Squashfs: move zlib decompression wrapper code into a separate file (e6a6d379) · Commits · git / linux-net

fs/squashfs/Makefile

+1 −1

Original line number	Diff line number	Diff line
		@@ -4,4 +4,4 @@

		obj-$(CONFIG_SQUASHFS) += squashfs.o
		squashfs-y += block.o cache.o dir.o export.o file.o fragment.o id.o inode.o
		squashfs-y += namei.o super.o symlink.o
		squashfs-y += namei.o super.o symlink.o zlib_wrapper.o

fs/squashfs/block.c

+4 −70

Original line number	Diff line number	Diff line
		@@ -29,7 +29,6 @@
		#include <linux/fs.h>
		#include <linux/vfs.h>
		#include <linux/slab.h>
		#include <linux/mutex.h>
		#include <linux/string.h>
		#include <linux/buffer_head.h>
		#include <linux/zlib.h>
		@@ -153,72 +152,10 @@ int squashfs_read_data(struct super_block sb, void *buffer, u64 index,
		}

		if (compressed) {
		int zlib_err = 0, zlib_init = 0;

		/*
		* Uncompress block.
		*/

		mutex_lock(&msblk->read_data_mutex);

		msblk->stream.avail_out = 0;
		msblk->stream.avail_in = 0;

		bytes = length;
		do {
		if (msblk->stream.avail_in == 0 && k < b) {
		avail = min(bytes, msblk->devblksize - offset);
		bytes -= avail;
		wait_on_buffer(bh[k]);
		if (!buffer_uptodate(bh[k]))
		goto release_mutex;

		if (avail == 0) {
		offset = 0;
		put_bh(bh[k++]);
		continue;
		}

		msblk->stream.next_in = bh[k]->b_data + offset;
		msblk->stream.avail_in = avail;
		offset = 0;
		}

		if (msblk->stream.avail_out == 0 && page < pages) {
		msblk->stream.next_out = buffer[page++];
		msblk->stream.avail_out = PAGE_CACHE_SIZE;
		}

		if (!zlib_init) {
		zlib_err = zlib_inflateInit(&msblk->stream);
		if (zlib_err != Z_OK) {
		ERROR("zlib_inflateInit returned"
		" unexpected result 0x%x,"
		" srclength %d\n", zlib_err,
		srclength);
		goto release_mutex;
		}
		zlib_init = 1;
		}

		zlib_err = zlib_inflate(&msblk->stream, Z_SYNC_FLUSH);

		if (msblk->stream.avail_in == 0 && k < b)
		put_bh(bh[k++]);
		} while (zlib_err == Z_OK);

		if (zlib_err != Z_STREAM_END) {
		ERROR("zlib_inflate error, data probably corrupt\n");
		goto release_mutex;
		}

		zlib_err = zlib_inflateEnd(&msblk->stream);
		if (zlib_err != Z_OK) {
		ERROR("zlib_inflate error, data probably corrupt\n");
		goto release_mutex;
		}
		length = msblk->stream.total_out;
		mutex_unlock(&msblk->read_data_mutex);
		length = squashfs_zlib_uncompress(msblk, buffer, bh, b, offset,
		length, srclength, pages);
		if (length < 0)
		goto read_failure;
		} else {
		/*
		* Block is uncompressed.
		@@ -255,9 +192,6 @@ int squashfs_read_data(struct super_block sb, void *buffer, u64 index,
		kfree(bh);
		return length;

		release_mutex:
		mutex_unlock(&msblk->read_data_mutex);

		block_release:
		for (; k < b; k++)
		put_bh(bh[k]);

fs/squashfs/squashfs.h

+4 −0

Original line number	Diff line number	Diff line
		@@ -70,6 +70,10 @@ extern struct inode squashfs_iget(struct super_block , long long,
		unsigned int);
		extern int squashfs_read_inode(struct inode *, long long);

		/* zlib_wrapper.c */
		extern int squashfs_zlib_uncompress(struct squashfs_sb_info , void *,
		struct buffer_head **, int, int, int, int, int);

		/*
		* Inodes and files operations
		*/

fs/squashfs/zlib_wrapper.c

0 → 100644

+109 −0

Original line number	Diff line number	Diff line
		/*
		* Squashfs - a compressed read only filesystem for Linux
		*
		* Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
		* 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.
		*
		* zlib_wrapper.c
		*/


		#include <linux/mutex.h>
		#include <linux/buffer_head.h>
		#include <linux/zlib.h>

		#include "squashfs_fs.h"
		#include "squashfs_fs_sb.h"
		#include "squashfs_fs_i.h"
		#include "squashfs.h"

		int squashfs_zlib_uncompress(struct squashfs_sb_info msblk, void *buffer,
		struct buffer_head **bh, int b, int offset, int length, int srclength,
		int pages)
		{
		int zlib_err = 0, zlib_init = 0;
		int avail, bytes, k = 0, page = 0;

		mutex_lock(&msblk->read_data_mutex);

		msblk->stream.avail_out = 0;
		msblk->stream.avail_in = 0;

		bytes = length;
		do {
		if (msblk->stream.avail_in == 0 && k < b) {
		avail = min(bytes, msblk->devblksize - offset);
		bytes -= avail;
		wait_on_buffer(bh[k]);
		if (!buffer_uptodate(bh[k]))
		goto release_mutex;

		if (avail == 0) {
		offset = 0;
		put_bh(bh[k++]);
		continue;
		}

		msblk->stream.next_in = bh[k]->b_data + offset;
		msblk->stream.avail_in = avail;
		offset = 0;
		}

		if (msblk->stream.avail_out == 0 && page < pages) {
		msblk->stream.next_out = buffer[page++];
		msblk->stream.avail_out = PAGE_CACHE_SIZE;
		}

		if (!zlib_init) {
		zlib_err = zlib_inflateInit(&msblk->stream);
		if (zlib_err != Z_OK) {
		ERROR("zlib_inflateInit returned unexpected "
		"result 0x%x, srclength %d\n",
		zlib_err, srclength);
		goto release_mutex;
		}
		zlib_init = 1;
		}

		zlib_err = zlib_inflate(&msblk->stream, Z_SYNC_FLUSH);

		if (msblk->stream.avail_in == 0 && k < b)
		put_bh(bh[k++]);
		} while (zlib_err == Z_OK);

		if (zlib_err != Z_STREAM_END) {
		ERROR("zlib_inflate error, data probably corrupt\n");
		goto release_mutex;
		}

		zlib_err = zlib_inflateEnd(&msblk->stream);
		if (zlib_err != Z_OK) {
		ERROR("zlib_inflate error, data probably corrupt\n");
		goto release_mutex;
		}

		mutex_unlock(&msblk->read_data_mutex);
		return msblk->stream.total_out;

		release_mutex:
		mutex_unlock(&msblk->read_data_mutex);

		for (; k < b; k++)
		put_bh(bh[k]);

		return -EIO;
		}