_sb_info *msblk, void **buffer, + struct buffer_head **bh, int b, int offset, int length, int srclength, + int pages) +{ + enum xz_ret xz_err; + int avail, total = 0, k = 0, page = 0; + struct squashfs_xz *stream = msblk->stream; + + mutex_lock(&msblk->read_data_mutex); + + xz_dec_reset(stream->state); + stream->buf.in_pos = 0; + stream->buf.in_size = 0; + stream->buf.out_pos = 0; + stream->buf.out_size = PAGE_CACHE_SIZE; + stream->buf.out = buffer[page++]; + + do { + if (stream->buf.in_pos == stream->buf.in_size && k < b) { + avail = min(length, msblk->devblksize - offset); + length -= avail; + wait_on_buffer(bh[k]); + if (!buffer_uptodate(bh[k])) + goto release_mutex; + + if (avail == 0) { + offset = 0; + put_bh(bh[k++]); + continue; + } + + stream->buf.in = bh[k]->b_data + offset; + stream->buf.in_size = avail; + stream->buf.in_pos = 0; + offset = 0; + } + + if (stream->buf.out_pos == stream->buf.out_size + && page < pages) { + stream->buf.out = buffer[page++]; + stream->buf.out_pos = 0; + total += PAGE_CACHE_SIZE; + } + + xz_err = xz_dec_run(stream->state, &stream->buf); + + if (stream->buf.in_pos == stream->buf.in_size && k < b) + put_bh(bh[k++]); + } while (xz_err == XZ_OK); + + if (xz_err != XZ_STREAM_END) { + ERROR("xz_dec_run error, data probably corrupt\n"); + goto release_mutex; + } + + if (k < b) { + ERROR("xz_uncompress error, input remaining\n"); + goto release_mutex; + } + + total += stream->buf.out_pos; + mutex_unlock(&msblk->read_data_mutex); + return total; + +release_mutex: + mutex_unlock(&msblk->read_data_mutex); + + for (; k < b; k++) + put_bh(bh[k]); + + return -EIO; +} + +const struct squashfs_decompressor squashfs_xz_comp_ops = { + .init = squashfs_xz_init, + .free = squashfs_xz_free, + .decompress = squashfs_xz_uncompress, + .id = XZ_COMPRESSION, + .name = "xz", + .supported = 1 +}; |