Root/
1 | /* |
2 | * misc.c |
3 | * |
4 | * PURPOSE |
5 | * Miscellaneous routines for the OSTA-UDF(tm) filesystem. |
6 | * |
7 | * COPYRIGHT |
8 | * This file is distributed under the terms of the GNU General Public |
9 | * License (GPL). Copies of the GPL can be obtained from: |
10 | * ftp://prep.ai.mit.edu/pub/gnu/GPL |
11 | * Each contributing author retains all rights to their own work. |
12 | * |
13 | * (C) 1998 Dave Boynton |
14 | * (C) 1998-2004 Ben Fennema |
15 | * (C) 1999-2000 Stelias Computing Inc |
16 | * |
17 | * HISTORY |
18 | * |
19 | * 04/19/99 blf partial support for reading/writing specific EA's |
20 | */ |
21 | |
22 | #include "udfdecl.h" |
23 | |
24 | #include <linux/fs.h> |
25 | #include <linux/string.h> |
26 | #include <linux/buffer_head.h> |
27 | #include <linux/crc-itu-t.h> |
28 | |
29 | #include "udf_i.h" |
30 | #include "udf_sb.h" |
31 | |
32 | struct buffer_head *udf_tgetblk(struct super_block *sb, int block) |
33 | { |
34 | if (UDF_QUERY_FLAG(sb, UDF_FLAG_VARCONV)) |
35 | return sb_getblk(sb, udf_fixed_to_variable(block)); |
36 | else |
37 | return sb_getblk(sb, block); |
38 | } |
39 | |
40 | struct buffer_head *udf_tread(struct super_block *sb, int block) |
41 | { |
42 | if (UDF_QUERY_FLAG(sb, UDF_FLAG_VARCONV)) |
43 | return sb_bread(sb, udf_fixed_to_variable(block)); |
44 | else |
45 | return sb_bread(sb, block); |
46 | } |
47 | |
48 | struct genericFormat *udf_add_extendedattr(struct inode *inode, uint32_t size, |
49 | uint32_t type, uint8_t loc) |
50 | { |
51 | uint8_t *ea = NULL, *ad = NULL; |
52 | int offset; |
53 | uint16_t crclen; |
54 | struct udf_inode_info *iinfo = UDF_I(inode); |
55 | |
56 | ea = iinfo->i_ext.i_data; |
57 | if (iinfo->i_lenEAttr) { |
58 | ad = iinfo->i_ext.i_data + iinfo->i_lenEAttr; |
59 | } else { |
60 | ad = ea; |
61 | size += sizeof(struct extendedAttrHeaderDesc); |
62 | } |
63 | |
64 | offset = inode->i_sb->s_blocksize - udf_file_entry_alloc_offset(inode) - |
65 | iinfo->i_lenAlloc; |
66 | |
67 | /* TODO - Check for FreeEASpace */ |
68 | |
69 | if (loc & 0x01 && offset >= size) { |
70 | struct extendedAttrHeaderDesc *eahd; |
71 | eahd = (struct extendedAttrHeaderDesc *)ea; |
72 | |
73 | if (iinfo->i_lenAlloc) |
74 | memmove(&ad[size], ad, iinfo->i_lenAlloc); |
75 | |
76 | if (iinfo->i_lenEAttr) { |
77 | /* check checksum/crc */ |
78 | if (eahd->descTag.tagIdent != |
79 | cpu_to_le16(TAG_IDENT_EAHD) || |
80 | le32_to_cpu(eahd->descTag.tagLocation) != |
81 | iinfo->i_location.logicalBlockNum) |
82 | return NULL; |
83 | } else { |
84 | struct udf_sb_info *sbi = UDF_SB(inode->i_sb); |
85 | |
86 | size -= sizeof(struct extendedAttrHeaderDesc); |
87 | iinfo->i_lenEAttr += |
88 | sizeof(struct extendedAttrHeaderDesc); |
89 | eahd->descTag.tagIdent = cpu_to_le16(TAG_IDENT_EAHD); |
90 | if (sbi->s_udfrev >= 0x0200) |
91 | eahd->descTag.descVersion = cpu_to_le16(3); |
92 | else |
93 | eahd->descTag.descVersion = cpu_to_le16(2); |
94 | eahd->descTag.tagSerialNum = |
95 | cpu_to_le16(sbi->s_serial_number); |
96 | eahd->descTag.tagLocation = cpu_to_le32( |
97 | iinfo->i_location.logicalBlockNum); |
98 | eahd->impAttrLocation = cpu_to_le32(0xFFFFFFFF); |
99 | eahd->appAttrLocation = cpu_to_le32(0xFFFFFFFF); |
