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5 * Miscellaneous routines for the OSTA-UDF(tm) filesystem.
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.
13 * (C) 1998 Dave Boynton
14 * (C) 1998-2004 Ben Fennema
15 * (C) 1999-2000 Stelias Computing Inc
19 * 04/19/99 blf partial support for reading/writing specific EA's
25 #include <linux/string.h>
26 #include <linux/crc-itu-t.h>
31 struct buffer_head
*udf_tgetblk(struct super_block
*sb
, int block
)
33 if (UDF_QUERY_FLAG(sb
, UDF_FLAG_VARCONV
))
34 return sb_getblk(sb
, udf_fixed_to_variable(block
));
36 return sb_getblk(sb
, block
);
39 struct buffer_head
*udf_tread(struct super_block
*sb
, int block
)
41 if (UDF_QUERY_FLAG(sb
, UDF_FLAG_VARCONV
))
42 return sb_bread(sb
, udf_fixed_to_variable(block
));
44 return sb_bread(sb
, block
);
47 struct genericFormat
*udf_add_extendedattr(struct inode
*inode
, uint32_t size
,
48 uint32_t type
, uint8_t loc
)
50 uint8_t *ea
= NULL
, *ad
= NULL
;
53 struct udf_inode_info
*iinfo
= UDF_I(inode
);
55 ea
= iinfo
->i_ext
.i_data
;
56 if (iinfo
->i_lenEAttr
) {
57 ad
= iinfo
->i_ext
.i_data
+ iinfo
->i_lenEAttr
;
60 size
+= sizeof(struct extendedAttrHeaderDesc
);
63 offset
= inode
->i_sb
->s_blocksize
- udf_file_entry_alloc_offset(inode
) -
66 /* TODO - Check for FreeEASpace */
68 if (loc
& 0x01 && offset
>= size
) {
69 struct extendedAttrHeaderDesc
*eahd
;
70 eahd
= (struct extendedAttrHeaderDesc
*)ea
;
72 if (iinfo
->i_lenAlloc
)
73 memmove(&ad
[size
], ad
, iinfo
->i_lenAlloc
);
75 if (iinfo
->i_lenEAttr
) {
76 /* check checksum/crc */
77 if (eahd
->descTag
.tagIdent
!=
78 cpu_to_le16(TAG_IDENT_EAHD
) ||
79 le32_to_cpu(eahd
->descTag
.tagLocation
) !=
80 iinfo
->i_location
.logicalBlockNum
)
83 struct udf_sb_info
*sbi
= UDF_SB(inode
->i_sb
);
85 size
-= sizeof(struct extendedAttrHeaderDesc
);
87 sizeof(struct extendedAttrHeaderDesc
);
88 eahd
->descTag
.tagIdent
= cpu_to_le16(TAG_IDENT_EAHD
);
89 if (sbi
->s_udfrev
>= 0x0200)
90 eahd
->descTag
.descVersion
= cpu_to_le16(3);
92 eahd
->descTag
.descVersion
= cpu_to_le16(2);
93 eahd
->descTag
.tagSerialNum
=
94 cpu_to_le16(sbi
->s_serial_number
);
95 eahd
->descTag
.tagLocation
= cpu_to_le32(
96 iinfo
->i_location
.logicalBlockNum
);
97 eahd
->impAttrLocation
= cpu_to_le32(0xFFFFFFFF);
98 eahd
->appAttrLocation
= cpu_to_le32(0xFFFFFFFF);
101 offset
= iinfo
->i_lenEAttr
;
103 if (le32_to_cpu(eahd
->appAttrLocation
) <
106 le32_to_cpu(eahd
->appAttrLocation
);
109 memmove(&ea
[offset
- aal
+ size
],
110 &ea
[aal
], offset
- aal
);
112 eahd
->appAttrLocation
=
113 cpu_to_le32(aal
+ size
);
115 if (le32_to_cpu(eahd
->impAttrLocation
) <
118 le32_to_cpu(eahd
->impAttrLocation
);
121 memmove(&ea
[offset
- ial
+ size
],
122 &ea
[ial
], offset
- ial
);
124 eahd
->impAttrLocation
=
125 cpu_to_le32(ial
+ size
);
127 } else if (type
< 65536) {
128 if (le32_to_cpu(eahd
->appAttrLocation
) <
131 le32_to_cpu(eahd
->appAttrLocation
);
134 memmove(&ea
[offset
- aal
+ size
],
135 &ea
[aal
], offset
- aal
);
137 eahd
->appAttrLocation
=
138 cpu_to_le32(aal
+ size
);
141 /* rewrite CRC + checksum of eahd */
142 crclen
= sizeof(struct extendedAttrHeaderDesc
) - sizeof(struct tag
);
143 eahd
->descTag
.descCRCLength
= cpu_to_le16(crclen
);
144 eahd
->descTag
.descCRC
= cpu_to_le16(crc_itu_t(0, (char *)eahd
+
145 sizeof(struct tag
), crclen
));
146 eahd
->descTag
.tagChecksum
= udf_tag_checksum(&eahd
->descTag
);
147 iinfo
->i_lenEAttr
+= size
;
148 return (struct genericFormat
*)&ea
[offset
];
154 struct genericFormat
*udf_get_extendedattr(struct inode
*inode
, uint32_t type
,
157 struct genericFormat
*gaf
;
160 struct udf_inode_info
*iinfo
= UDF_I(inode
);
162 ea
= iinfo
->i_ext
.i_data
;
164 if (iinfo
->i_lenEAttr
) {
165 struct extendedAttrHeaderDesc
*eahd
;
166 eahd
= (struct extendedAttrHeaderDesc
*)ea
;
168 /* check checksum/crc */
169 if (eahd
->descTag
.tagIdent
!=
170 cpu_to_le16(TAG_IDENT_EAHD
) ||
171 le32_to_cpu(eahd
->descTag
.tagLocation
) !=
172 iinfo
->i_location
.logicalBlockNum
)
176 offset
= sizeof(struct extendedAttrHeaderDesc
);
177 else if (type
< 65536)
178 offset
= le32_to_cpu(eahd
->impAttrLocation
);
180 offset
= le32_to_cpu(eahd
->appAttrLocation
);
182 while (offset
< iinfo
->i_lenEAttr
) {
183 gaf
= (struct genericFormat
*)&ea
[offset
];
184 if (le32_to_cpu(gaf
->attrType
) == type
&&
185 gaf
->attrSubtype
== subtype
)
188 offset
+= le32_to_cpu(gaf
->attrLength
);
199 * Read the first block of a tagged descriptor.
