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/udf_fs.h>
27 #include <linux/buffer_head.h>
32 struct buffer_head *udf_tgetblk(struct super_block *sb, int block)
34 if (UDF_QUERY_FLAG(sb, UDF_FLAG_VARCONV))
35 return sb_getblk(sb, udf_fixed_to_variable(block));
37 return sb_getblk(sb, block);
40 struct buffer_head *udf_tread(struct super_block *sb, int block)
42 if (UDF_QUERY_FLAG(sb, UDF_FLAG_VARCONV))
43 return sb_bread(sb, udf_fixed_to_variable(block));
45 return sb_bread(sb, block);
48 struct genericFormat *udf_add_extendedattr(struct inode *inode, uint32_t size,
49 uint32_t type, uint8_t loc)
51 uint8_t *ea = NULL, *ad = NULL;
55 ea = UDF_I_DATA(inode);
56 if (UDF_I_LENEATTR(inode)) {
57 ad = UDF_I_DATA(inode) + UDF_I_LENEATTR(inode);
60 size += sizeof(struct extendedAttrHeaderDesc);
63 offset = inode->i_sb->s_blocksize - udf_file_entry_alloc_offset(inode) -
64 UDF_I_LENALLOC(inode);
66 /* TODO - Check for FreeEASpace */
68 if (loc & 0x01 && offset >= size) {
69 struct extendedAttrHeaderDesc *eahd;
70 eahd = (struct extendedAttrHeaderDesc *)ea;
72 if (UDF_I_LENALLOC(inode))
73 memmove(&ad[size], ad, UDF_I_LENALLOC(inode));
75 if (UDF_I_LENEATTR(inode)) {
76 /* check checksum/crc */
77 if (le16_to_cpu(eahd->descTag.tagIdent) !=
79 le32_to_cpu(eahd->descTag.tagLocation) !=
80 UDF_I_LOCATION(inode).logicalBlockNum)
83 struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
85 size -= sizeof(struct extendedAttrHeaderDesc);
86 UDF_I_LENEATTR(inode) +=
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 UDF_I_LOCATION(inode).logicalBlockNum);
97 eahd->impAttrLocation = cpu_to_le32(0xFFFFFFFF);
98 eahd->appAttrLocation = cpu_to_le32(0xFFFFFFFF);
101 offset = UDF_I_LENEATTR(inode);
103 if (le32_to_cpu(eahd->appAttrLocation) <
104 UDF_I_LENEATTR(inode)) {
106 le32_to_cpu(eahd->appAttrLocation);
107 memmove(&ea[offset - aal + size],
108 &ea[aal], offset - aal);
110 eahd->appAttrLocation =
111 cpu_to_le32(aal + size);
113 if (le32_to_cpu(eahd->impAttrLocation) <
114 UDF_I_LENEATTR(inode)) {
116 le32_to_cpu(eahd->impAttrLocation);
117 memmove(&ea[offset - ial + size],
118 &ea[ial], offset - ial);
120 eahd->impAttrLocation =
121 cpu_to_le32(ial + size);
123 } else if (type < 65536) {
124 if (le32_to_cpu(eahd->appAttrLocation) <
125 UDF_I_LENEATTR(inode)) {
127 le32_to_cpu(eahd->appAttrLocation);
128 memmove(&ea[offset - aal + size],
129 &ea[aal], offset - aal);
131 eahd->appAttrLocation =
132 cpu_to_le32(aal + size);
135 /* rewrite CRC + checksum of eahd */
136 crclen = sizeof(struct extendedAttrHeaderDesc) - sizeof(tag);
137 eahd->descTag.descCRCLength = cpu_to_le16(crclen);
138 eahd->descTag.descCRC = cpu_to_le16(udf_crc((char *)eahd +
139 sizeof(tag), crclen, 0));
140 eahd->descTag.tagChecksum = udf_tag_checksum(&eahd->descTag);
141 UDF_I_LENEATTR(inode) += size;
142 return (struct genericFormat *)&ea[offset];
150 struct genericFormat *udf_get_extendedattr(struct inode *inode, uint32_t type,
153 struct genericFormat *gaf;
157 ea = UDF_I_DATA(inode);
159 if (UDF_I_LENEATTR(inode)) {
160 struct extendedAttrHeaderDesc *eahd;
161 eahd = (struct extendedAttrHeaderDesc *)ea;
163 /* check checksum/crc */
164 if (le16_to_cpu(eahd->descTag.tagIdent) !=
166 le32_to_cpu(eahd->descTag.tagLocation) !=
167 UDF_I_LOCATION(inode).logicalBlockNum)
171 offset = sizeof(struct extendedAttrHeaderDesc);
172 else if (type < 65536)
173 offset = le32_to_cpu(eahd->impAttrLocation);
175 offset = le32_to_cpu(eahd->appAttrLocation);
177 while (offset < UDF_I_LENEATTR(inode)) {
178 gaf = (struct genericFormat *)&ea[offset];
179 if (le32_to_cpu(gaf->attrType) == type &&
180 gaf->attrSubtype == subtype)
183 offset += le32_to_cpu(gaf->attrLength);
194 * Read the first block of a tagged descriptor.
