Root/
1 | /* |
2 | * JFFS2 -- Journalling Flash File System, Version 2. |
3 | * |
4 | * Copyright © 2001-2007 Red Hat, Inc. |
5 | * |
6 | * Created by David Woodhouse <dwmw2@infradead.org> |
7 | * |
8 | * For licensing information, see the file 'LICENCE' in this directory. |
9 | * |
10 | */ |
11 | |
12 | #if !defined(__KERNEL__) && !defined(__ECOS) |
13 | #error "The userspace support got too messy and was removed. Update your mkfs.jffs2" |
14 | #endif |
15 | |
16 | #include <linux/kernel.h> |
17 | #include <linux/slab.h> |
18 | #include <linux/zlib.h> |
19 | #include <linux/zutil.h> |
20 | #include "nodelist.h" |
21 | #include "compr.h" |
22 | |
23 | /* Plan: call deflate() with avail_in == *sourcelen, |
24 | avail_out = *dstlen - 12 and flush == Z_FINISH. |
25 | If it doesn't manage to finish, call it again with |
26 | avail_in == 0 and avail_out set to the remaining 12 |
27 | bytes for it to clean up. |
28 | Q: Is 12 bytes sufficient? |
29 | */ |
30 | #define STREAM_END_SPACE 12 |
31 | |
32 | static DEFINE_MUTEX(deflate_mutex); |
33 | static DEFINE_MUTEX(inflate_mutex); |
34 | static z_stream inf_strm, def_strm; |
35 | |
36 | #ifdef __KERNEL__ /* Linux-only */ |
37 | #include <linux/vmalloc.h> |
38 | #include <linux/init.h> |
39 | #include <linux/mutex.h> |
40 | |
41 | static int __init alloc_workspaces(void) |
42 | { |
43 | def_strm.workspace = vmalloc(zlib_deflate_workspacesize()); |
44 | if (!def_strm.workspace) { |
45 | printk(KERN_WARNING "Failed to allocate %d bytes for deflate workspace\n", zlib_deflate_workspacesize()); |
46 | return -ENOMEM; |
47 | } |
48 | D1(printk(KERN_DEBUG "Allocated %d bytes for deflate workspace\n", zlib_deflate_workspacesize())); |
49 | inf_strm.workspace = vmalloc(zlib_inflate_workspacesize()); |
50 | if (!inf_strm.workspace) { |
51 | printk(KERN_WARNING "Failed to allocate %d bytes for inflate workspace\n", zlib_inflate_workspacesize()); |
52 | vfree(def_strm.workspace); |
53 | return -ENOMEM; |
54 | } |
55 | D1(printk(KERN_DEBUG "Allocated %d bytes for inflate workspace\n", zlib_inflate_workspacesize())); |
56 | return 0; |
57 | } |
58 | |
59 | static void free_workspaces(void) |
60 | { |
61 | vfree(def_strm.workspace); |
62 | vfree(inf_strm.workspace); |
63 | } |
64 | #else |
65 | #define alloc_workspaces() (0) |
66 | #define free_workspaces() do { } while(0) |
67 | #endif /* __KERNEL__ */ |
68 | |
69 | static int jffs2_zlib_compress(unsigned char *data_in, |
70 | unsigned char *cpage_out, |
71 | uint32_t *sourcelen, uint32_t *dstlen, |
72 | void *model) |
73 | { |
74 | int ret; |
75 | |
76 | if (*dstlen <= STREAM_END_SPACE) |
77 | return -1; |
78 | |
79 | mutex_lock(&deflate_mutex); |
80 | |
81 | if (Z_OK != zlib_deflateInit(&def_strm, 3)) { |
82 | printk(KERN_WARNING "deflateInit failed\n"); |
83 | mutex_unlock(&deflate_mutex); |
84 | return -1; |
85 | } |
86 | |
87 | def_strm.next_in = data_in; |
88 | def_strm.total_in = 0; |
89 | |
90 | def_strm.next_out = cpage_out; |
91 | def_strm.total_out = 0; |
92 | |
93 | while (def_strm.total_out < *dstlen - STREAM_END_SPACE && def_strm.total_in < *sourcelen) { |
94 | def_strm.avail_out = *dstlen - (def_strm.total_out + STREAM_END_SPACE); |
95 | def_strm.avail_in = min((unsigned)(*sourcelen-def_strm.total_in), def_strm.avail_out); |
96 | D1(printk(KERN_DEBUG "calling deflate with avail_in %d, avail_out %d\n", |
97 | def_strm.avail_in, def_strm.avail_out)); |
98 | ret = zlib_deflate(&def_strm, Z_PARTIAL_FLUSH); |
99 | D1(printk(KERN_DEBUG "deflate returned with avail_in %d, avail_out %d, total_in %ld, total_out %ld\n", |
100 | def_strm.avail_in, def_strm.avail_out, def_strm.total_in, def_strm.total_out)); |
