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;
56 ea = UDF_I_DATA(inode);
57 if (UDF_I_LENEATTR(inode))
58 ad = UDF_I_DATA(inode) + UDF_I_LENEATTR(inode);
61 size += sizeof(struct extendedAttrHeaderDesc);
64 offset = inode->i_sb->s_blocksize - udf_file_entry_alloc_offset(inode) -
65 UDF_I_LENALLOC(inode);
67 /* TODO - Check for FreeEASpace */
69 if (loc & 0x01 && offset >= size) {
70 struct extendedAttrHeaderDesc *eahd;
71 eahd = (struct extendedAttrHeaderDesc *)ea;
73 if (UDF_I_LENALLOC(inode)) {
74 memmove(&ad[size], ad, UDF_I_LENALLOC(inode));
77 if (UDF_I_LENEATTR(inode)) {
78 /* check checksum/crc */
79 if (le16_to_cpu(eahd->descTag.tagIdent) !=
81 || le32_to_cpu(eahd->descTag.tagLocation) !=
82 UDF_I_LOCATION(inode).logicalBlockNum) {
86 size -= sizeof(struct extendedAttrHeaderDesc);
87 UDF_I_LENEATTR(inode) +=
88 sizeof(struct extendedAttrHeaderDesc);
89 eahd->descTag.tagIdent = cpu_to_le16(TAG_IDENT_EAHD);
90 if (UDF_SB_UDFREV(inode->i_sb) >= 0x0200)
91 eahd->descTag.descVersion = cpu_to_le16(3);
93 eahd->descTag.descVersion = cpu_to_le16(2);
94 eahd->descTag.tagSerialNum =
95 cpu_to_le16(UDF_SB_SERIALNUM(inode->i_sb));
96 eahd->descTag.tagLocation =
97 cpu_to_le32(UDF_I_LOCATION(inode).logicalBlockNum);
98 eahd->impAttrLocation = cpu_to_le32(0xFFFFFFFF);
99 eahd->appAttrLocation = cpu_to_le32(0xFFFFFFFF);
102 offset = UDF_I_LENEATTR(inode);
104 if (le32_to_cpu(eahd->appAttrLocation) <
105 UDF_I_LENEATTR(inode)) {
107 le32_to_cpu(eahd->appAttrLocation);
108 memmove(&ea[offset - aal + size], &ea[aal],
111 eahd->appAttrLocation = 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], &ea[ial],
120 eahd->impAttrLocation = cpu_to_le32(ial + size);
122 } else if (type < 65536) {
123 if (le32_to_cpu(eahd->appAttrLocation) <
124 UDF_I_LENEATTR(inode)) {
126 le32_to_cpu(eahd->appAttrLocation);
127 memmove(&ea[offset - aal + size], &ea[aal],
130 eahd->appAttrLocation = cpu_to_le32(aal + size);
133 /* rewrite CRC + checksum of eahd */
134 crclen = sizeof(struct extendedAttrHeaderDesc) - sizeof(tag);
135 eahd->descTag.descCRCLength = cpu_to_le16(crclen);
136 eahd->descTag.descCRC =
137 cpu_to_le16(udf_crc((char *)eahd + sizeof(tag), crclen, 0));
138 eahd->descTag.tagChecksum = 0;
139 for (i = 0; i < 16; i++)
141 eahd->descTag.tagChecksum +=
142 ((uint8_t *) & (eahd->descTag))[i];
143 UDF_I_LENEATTR(inode) += size;
144 return (struct genericFormat *)&ea[offset];
151 struct genericFormat *udf_get_extendedattr(struct inode *inode, uint32_t type,
154 struct genericFormat *gaf;
158 ea = UDF_I_DATA(inode);
160 if (UDF_I_LENEATTR(inode)) {
161 struct extendedAttrHeaderDesc *eahd;
162 eahd = (struct extendedAttrHeaderDesc *)ea;
164 /* check checksum/crc */
165 if (le16_to_cpu(eahd->descTag.tagIdent) != TAG_IDENT_EAHD ||
