Root/target/linux/generic-2.6/patches-2.6.30/001-squashfs_move_zlib_decomp.patch

1From 6c4419d997d4431bb62e73475cd6b084e83efbd1 Mon Sep 17 00:00:00 2001
2From: Phillip Lougher <phillip@lougher.demon.co.uk>
3Date: Tue, 22 Sep 2009 19:25:24 +0100
4Subject: [PATCH] Squashfs: move zlib decompression wrapper code into a separate file
5
6Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
7---
8 fs/squashfs/Makefile | 2 +-
9 fs/squashfs/block.c | 74 ++----------------------------
10 fs/squashfs/squashfs.h | 4 ++
11 fs/squashfs/zlib_wrapper.c | 109 ++++++++++++++++++++++++++++++++++++++++++++
12 4 files changed, 118 insertions(+), 71 deletions(-)
13 create mode 100644 fs/squashfs/zlib_wrapper.c
14
15--- a/fs/squashfs/Makefile
16+++ b/fs/squashfs/Makefile
17@@ -4,4 +4,4 @@
18 
19 obj-$(CONFIG_SQUASHFS) += squashfs.o
20 squashfs-y += block.o cache.o dir.o export.o file.o fragment.o id.o inode.o
21-squashfs-y += namei.o super.o symlink.o
22+squashfs-y += namei.o super.o symlink.o zlib_wrapper.o
23--- a/fs/squashfs/block.c
24+++ b/fs/squashfs/block.c
25@@ -29,7 +29,6 @@
26 #include <linux/fs.h>
27 #include <linux/vfs.h>
28 #include <linux/slab.h>
29-#include <linux/mutex.h>
30 #include <linux/string.h>
31 #include <linux/buffer_head.h>
32 #include <linux/zlib.h>
33@@ -153,72 +152,10 @@ int squashfs_read_data(struct super_bloc
34     }
35 
36     if (compressed) {
37- int zlib_err = 0, zlib_init = 0;
38-
39- /*
40- * Uncompress block.
41- */
42-
43- mutex_lock(&msblk->read_data_mutex);
44-
45- msblk->stream.avail_out = 0;
46- msblk->stream.avail_in = 0;
47-
48- bytes = length;
49- do {
50- if (msblk->stream.avail_in == 0 && k < b) {
51- avail = min(bytes, msblk->devblksize - offset);
52- bytes -= avail;
53- wait_on_buffer(bh[k]);
54- if (!buffer_uptodate(bh[k]))
55- goto release_mutex;
56-
57- if (avail == 0) {
58- offset = 0;
59- put_bh(bh[k++]);
60- continue;
61- }
62-
63- msblk->stream.next_in = bh[k]->b_data + offset;
64- msblk->stream.avail_in = avail;
65- offset = 0;
66- }
67-
68- if (msblk->stream.avail_out == 0 && page < pages) {
69- msblk->stream.next_out = buffer[page++];
70- msblk->stream.avail_out = PAGE_CACHE_SIZE;
71- }
72-
73- if (!zlib_init) {
74- zlib_err = zlib_inflateInit(&msblk->stream);
75- if (zlib_err != Z_OK) {
76- ERROR("zlib_inflateInit returned"
77- " unexpected result 0x%x,"
78- " srclength %d\n", zlib_err,
79- srclength);
80- goto release_mutex;
81- }
82- zlib_init = 1;
83- }
84-
85- zlib_err = zlib_inflate(&msblk->stream, Z_SYNC_FLUSH);
86-
87- if (msblk->stream.avail_in == 0 && k < b)
88- put_bh(bh[k++]);
89- } while (zlib_err == Z_OK);
90-
91- if (zlib_err != Z_STREAM_END) {
92- ERROR("zlib_inflate error, data probably corrupt\n");
93- goto release_mutex;
94- }
95-
96- zlib_err = zlib_inflateEnd(&msblk->stream);
97- if (zlib_err != Z_OK) {
98- ERROR("zlib_inflate error, data probably corrupt\n");
99- goto release_mutex;
100- }
101- length = msblk->stream.total_out;
102- mutex_unlock(&msblk->read_data_mutex);
103+ length = zlib_uncompress(msblk, buffer, bh, b, offset, length,
104+ srclength, pages);
105+ if (length < 0)
106+ goto read_failure;
107     } else {
108         /*
109          * Block is uncompressed.
110@@ -255,9 +192,6 @@ int squashfs_read_data(struct super_bloc
111     kfree(bh);
112     return length;
113 
114-release_mutex:
115- mutex_unlock(&msblk->read_data_mutex);
116-
117 block_release:
118     for (; k < b; k++)
119         put_bh(bh[k]);
120--- a/fs/squashfs/squashfs.h
121+++ b/fs/squashfs/squashfs.h
122@@ -70,6 +70,10 @@ extern struct inode *squashfs_iget(struc
123                 unsigned int);
124 extern int squashfs_read_inode(struct inode *, long long);
125 
