2.6.30: add lzma support to squashfs through pcomp
[openwrt.git] / target / linux / generic-2.6 / patches-2.6.30 / 053-squashfs_lzma.patch
1 --- a/fs/squashfs/Kconfig
2 +++ b/fs/squashfs/Kconfig
3 @@ -2,7 +2,6 @@ config SQUASHFS
4         tristate "SquashFS 4.0 - Squashed file system support"
5         depends on BLOCK
6         select CRYPTO
7 -       select CRYPTO_ZLIB
8         help
9           Saying Y here includes support for SquashFS 4.0 (a Compressed
10           Read-Only File System).  Squashfs is a highly compressed read-only
11 @@ -37,6 +36,26 @@ config SQUASHFS_EMBEDDED
12  
13           If unsure, say N.
14  
15 +config SQUASHFS_SUPPORT_ZLIB
16 +       bool
17 +       prompt "Support ZLIB compression" if SQUASHFS_SUPPORT_LZMA
18 +       depends on SQUASHFS
19 +       select CRYPTO_ZLIB
20 +       default y
21 +       help
22 +         ZLIB is the default compression used in squashfs. If you are
23 +         using LZMA compression instead, you can remove support for ZLIB
24 +         entirely.
25 +
26 +config SQUASHFS_SUPPORT_LZMA
27 +       bool "Support LZMA compression"
28 +       depends on SQUASHFS
29 +       select CRYPTO_LZMA
30 +       help
31 +         By default SquashFS uses ZLIB compression, however (if your tools
32 +         support it, you can use LZMA instead, which saves space.
33 +
34 +
35  config SQUASHFS_FRAGMENT_CACHE_SIZE
36         int "Number of fragments cached" if SQUASHFS_EMBEDDED
37         depends on SQUASHFS
38 --- a/fs/squashfs/squashfs_fs.h
39 +++ b/fs/squashfs/squashfs_fs.h
40 @@ -212,6 +212,7 @@ struct meta_index {
41   * definitions for structures on disk
42   */
43  #define ZLIB_COMPRESSION        1
44 +#define LZMA_COMPRESSION        2
45  
46  struct squashfs_super_block {
47         __le32                  s_magic;
48 --- a/fs/squashfs/super.c
49 +++ b/fs/squashfs/super.c
50 @@ -47,13 +47,65 @@
51  #include "squashfs.h"
52  
53  
54 -#define SQUASHFS_CRYPTO_ALG    "zlib"
55 +static int squashfs_setup_zlib(struct squashfs_sb_info *msblk)
56 +{
57 +       int err = -EOPNOTSUPP;
58 +
59 +#ifdef CONFIG_SQUASHFS_SUPPORT_ZLIB
60 +       struct {
61 +               struct nlattr nla;
62 +               int val;
63 +       } params = {
64 +               .nla = {
65 +                       .nla_len        = nla_attr_size(sizeof(int)),
66 +                       .nla_type       = ZLIB_DECOMP_WINDOWBITS,
67 +               },
68 +               .val                    = DEF_WBITS,
69 +       };
70 +
71 +       msblk->tfm = crypto_alloc_pcomp("zlib", 0,
72 +                                       CRYPTO_ALG_ASYNC);
73 +       if (IS_ERR(msblk->tfm)) {
74 +               ERROR("Failed to load zlib crypto module\n");
75 +               return PTR_ERR(msblk->tfm);
76 +       }
77 +
78 +       err = crypto_decompress_setup(msblk->tfm, &params, sizeof(params));
79 +       if (err) {
80 +               ERROR("Failed to set up decompression parameters\n");
81 +               crypto_free_pcomp(msblk->tfm);
82 +       }
83 +#endif
84  
85 +       return err;
86 +}
87 +
88 +static int squashfs_setup_lzma(struct squashfs_sb_info *msblk)
89 +{
90 +       int err = -EOPNOTSUPP;
91 +
92 +#ifdef CONFIG_SQUASHFS_SUPPORT_LZMA
93 +       msblk->tfm = crypto_alloc_pcomp("lzma", 0,
94 +                                       CRYPTO_ALG_ASYNC);
95 +       if (IS_ERR(msblk->tfm)) {
96 +               ERROR("Failed to load lzma crypto module\n");
97 +               return PTR_ERR(msblk->tfm);
98 +       }
99 +
100 +       err = crypto_decompress_setup(msblk->tfm, NULL, 0);
101 +       if (err) {
102 +               ERROR("Failed to set up decompression parameters\n");
103 +               crypto_free_pcomp(msblk->tfm);
104 +       }
105 +#endif
106 +
107 +       return err;
108 +}
109  
110  static struct file_system_type squashfs_fs_type;