166 le32_to_cpu(eahd->descTag.tagLocation) !=
167 UDF_I_LOCATION(inode).logicalBlockNum) {
172 offset = sizeof(struct extendedAttrHeaderDesc);
173 else if (type < 65536)
174 offset = le32_to_cpu(eahd->impAttrLocation);
176 offset = le32_to_cpu(eahd->appAttrLocation);
178 while (offset < UDF_I_LENEATTR(inode)) {
179 gaf = (struct genericFormat *)&ea[offset];
180 if (le32_to_cpu(gaf->attrType) == type
181 && gaf->attrSubtype == subtype)
184 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 register uint8_t checksum;
209 if (block == 0xFFFFFFFF)
212 bh = udf_tread(sb, block + UDF_SB_SESSION(sb));
214 udf_debug("block=%d, location=%d: read failed\n",
215 block + UDF_SB_SESSION(sb), location);
219 tag_p = (tag *) (bh->b_data);
221 *ident = le16_to_cpu(tag_p->tagIdent);
223 if (location != le32_to_cpu(tag_p->tagLocation)) {
224 udf_debug("location mismatch block %u, tag %u != %u\n",
225 block + UDF_SB_SESSION(sb),
226 le32_to_cpu(tag_p->tagLocation), location);
230 /* Verify the tag checksum */
232 for (i = 0; i < 4; i++)
233 checksum += (uint8_t) (bh->b_data[i]);
234 for (i = 5; i < 16; i++)
235 checksum += (uint8_t) (bh->b_data[i]);
236 if (checksum != tag_p->tagChecksum) {
237 printk(KERN_ERR "udf: tag checksum failed block %d\n", block);
241 /* Verify the tag version */
242 if (le16_to_cpu(tag_p->descVersion) != 0x0002U &&
243 le16_to_cpu(tag_p->descVersion) != 0x0003U) {
244 udf_debug("tag version 0x%04x != 0x0002 || 0x0003 block %d\n",
245 le16_to_cpu(tag_p->descVersion), block);
249 /* Verify the descriptor CRC */
250 if (le16_to_cpu(tag_p->descCRCLength) + sizeof(tag) > sb->s_blocksize ||
251 le16_to_cpu(tag_p->descCRC) == udf_crc(bh->b_data + sizeof(tag),
257 udf_debug("Crc failure block %d: crc = %d, crclen = %d\n",
258 block + UDF_SB_SESSION(sb), le16_to_cpu(tag_p->descCRC),
259 le16_to_cpu(tag_p->descCRCLength));
266 struct buffer_head *udf_read_ptagged(struct super_block *sb, kernel_lb_addr loc,
267 uint32_t offset, uint16_t * ident)
269 return udf_read_tagged(sb, udf_get_lb_pblock(sb, loc, offset),
270 loc.logicalBlockNum + offset, ident);
273 void udf_update_tag(char *data, int length)
275 tag *tptr = (tag *) data;
278 length -= sizeof(tag);
280 tptr->tagChecksum = 0;
281 tptr->descCRCLength = cpu_to_le16(length);
282 tptr->descCRC = cpu_to_le16(udf_crc(data + sizeof(tag), length, 0));
284 for (i = 0; i < 16; i++)
286 tptr->tagChecksum += (uint8_t) (data[i]);
289 void udf_new_tag(char *data, uint16_t ident, uint16_t version, uint16_t snum,
290 uint32_t loc, int length)
292 tag *tptr = (tag *) data;
293 tptr->tagIdent = cpu_to_le16(ident);
294 tptr->descVersion = cpu_to_le16(version);
295 tptr->tagSerialNum = cpu_to_le16(snum);
296 tptr->tagLocation = cpu_to_le32(loc);
297 udf_update_tag(data, length);