202 * July 1, 1997 - Andrew E. Mileski
203 * Written, tested, and released.
205 struct buffer_head
*udf_read_tagged(struct super_block
*sb
, uint32_t block
,
206 uint32_t location
, uint16_t *ident
)
209 struct buffer_head
*bh
= NULL
;
213 if (block
== 0xFFFFFFFF)
216 bh
= udf_tread(sb
, block
);
218 udf_err(sb
, "read failed, block=%u, location=%d\n",
223 tag_p
= (struct tag
*)(bh
->b_data
);
225 *ident
= le16_to_cpu(tag_p
->tagIdent
);
227 if (location
!= le32_to_cpu(tag_p
->tagLocation
)) {
228 udf_debug("location mismatch block %u, tag %u != %u\n",
229 block
, le32_to_cpu(tag_p
->tagLocation
), location
);
233 /* Verify the tag checksum */
234 checksum
= udf_tag_checksum(tag_p
);
235 if (checksum
!= tag_p
->tagChecksum
) {
236 udf_err(sb
, "tag checksum failed, block %u: 0x%02x != 0x%02x\n",
237 block
, checksum
, tag_p
->tagChecksum
);
241 /* Verify the tag version */
242 if (tag_p
->descVersion
!= cpu_to_le16(0x0002U
) &&
243 tag_p
->descVersion
!= cpu_to_le16(0x0003U
)) {
244 udf_err(sb
, "tag version 0x%04x != 0x0002 || 0x0003, block %u\n",
245 le16_to_cpu(tag_p
->descVersion
), block
);
249 /* Verify the descriptor CRC */
250 if (le16_to_cpu(tag_p
->descCRCLength
) + sizeof(struct tag
) > sb
->s_blocksize
||
251 le16_to_cpu(tag_p
->descCRC
) == crc_itu_t(0,
252 bh
->b_data
+ sizeof(struct tag
),
253 le16_to_cpu(tag_p
->descCRCLength
)))
256 udf_debug("Crc failure block %d: crc = %d, crclen = %d\n", block
,
257 le16_to_cpu(tag_p
->descCRC
),
258 le16_to_cpu(tag_p
->descCRCLength
));
264 struct buffer_head
*udf_read_ptagged(struct super_block
*sb
,
265 struct kernel_lb_addr
*loc
,
266 uint32_t offset
, uint16_t *ident
)
268 return udf_read_tagged(sb
, udf_get_lb_pblock(sb
, loc
, offset
),
269 loc
->logicalBlockNum
+ offset
, ident
);
272 void udf_update_tag(char *data
, int length
)
274 struct tag
*tptr
= (struct tag
*)data
;
275 length
-= sizeof(struct tag
);
277 tptr
->descCRCLength
= cpu_to_le16(length
);
278 tptr
->descCRC
= cpu_to_le16(crc_itu_t(0, data
+ sizeof(struct tag
), length
));
279 tptr
->tagChecksum
= udf_tag_checksum(tptr
);
282 void udf_new_tag(char *data
, uint16_t ident
, uint16_t version
, uint16_t snum
,
283 uint32_t loc
, int length
)
285 struct tag
*tptr
= (struct tag
*)data
;
286 tptr
->tagIdent
= cpu_to_le16(ident
);
287 tptr
->descVersion
= cpu_to_le16(version
);
288 tptr
->tagSerialNum
= cpu_to_le16(snum
);
289 tptr
->tagLocation
= cpu_to_le32(loc
);
290 udf_update_tag(data
, length
);
293 u8
udf_tag_checksum(const struct tag
*t
)
298 for (i
= 0; i
< sizeof(struct tag
); ++i
)
299 if (i
!= 4) /* position of checksum */