197 * July 1, 1997 - Andrew E. Mileski
198 * Written, tested, and released.
200 struct buffer_head *udf_read_tagged(struct super_block *sb, uint32_t block,
201 uint32_t location, uint16_t *ident)
204 struct buffer_head *bh = NULL;
205 struct udf_sb_info *sbi = UDF_SB(sb);
208 if (block == 0xFFFFFFFF)
211 bh = udf_tread(sb, block + sbi->s_session);
213 udf_debug("block=%d, location=%d: read failed\n",
214 block + sbi->s_session, location);
218 tag_p = (tag *)(bh->b_data);
220 *ident = le16_to_cpu(tag_p->tagIdent);
222 if (location != le32_to_cpu(tag_p->tagLocation)) {
223 udf_debug("location mismatch block %u, tag %u != %u\n",
224 block + sbi->s_session,
225 le32_to_cpu(tag_p->tagLocation), location);
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);
235 /* Verify the tag version */
236 if (le16_to_cpu(tag_p->descVersion) != 0x0002U &&
237 le16_to_cpu(tag_p->descVersion) != 0x0003U) {
238 udf_debug("tag version 0x%04x != 0x0002 || 0x0003 block %d\n",
239 le16_to_cpu(tag_p->descVersion), block);
243 /* Verify the descriptor CRC */
244 if (le16_to_cpu(tag_p->descCRCLength) + sizeof(tag) > sb->s_blocksize ||
245 le16_to_cpu(tag_p->descCRC) == udf_crc(bh->b_data + sizeof(tag),
246 le16_to_cpu(tag_p->descCRCLength), 0))
249 udf_debug("Crc failure block %d: crc = %d, crclen = %d\n",
250 block + sbi->s_session, le16_to_cpu(tag_p->descCRC),
251 le16_to_cpu(tag_p->descCRCLength));
258 struct buffer_head *udf_read_ptagged(struct super_block *sb, kernel_lb_addr loc,
259 uint32_t offset, uint16_t *ident)
261 return udf_read_tagged(sb, udf_get_lb_pblock(sb, loc, offset),
262 loc.logicalBlockNum + offset, ident);
265 void udf_update_tag(char *data, int length)
267 tag *tptr = (tag *)data;
268 length -= sizeof(tag);
270 tptr->descCRCLength = cpu_to_le16(length);
271 tptr->descCRC = cpu_to_le16(udf_crc(data + sizeof(tag), length, 0));
272 tptr->tagChecksum = udf_tag_checksum(tptr);
275 void udf_new_tag(char *data, uint16_t ident, uint16_t version, uint16_t snum,
276 uint32_t loc, int length)
278 tag *tptr = (tag *)data;
279 tptr->tagIdent = cpu_to_le16(ident);
280 tptr->descVersion = cpu_to_le16(version);
281 tptr->tagSerialNum = cpu_to_le16(snum);
282 tptr->tagLocation = cpu_to_le32(loc);
283 udf_update_tag(data, length);
286 u8 udf_tag_checksum(const tag *t)
291 for (i = 0; i < sizeof(tag); ++i)
292 if (i != 4) /* position of checksum */