100 | } |
101 | |
102 | offset = iinfo->i_lenEAttr; |
103 | if (type < 2048) { |
104 | if (le32_to_cpu(eahd->appAttrLocation) < |
105 | iinfo->i_lenEAttr) { |
106 | uint32_t aal = |
107 | le32_to_cpu(eahd->appAttrLocation); |
108 | memmove(&ea[offset - aal + size], |
109 | &ea[aal], offset - aal); |
110 | offset -= aal; |
111 | eahd->appAttrLocation = |
112 | cpu_to_le32(aal + size); |
113 | } |
114 | if (le32_to_cpu(eahd->impAttrLocation) < |
115 | iinfo->i_lenEAttr) { |
116 | uint32_t ial = |
117 | le32_to_cpu(eahd->impAttrLocation); |
118 | memmove(&ea[offset - ial + size], |
119 | &ea[ial], offset - ial); |
120 | offset -= ial; |
121 | eahd->impAttrLocation = |
122 | cpu_to_le32(ial + size); |
123 | } |
124 | } else if (type < 65536) { |
125 | if (le32_to_cpu(eahd->appAttrLocation) < |
126 | iinfo->i_lenEAttr) { |
127 | uint32_t aal = |
128 | le32_to_cpu(eahd->appAttrLocation); |
129 | memmove(&ea[offset - aal + size], |
130 | &ea[aal], offset - aal); |
131 | offset -= aal; |
132 | eahd->appAttrLocation = |
133 | cpu_to_le32(aal + size); |
134 | } |
135 | } |
136 | /* rewrite CRC + checksum of eahd */ |
137 | crclen = sizeof(struct extendedAttrHeaderDesc) - sizeof(struct tag); |
138 | eahd->descTag.descCRCLength = cpu_to_le16(crclen); |
139 | eahd->descTag.descCRC = cpu_to_le16(crc_itu_t(0, (char *)eahd + |
140 | sizeof(struct tag), crclen)); |
141 | eahd->descTag.tagChecksum = udf_tag_checksum(&eahd->descTag); |
142 | iinfo->i_lenEAttr += size; |
143 | return (struct genericFormat *)&ea[offset]; |
144 | } |
145 | if (loc & 0x02) |
146 | ; |
147 | |
148 | return NULL; |
149 | } |
150 | |
151 | struct genericFormat *udf_get_extendedattr(struct inode *inode, uint32_t type, |
152 | uint8_t subtype) |
153 | { |
154 | struct genericFormat *gaf; |
155 | uint8_t *ea = NULL; |
156 | uint32_t offset; |
157 | struct udf_inode_info *iinfo = UDF_I(inode); |
158 | |
159 | ea = iinfo->i_ext.i_data; |
160 | |
161 | if (iinfo->i_lenEAttr) { |
162 | struct extendedAttrHeaderDesc *eahd; |
163 | eahd = (struct extendedAttrHeaderDesc *)ea; |
164 | |
165 | /* check checksum/crc */ |
166 | if (eahd->descTag.tagIdent != |
167 | cpu_to_le16(TAG_IDENT_EAHD) || |
168 | le32_to_cpu(eahd->descTag.tagLocation) != |
169 | iinfo->i_location.logicalBlockNum) |
170 | return NULL; |
171 | |
172 | if (type < 2048) |
173 | offset = sizeof(struct extendedAttrHeaderDesc); |
174 | else if (type < 65536) |
175 | offset = le32_to_cpu(eahd->impAttrLocation); |
176 | else |
177 | offset = le32_to_cpu(eahd->appAttrLocation); |
178 | |
179 | while (offset < iinfo->i_lenEAttr) { |
180 | gaf = (struct genericFormat *)&ea[offset]; |
181 | if (le32_to_cpu(gaf->attrType) == type && |
182 | gaf->attrSubtype == subtype) |
183 | return gaf; |
184 | else |
185 | offset += le32_to_cpu(gaf->attrLength); |
186 | } |
187 | } |
188 | |
189 | return NULL; |
190 | } |
191 | |
192 | /* |
193 | * udf_read_tagged |
194 | * |
195 | * PURPOSE |
196 | * Read the first block of a tagged descriptor. |
197 | * |
198 | * HISTORY |
199 | * July 1, 1997 - Andrew E. Mileski |
200 | * Written, tested, and released. |
201 | */ |
202 | struct buffer_head *udf_read_tagged(struct super_block *sb, uint32_t block, |
