unlzma: fix a race condition and add some optimizations to improve performance also...
[oweals/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_UNLZMA
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 +47,76 @@
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 +       struct {
94 +               struct nlattr nla;
95 +               int val;
96 +       } params = {
97 +               .nla = {
98 +                       .nla_len        = nla_attr_size(sizeof(int)),
99 +                       .nla_type       = UNLZMA_DECOMP_OUT_BUFFERS,
100 +               },
101 +               .val = (msblk->block_size / PAGE_CACHE_SIZE) + 1
102 +       };
103  
104 +       msblk->tfm = crypto_alloc_pcomp("lzma", 0,
105 +                                       CRYPTO_ALG_ASYNC);
106 +       if (IS_ERR(msblk->tfm)) {
107 +               ERROR("Failed to load lzma crypto module\n");
108 +               return PTR_ERR(msblk->tfm);
109 +       }
110 +
111 +       err = crypto_decompress_setup(msblk->tfm, &params, sizeof(params));
112 +       if (err) {
113 +               ERROR("Failed to set up decompression parameters\n");
114 +               crypto_free_pcomp(msblk->tfm);
115 +       }
116 +#endif
117 +
118 +       return err;
119 +}
120  
121  static struct file_system_type squashfs_fs_type;
122  static struct super_operations squashfs_super_ops;
123  
124 -static int supported_squashfs_filesystem(short major, short minor, short comp)
125 +static int supported_squashfs_filesystem(short major, short minor)
126  {
127         if (major < SQUASHFS_MAJOR) {
128                 ERROR("Major/Minor mismatch, older Squashfs %d.%d "
129 @@ -66,9 +129,6 @@ static int supported_squashfs_filesystem
130                 return -EINVAL;
131         }
132  
133 -       if (comp != ZLIB_COMPRESSION)
134 -               return -EINVAL;
135 -
136         return 0;
137  }
138  
139 @@ -83,16 +143,6 @@ static int squashfs_fill_super(struct su
140         unsigned short flags;
141         unsigned int fragments;
142         u64 lookup_table_start;
143 -       struct {
144 -               struct nlattr nla;
145 -               int val;
146 -       } params = {
147 -               .nla = {
148 -                       .nla_len        = nla_attr_size(sizeof(int)),
149 -                       .nla_type       = ZLIB_DECOMP_WINDOWBITS,
150 -               },
151 -               .val                    = DEF_WBITS,
152 -       };
153         int err;
154  
155         TRACE("Entered squashfs_fill_superblock\n");
156 @@ -104,21 +154,6 @@ static int squashfs_fill_super(struct su
157         }
158         msblk = sb->s_fs_info;
159  
160 -       msblk->tfm = crypto_alloc_pcomp(SQUASHFS_CRYPTO_ALG, 0,
161 -                                       CRYPTO_ALG_ASYNC);
162 -       if (IS_ERR(msblk->tfm)) {
163 -               ERROR("Failed to load %s crypto module\n",
164 -                     SQUASHFS_CRYPTO_ALG);
165 -               err = PTR_ERR(msblk->tfm);
166 -               goto failed_pcomp;
167 -       }
168 -
169 -       err = crypto_decompress_setup(msblk->tfm, &params, sizeof(params));
170 -       if (err) {
171 -               ERROR("Failed to set up decompression parameters\n");
172 -               goto failure;
173 -       }
174 -
175         sblk = kzalloc(sizeof(*sblk), GFP_KERNEL);
176         if (sblk == NULL) {
177                 ERROR("Failed to allocate squashfs_super_block\n");
178 @@ -156,10 +191,28 @@ static int squashfs_fill_super(struct su
179                 goto failed_mount;
180         }
181  
182 +       /* Check block size for sanity */
183 +       msblk->block_size = le32_to_cpu(sblk->block_size);
184 +       if (msblk->block_size > SQUASHFS_FILE_MAX_SIZE)
185 +               goto failed_mount;
186 +
187         /* Check the MAJOR & MINOR versions and compression type */
188         err = supported_squashfs_filesystem(le16_to_cpu(sblk->s_major),
189 -                       le16_to_cpu(sblk->s_minor),
190 -                       le16_to_cpu(sblk->compression));
191 +                       le16_to_cpu(sblk->s_minor));
192 +       if (err < 0)
193 +               goto failed_mount;
194 +
195 +       switch(le16_to_cpu(sblk->compression)) {
196 +       case ZLIB_COMPRESSION:
197 +               err = squashfs_setup_zlib(msblk);
198 +               break;
199 +       case LZMA_COMPRESSION:
200 +               err = squashfs_setup_lzma(msblk);
201 +               break;
202 +       default:
203 +               err = -EINVAL;
204 +               break;
205 +       }
206         if (err < 0)
207                 goto failed_mount;
208  
209 @@ -179,11 +232,6 @@ static int squashfs_fill_super(struct su
210                         i_size_read(sb->s_bdev->bd_inode))
211                 goto failed_mount;
212  
213 -       /* Check block size for sanity */
214 -       msblk->block_size = le32_to_cpu(sblk->block_size);
215 -       if (msblk->block_size > SQUASHFS_FILE_MAX_SIZE)
216 -               goto failed_mount;
217 -
218         /*
219          * Check the system page size is not larger than the filesystem
220          * block size (by default 128K).  This is currently not supported.
221 @@ -315,21 +363,16 @@ allocate_root:
222         return 0;
223  
224  failed_mount:
225 +       if (msblk->tfm)
226 +               crypto_free_pcomp(msblk->tfm);
227         squashfs_cache_delete(msblk->block_cache);
228         squashfs_cache_delete(msblk->fragment_cache);
229         squashfs_cache_delete(msblk->read_page);
230         kfree(msblk->inode_lookup_table);
231         kfree(msblk->fragment_index);
232         kfree(msblk->id_table);
233 -       crypto_free_pcomp(msblk->tfm);
234 -       kfree(sb->s_fs_info);
235 -       sb->s_fs_info = NULL;
236         kfree(sblk);
237 -       return err;
238 -
239  failure:
240 -       crypto_free_pcomp(msblk->tfm);
241 -failed_pcomp:
242         kfree(sb->s_fs_info);
243         sb->s_fs_info = NULL;
244         return err;