101 | if (ret != Z_OK) { |
102 | D1(printk(KERN_DEBUG "deflate in loop returned %d\n", ret)); |
103 | zlib_deflateEnd(&def_strm); |
104 | mutex_unlock(&deflate_mutex); |
105 | return -1; |
106 | } |
107 | } |
108 | def_strm.avail_out += STREAM_END_SPACE; |
109 | def_strm.avail_in = 0; |
110 | ret = zlib_deflate(&def_strm, Z_FINISH); |
111 | zlib_deflateEnd(&def_strm); |
112 | |
113 | if (ret != Z_STREAM_END) { |
114 | D1(printk(KERN_DEBUG "final deflate returned %d\n", ret)); |
115 | ret = -1; |
116 | goto out; |
117 | } |
118 | |
119 | if (def_strm.total_out >= def_strm.total_in) { |
120 | D1(printk(KERN_DEBUG "zlib compressed %ld bytes into %ld; failing\n", |
121 | def_strm.total_in, def_strm.total_out)); |
122 | ret = -1; |
123 | goto out; |
124 | } |
125 | |
126 | D1(printk(KERN_DEBUG "zlib compressed %ld bytes into %ld\n", |
127 | def_strm.total_in, def_strm.total_out)); |
128 | |
129 | *dstlen = def_strm.total_out; |
130 | *sourcelen = def_strm.total_in; |
131 | ret = 0; |
132 | out: |
133 | mutex_unlock(&deflate_mutex); |
134 | return ret; |
135 | } |
136 | |
137 | static int jffs2_zlib_decompress(unsigned char *data_in, |
138 | unsigned char *cpage_out, |
139 | uint32_t srclen, uint32_t destlen, |
140 | void *model) |
141 | { |
142 | int ret; |
143 | int wbits = MAX_WBITS; |
144 | |
145 | mutex_lock(&inflate_mutex); |
146 | |
147 | inf_strm.next_in = data_in; |
148 | inf_strm.avail_in = srclen; |
149 | inf_strm.total_in = 0; |
150 | |
151 | inf_strm.next_out = cpage_out; |
152 | inf_strm.avail_out = destlen; |
153 | inf_strm.total_out = 0; |
154 | |
155 | /* If it's deflate, and it's got no preset dictionary, then |
156 | we can tell zlib to skip the adler32 check. */ |
157 | if (srclen > 2 && !(data_in[1] & PRESET_DICT) && |
158 | ((data_in[0] & 0x0f) == Z_DEFLATED) && |
159 | !(((data_in[0]<<8) + data_in[1]) % 31)) { |
160 | |
161 | D2(printk(KERN_DEBUG "inflate skipping adler32\n")); |
162 | wbits = -((data_in[0] >> 4) + 8); |
163 | inf_strm.next_in += 2; |
164 | inf_strm.avail_in -= 2; |
165 | } else { |
166 | /* Let this remain D1 for now -- it should never happen */ |
167 | D1(printk(KERN_DEBUG "inflate not skipping adler32\n")); |
168 | } |
169 | |
170 | |
171 | if (Z_OK != zlib_inflateInit2(&inf_strm, wbits)) { |
172 | printk(KERN_WARNING "inflateInit failed\n"); |
173 | mutex_unlock(&inflate_mutex); |
174 | return 1; |
175 | } |
176 | |
177 | while((ret = zlib_inflate(&inf_strm, Z_FINISH)) == Z_OK) |
178 | ; |
179 | if (ret != Z_STREAM_END) { |
180 | printk(KERN_NOTICE "inflate returned %d\n", ret); |
181 | } |
182 | zlib_inflateEnd(&inf_strm); |
183 | mutex_unlock(&inflate_mutex); |
184 | return 0; |
185 | } |
186 | |
187 | static struct jffs2_compressor jffs2_zlib_comp = { |
188 | .priority = JFFS2_ZLIB_PRIORITY, |
189 | .name = "zlib", |
190 | .compr = JFFS2_COMPR_ZLIB, |
191 | .compress = &jffs2_zlib_compress, |
192 | .decompress = &jffs2_zlib_decompress, |
193 | #ifdef JFFS2_ZLIB_DISABLED |
194 | .disabled = 1, |
195 | #else |
196 | .disabled = 0, |
197 | #endif |
198 | }; |
199 | |
200 | int __init jffs2_zlib_init(void) |
201 | { |
202 | int ret; |
203 | |
204 | ret = alloc_workspaces(); |
205 | if (ret) |
206 | return ret; |
207 | |
208 | ret = jffs2_register_compressor(&jffs2_zlib_comp); |
209 | if (ret) |
210 | free_workspaces(); |
211 | |
212 | return ret; |
213 | } |
214 | |
215 | void jffs2_zlib_exit(void) |
216 | { |
217 | jffs2_unregister_compressor(&jffs2_zlib_comp); |
218 | free_workspaces(); |
219 | } |
220 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
jz-3.13
jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9