diff options
author | Richard Purdie <rpurdie@openedhand.com> | 2007-07-10 05:28:36 -0400 |
---|---|---|
committer | David Woodhouse <dwmw2@infradead.org> | 2007-07-11 10:03:53 -0400 |
commit | c799aca31bfe61ba3a91133acf5a13a0773087d4 (patch) | |
tree | d05f44fbec08e26fd52b8b1f4c7b5d162cfe3c31 /fs/jffs2/compr_lzo.c | |
parent | 8691a729a2a3d739ee40a577053157393450aabd (diff) |
[JFFS2] Add LZO compression support.
Add LZO1X compression/decompression support to jffs2.
LZO's interface doesn't entirely match that required by jffs2 so a
buffer and memcpy is unavoidable.
Signed-off-by: Richard Purdie <rpurdie@openedhand.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Diffstat (limited to 'fs/jffs2/compr_lzo.c')
-rw-r--r-- | fs/jffs2/compr_lzo.c | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/fs/jffs2/compr_lzo.c b/fs/jffs2/compr_lzo.c new file mode 100644 index 000000000000..47b045797e42 --- /dev/null +++ b/fs/jffs2/compr_lzo.c | |||
@@ -0,0 +1,108 @@ | |||
1 | /* | ||
2 | * JFFS2 -- Journalling Flash File System, Version 2. | ||
3 | * | ||
4 | * Copyright © 2007 Nokia Corporation. All rights reserved. | ||
5 | * | ||
6 | * Created by Richard Purdie <rpurdie@openedhand.com> | ||
7 | * | ||
8 | * For licensing information, see the file 'LICENCE' in this directory. | ||
9 | * | ||
10 | */ | ||
11 | |||
12 | #include <linux/kernel.h> | ||
13 | #include <linux/sched.h> | ||
14 | #include <linux/slab.h> | ||
15 | #include <linux/vmalloc.h> | ||
16 | #include <linux/init.h> | ||
17 | #include <linux/lzo.h> | ||
18 | #include "compr.h" | ||
19 | |||
20 | static void *lzo_mem; | ||
21 | static void *lzo_compress_buf; | ||
22 | static DEFINE_MUTEX(deflate_mutex); | ||
23 | |||
24 | static void free_workspace(void) | ||
25 | { | ||
26 | vfree(lzo_mem); | ||
27 | vfree(lzo_compress_buf); | ||
28 | } | ||
29 | |||
30 | static int __init alloc_workspace(void) | ||
31 | { | ||
32 | lzo_mem = vmalloc(LZO1X_MEM_COMPRESS); | ||
33 | lzo_compress_buf = vmalloc(lzo1x_worst_compress(PAGE_SIZE)); | ||
34 | |||
35 | if (!lzo_mem || !lzo_compress_buf) { | ||
36 | printk(KERN_WARNING "Failed to allocate lzo deflate workspace\n"); | ||
37 | free_workspace(); | ||
38 | return -ENOMEM; | ||
39 | } | ||
40 | |||
41 | return 0; | ||
42 | } | ||
43 | |||
44 | static int jffs2_lzo_compress(unsigned char *data_in, unsigned char *cpage_out, | ||
45 | uint32_t *sourcelen, uint32_t *dstlen, void *model) | ||
46 | { | ||
47 | size_t compress_size; | ||
48 | int ret; | ||
49 | |||
50 | mutex_lock(&deflate_mutex); | ||
51 | ret = lzo1x_1_compress(data_in, *sourcelen, lzo_compress_buf, &compress_size, lzo_mem); | ||
52 | mutex_unlock(&deflate_mutex); | ||
53 | |||
54 | if (ret != LZO_E_OK) | ||
55 | return -1; | ||
56 | |||
57 | if (compress_size > *dstlen) | ||
58 | return -1; | ||
59 | |||
60 | memcpy(cpage_out, lzo_compress_buf, compress_size); | ||
61 | *dstlen = compress_size; | ||
62 | |||
63 | return 0; | ||
64 | } | ||
65 | |||
66 | static int jffs2_lzo_decompress(unsigned char *data_in, unsigned char *cpage_out, | ||
67 | uint32_t srclen, uint32_t destlen, void *model) | ||
68 | { | ||
69 | size_t dl = destlen; | ||
70 | int ret; | ||
71 | |||
72 | ret = lzo1x_decompress_safe(data_in, srclen, cpage_out, &dl); | ||
73 | |||
74 | if (ret != LZO_E_OK || dl != destlen) | ||
75 | return -1; | ||
76 | |||
77 | return 0; | ||
78 | } | ||
79 | |||
80 | static struct jffs2_compressor jffs2_lzo_comp = { | ||
81 | .priority = JFFS2_LZO_PRIORITY, | ||
82 | .name = "lzo", | ||
83 | .compr = JFFS2_COMPR_LZO, | ||
84 | .compress = &jffs2_lzo_compress, | ||
85 | .decompress = &jffs2_lzo_decompress, | ||
86 | .disabled = 0, | ||
87 | }; | ||
88 | |||
89 | int __init jffs2_lzo_init(void) | ||
90 | { | ||
91 | int ret; | ||
92 | |||
93 | ret = alloc_workspace(); | ||
94 | if (ret < 0) | ||
95 | return ret; | ||
96 | |||
97 | ret = jffs2_register_compressor(&jffs2_lzo_comp); | ||
98 | if (ret) | ||
99 | free_workspace(); | ||
100 | |||
101 | return ret; | ||
102 | } | ||
103 | |||
104 | void jffs2_lzo_exit(void) | ||
105 | { | ||
106 | jffs2_unregister_compressor(&jffs2_lzo_comp); | ||
107 | free_workspace(); | ||
108 | } | ||