From 6feed0b491d7f433abca608d4a1d872045187774 Mon Sep 17 00:00:00 2001 From: Enrico Jorns Date: Tue, 4 Oct 2016 12:10:46 +0200 Subject: fs: squashfs: port zlib compression support from kernel As this is the default compression method for squashfs, make this the default in kconfig selection, too Signed-off-by: Enrico Jorns Signed-off-by: Sascha Hauer --- fs/squashfs/Kconfig | 10 ++++ fs/squashfs/Makefile | 1 + fs/squashfs/zlib_wrapper.c | 132 +++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 143 insertions(+) create mode 100644 fs/squashfs/zlib_wrapper.c (limited to 'fs/squashfs') diff --git a/fs/squashfs/Kconfig b/fs/squashfs/Kconfig index 928e3bb546..085bfb6448 100644 --- a/fs/squashfs/Kconfig +++ b/fs/squashfs/Kconfig @@ -17,6 +17,16 @@ menuconfig FS_SQUASHFS embedded systems where low overhead is needed. Further information and tools are available from http://squashfs.sourceforge.net. +config SQUASHFS_ZLIB + bool + depends on FS_SQUASHFS + depends on ZLIB + default y + +if !SQUASHFS_ZLIB + comment "ZLIB support disabled" +endif + config SQUASHFS_LZ4 bool depends on FS_SQUASHFS diff --git a/fs/squashfs/Makefile b/fs/squashfs/Makefile index 8590b09ce6..7976e3fe5c 100644 --- a/fs/squashfs/Makefile +++ b/fs/squashfs/Makefile @@ -13,3 +13,4 @@ obj-y += super.o obj-$(CONFIG_SQUASHFS_XZ) += xz_wrapper.o obj-$(CONFIG_SQUASHFS_LZO) += lzo_wrapper.o obj-$(CONFIG_SQUASHFS_LZ4) += lz4_wrapper.o +obj-$(CONFIG_SQUASHFS_ZLIB) += zlib_wrapper.o diff --git a/fs/squashfs/zlib_wrapper.c b/fs/squashfs/zlib_wrapper.c new file mode 100644 index 0000000000..f422515e7c --- /dev/null +++ b/fs/squashfs/zlib_wrapper.c @@ -0,0 +1,132 @@ +/* + * Squashfs - a compressed read only filesystem for Linux + * + * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 + * Phillip Lougher + * + * 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. + * + * zlib_wrapper.c + */ + + +#include +#include + +#include "squashfs_fs.h" +#include "squashfs_fs_sb.h" +#include "squashfs.h" +#include "decompressor.h" +#include "page_actor.h" + +static void *zlib_init(struct squashfs_sb_info *dummy, void *buff) +{ + z_stream *stream = kmalloc(sizeof(z_stream), GFP_KERNEL); + if (stream == NULL) + goto failed; + stream->workspace = vmalloc(zlib_inflate_workspacesize()); + if (stream->workspace == NULL) + goto failed; + + return stream; + +failed: + ERROR("Failed to allocate zlib workspace\n"); + kfree(stream); + return ERR_PTR(-ENOMEM); +} + + +static void zlib_free(void *strm) +{ + z_stream *stream = strm; + + if (stream) + vfree(stream->workspace); + kfree(stream); +} + + +static int zlib_uncompress(struct squashfs_sb_info *msblk, void *strm, + char **bh, int b, int offset, int length, + struct squashfs_page_actor *output) +{ + int zlib_err, zlib_init = 0, k = 0; + z_stream *stream = strm; + + stream->avail_out = PAGE_CACHE_SIZE; + stream->next_out = squashfs_first_page(output); + stream->avail_in = 0; + + do { + if (stream->avail_in == 0 && k < b) { + int avail = min(length, msblk->devblksize - offset); + length -= avail; + stream->next_in = bh[k] + offset; + stream->avail_in = avail; + offset = 0; + } + + if (stream->avail_out == 0) { + stream->next_out = squashfs_next_page(output); + if (stream->next_out != NULL) + stream->avail_out = PAGE_CACHE_SIZE; + } + + if (!zlib_init) { + zlib_err = zlib_inflateInit(stream); + if (zlib_err != Z_OK) { + squashfs_finish_page(output); + goto out; + } + zlib_init = 1; + } + + zlib_err = zlib_inflate(stream, Z_SYNC_FLUSH); + + if (stream->avail_in == 0 && k < b) + kfree(bh[k++]); + } while (zlib_err == Z_OK); + + squashfs_finish_page(output); + + if (zlib_err != Z_STREAM_END) + goto out; + + zlib_err = zlib_inflateEnd(stream); + if (zlib_err != Z_OK) + goto out; + + if (k < b) + goto out; + + return stream->total_out; + +out: + for (; k < b; k++) + kfree(bh[k]); + + return -EIO; +} + +const struct squashfs_decompressor squashfs_zlib_comp_ops = { + .init = zlib_init, + .free = zlib_free, + .decompress = zlib_uncompress, + .id = ZLIB_COMPRESSION, + .name = "zlib", + .supported = 1 +}; + -- cgit v1.2.3