203 | uint32_t location, uint16_t *ident) |
204 | { |
205 | struct tag *tag_p; |
206 | struct buffer_head *bh = NULL; |
207 | |
208 | /* Read the block */ |
209 | if (block == 0xFFFFFFFF) |
210 | return NULL; |
211 | |
212 | bh = udf_tread(sb, block); |
213 | if (!bh) { |
214 | udf_debug("block=%d, location=%d: read failed\n", |
215 | block, location); |
216 | return NULL; |
217 | } |
218 | |
219 | tag_p = (struct tag *)(bh->b_data); |
220 | |
221 | *ident = le16_to_cpu(tag_p->tagIdent); |
222 | |
223 | if (location != le32_to_cpu(tag_p->tagLocation)) { |
224 | udf_debug("location mismatch block %u, tag %u != %u\n", |
225 | block, le32_to_cpu(tag_p->tagLocation), location); |
226 | goto error_out; |
227 | } |
228 | |
229 | /* Verify the tag checksum */ |
230 | if (udf_tag_checksum(tag_p) != tag_p->tagChecksum) { |
231 | printk(KERN_ERR "udf: tag checksum failed block %d\n", block); |
232 | goto error_out; |
233 | } |
234 | |
235 | /* Verify the tag version */ |
236 | if (tag_p->descVersion != cpu_to_le16(0x0002U) && |
237 | tag_p->descVersion != cpu_to_le16(0x0003U)) { |
238 | udf_debug("tag version 0x%04x != 0x0002 || 0x0003 block %d\n", |
239 | le16_to_cpu(tag_p->descVersion), block); |
240 | goto error_out; |
241 | } |
242 | |
243 | /* Verify the descriptor CRC */ |
244 | if (le16_to_cpu(tag_p->descCRCLength) + sizeof(struct tag) > sb->s_blocksize || |
245 | le16_to_cpu(tag_p->descCRC) == crc_itu_t(0, |
246 | bh->b_data + sizeof(struct tag), |
247 | le16_to_cpu(tag_p->descCRCLength))) |
248 | return bh; |
249 | |
250 | udf_debug("Crc failure block %d: crc = %d, crclen = %d\n", block, |
251 | le16_to_cpu(tag_p->descCRC), le16_to_cpu(tag_p->descCRCLength)); |
252 | |
253 | error_out: |
254 | brelse(bh); |
255 | return NULL; |
256 | } |
257 | |
258 | struct buffer_head *udf_read_ptagged(struct super_block *sb, |
259 | struct kernel_lb_addr *loc, |
260 | uint32_t offset, uint16_t *ident) |
261 | { |
262 | return udf_read_tagged(sb, udf_get_lb_pblock(sb, loc, offset), |
263 | loc->logicalBlockNum + offset, ident); |
264 | } |
265 | |
266 | void udf_update_tag(char *data, int length) |
267 | { |
268 | struct tag *tptr = (struct tag *)data; |
269 | length -= sizeof(struct tag); |
270 | |
271 | tptr->descCRCLength = cpu_to_le16(length); |
272 | tptr->descCRC = cpu_to_le16(crc_itu_t(0, data + sizeof(struct tag), length)); |
273 | tptr->tagChecksum = udf_tag_checksum(tptr); |
274 | } |
275 | |
276 | void udf_new_tag(char *data, uint16_t ident, uint16_t version, uint16_t snum, |
277 | uint32_t loc, int length) |
278 | { |
279 | struct tag *tptr = (struct tag *)data; |
280 | tptr->tagIdent = cpu_to_le16(ident); |
281 | tptr->descVersion = cpu_to_le16(version); |
282 | tptr->tagSerialNum = cpu_to_le16(snum); |
283 | tptr->tagLocation = cpu_to_le32(loc); |
284 | udf_update_tag(data, length); |
285 | } |
286 | |
287 | u8 udf_tag_checksum(const struct tag *t) |
288 | { |
289 | u8 *data = (u8 *)t; |
290 | u8 checksum = 0; |
291 | int i; |
292 | for (i = 0; i < sizeof(struct tag); ++i) |
293 | if (i != 4) /* position of checksum */ |
294 | checksum += data[i]; |
295 | return checksum; |
296 | } |
297 |
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