126+/* zlib_wrapper.c */
127+extern int zlib_uncompress(struct squashfs_sb_info *, void **,
128+ struct buffer_head **, int, int, int, int, int);
129+
130 /*
131  * Inodes and files operations
132  */
133--- /dev/null
134+++ b/fs/squashfs/zlib_wrapper.c
135@@ -0,0 +1,109 @@
136+/*
137+ * Squashfs - a compressed read only filesystem for Linux
138+ *
139+ * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
140+ * Phillip Lougher <phillip@lougher.demon.co.uk>
141+ *
142+ * This program is free software; you can redistribute it and/or
143+ * modify it under the terms of the GNU General Public License
144+ * as published by the Free Software Foundation; either version 2,
145+ * or (at your option) any later version.
146+ *
147+ * This program is distributed in the hope that it will be useful,
148+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
149+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
150+ * GNU General Public License for more details.
151+ *
152+ * You should have received a copy of the GNU General Public License
153+ * along with this program; if not, write to the Free Software
154+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
155+ *
156+ * zlib_wrapper.c
157+ */
158+
159+
160+#include <linux/mutex.h>
161+#include <linux/buffer_head.h>
162+#include <linux/zlib.h>
163+
164+#include "squashfs_fs.h"
165+#include "squashfs_fs_sb.h"
166+#include "squashfs_fs_i.h"
167+#include "squashfs.h"
168+
169+int zlib_uncompress(struct squashfs_sb_info *msblk, void **buffer,
170+ struct buffer_head **bh, int b, int offset, int length, int srclength,
171+ int pages)
172+{
173+ int zlib_err = 0, zlib_init = 0;
174+ int avail, bytes, k = 0, page = 0;
175+
176+ mutex_lock(&msblk->read_data_mutex);
177+
178+ msblk->stream.avail_out = 0;
179+ msblk->stream.avail_in = 0;
180+
181+ bytes = length;
182+ do {
183+ if (msblk->stream.avail_in == 0 && k < b) {
184+ avail = min(bytes, msblk->devblksize - offset);
185+ bytes -= avail;
186+ wait_on_buffer(bh[k]);
187+ if (!buffer_uptodate(bh[k]))
188+ goto release_mutex;
189+
190+ if (avail == 0) {
191+ offset = 0;
192+ put_bh(bh[k++]);
193+ continue;
194+ }
195+
196+ msblk->stream.next_in = bh[k]->b_data + offset;
197+ msblk->stream.avail_in = avail;
198+ offset = 0;
199+ }
200+
201+ if (msblk->stream.avail_out == 0 && page < pages) {
202+ msblk->stream.next_out = buffer[page++];
203+ msblk->stream.avail_out = PAGE_CACHE_SIZE;
204+ }
205+
206+ if (!zlib_init) {
207+ zlib_err = zlib_inflateInit(&msblk->stream);
208+ if (zlib_err != Z_OK) {
209+ ERROR("zlib_inflateInit returned unexpected "
210+ "result 0x%x, srclength %d\n",
211+ zlib_err, srclength);
212+ goto release_mutex;
213+ }
214+ zlib_init = 1;
215+ }
216+
217+ zlib_err = zlib_inflate(&msblk->stream, Z_SYNC_FLUSH);
218+
219+ if (msblk->stream.avail_in == 0 && k < b)
220+ put_bh(bh[k++]);
221+ } while (zlib_err == Z_OK);
222+
223+ if (zlib_err != Z_STREAM_END) {
224+ ERROR("zlib_inflate error, data probably corrupt\n");
225+ goto release_mutex;
226+ }
227+
228+ zlib_err = zlib_inflateEnd(&msblk->stream);
229+ if (zlib_err != Z_OK) {
230+ ERROR("zlib_inflate error, data probably corrupt\n");
231+ goto release_mutex;
232+ }
233+
234+ mutex_unlock(&msblk->read_data_mutex);
235+ return msblk->stream.total_out;
236+
237+release_mutex:
238+ mutex_unlock(&msblk->read_data_mutex);
239+
240+ for (; k < b; k++)
241+ put_bh(bh[k]);
242+
243+ return -EIO;
244+}
245

Archive Download this file

Branches:
backfire
history
master
release_2010-11-17
release_2010-12-14
release_2011-02-23
release_2011-05-28
release_2011-08-27
release_2011-11-13
release_2012-03-18
release_2012-04-09
release_2012-10-11
uclibc_nptl



interactive