111  static struct super_operations squashfs_super_ops;
112  
113 -static int supported_squashfs_filesystem(short major, short minor, short comp)
114 +static int supported_squashfs_filesystem(short major, short minor)
115  {
116         if (major < SQUASHFS_MAJOR) {
117                 ERROR("Major/Minor mismatch, older Squashfs %d.%d "
118 @@ -66,9 +118,6 @@ static int supported_squashfs_filesystem
119                 return -EINVAL;
120         }
121  
122 -       if (comp != ZLIB_COMPRESSION)
123 -               return -EINVAL;
124 -
125         return 0;
126  }
127  
128 @@ -83,16 +132,6 @@ static int squashfs_fill_super(struct su
129         unsigned short flags;
130         unsigned int fragments;
131         u64 lookup_table_start;
132 -       struct {
133 -               struct nlattr nla;
134 -               int val;
135 -       } params = {
136 -               .nla = {
137 -                       .nla_len        = nla_attr_size(sizeof(int)),
138 -                       .nla_type       = ZLIB_DECOMP_WINDOWBITS,
139 -               },
140 -               .val                    = DEF_WBITS,
141 -       };
142         int err;
143  
144         TRACE("Entered squashfs_fill_superblock\n");
145 @@ -104,21 +143,6 @@ static int squashfs_fill_super(struct su
146         }
147         msblk = sb->s_fs_info;
148  
149 -       msblk->tfm = crypto_alloc_pcomp(SQUASHFS_CRYPTO_ALG, 0,
150 -                                       CRYPTO_ALG_ASYNC);
151 -       if (IS_ERR(msblk->tfm)) {
152 -               ERROR("Failed to load %s crypto module\n",
153 -                     SQUASHFS_CRYPTO_ALG);
154 -               err = PTR_ERR(msblk->tfm);
155 -               goto failed_pcomp;
156 -       }
157 -
158 -       err = crypto_decompress_setup(msblk->tfm, &params, sizeof(params));
159 -       if (err) {
160 -               ERROR("Failed to set up decompression parameters\n");
161 -               goto failure;
162 -       }
163 -
164         sblk = kzalloc(sizeof(*sblk), GFP_KERNEL);
165         if (sblk == NULL) {
166                 ERROR("Failed to allocate squashfs_super_block\n");
167 @@ -158,8 +182,21 @@ static int squashfs_fill_super(struct su
168  
169         /* Check the MAJOR & MINOR versions and compression type */
170         err = supported_squashfs_filesystem(le16_to_cpu(sblk->s_major),
171 -                       le16_to_cpu(sblk->s_minor),
172 -                       le16_to_cpu(sblk->compression));
173 +                       le16_to_cpu(sblk->s_minor));
174 +       if (err < 0)
175 +               goto failed_mount;
176 +
177 +       switch(le16_to_cpu(sblk->compression)) {
178 +       case ZLIB_COMPRESSION:
179 +               err = squashfs_setup_zlib(msblk);
180 +               break;
181 +       case LZMA_COMPRESSION:
182 +               err = squashfs_setup_lzma(msblk);
183 +               break;
184 +       default:
185 +               err = -EINVAL;
186 +               break;
187 +       }
188         if (err < 0)
189                 goto failed_mount;
190  
191 @@ -305,21 +342,16 @@ allocate_root:
192         return 0;
193  
194  failed_mount:
195 +       if (msblk->tfm)
196 +               crypto_free_pcomp(msblk->tfm);
197         squashfs_cache_delete(msblk->block_cache);
198         squashfs_cache_delete(msblk->fragment_cache);
199         squashfs_cache_delete(msblk->read_page);
200         kfree(msblk->inode_lookup_table);
201         kfree(msblk->fragment_index);
202         kfree(msblk->id_table);
203 -       crypto_free_pcomp(msblk->tfm);
204 -       kfree(sb->s_fs_info);
205 -       sb->s_fs_info = NULL;
206         kfree(sblk);
207 -       return err;
208 -
209  failure:
210 -       crypto_free_pcomp(msblk->tfm);
211 -failed_pcomp:
212         kfree(sb->s_fs_info);
213         sb->s_fs_info = NULL;
214         return err;