1 /* 2 * directory.c 3 * 4 * PURPOSE 5 * Directory related functions 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 14 #include "udfdecl.h" 15 #include "udf_i.h" 16 17 #include <linux/fs.h> 18 #include <linux/string.h> 19 20 struct fileIdentDesc *udf_fileident_read(struct inode *dir, loff_t *nf_pos, 21 struct udf_fileident_bh *fibh, 22 struct fileIdentDesc *cfi, 23 struct extent_position *epos, 24 struct kernel_lb_addr *eloc, uint32_t *elen, 25 sector_t *offset) 26 { 27 struct fileIdentDesc *fi; 28 int i, num, block; 29 struct buffer_head *tmp, *bha[16]; 30 struct udf_inode_info *iinfo = UDF_I(dir); 31 32 fibh->soffset = fibh->eoffset; 33 34 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) { 35 fi = udf_get_fileident(iinfo->i_ext.i_data - 36 (iinfo->i_efe ? 37 sizeof(struct extendedFileEntry) : 38 sizeof(struct fileEntry)), 39 dir->i_sb->s_blocksize, 40 &(fibh->eoffset)); 41 if (!fi) 42 return NULL; 43 44 *nf_pos += fibh->eoffset - fibh->soffset; 45 46 memcpy((uint8_t *)cfi, (uint8_t *)fi, 47 sizeof(struct fileIdentDesc)); 48 49 return fi; 50 } 51 52 if (fibh->eoffset == dir->i_sb->s_blocksize) { 53 int lextoffset = epos->offset; 54 unsigned char blocksize_bits = dir->i_sb->s_blocksize_bits; 55 56 if (udf_next_aext(dir, epos, eloc, elen, 1) != 57 (EXT_RECORDED_ALLOCATED >> 30)) 58 return NULL; 59 60 block = udf_get_lb_pblock(dir->i_sb, eloc, *offset); 61 62 (*offset)++; 63 64 if ((*offset << blocksize_bits) >= *elen) 65 *offset = 0; 66 else 67 epos->offset = lextoffset; 68 69 brelse(fibh->sbh); 70 fibh->sbh = fibh->ebh = udf_tread(dir->i_sb, block); 71 if (!fibh->sbh) 72 return NULL; 73 fibh->soffset = fibh->eoffset = 0; 74 75 if (!(*offset & ((16 >> (blocksize_bits - 9)) - 1))) { 76 i = 16 >> (blocksize_bits - 9); 77 if (i + *offset > (*elen >> blocksize_bits)) 78 i = (*elen >> blocksize_bits)-*offset; 79 for (num = 0; i > 0; i--) { 80 block = udf_get_lb_pblock(dir->i_sb, eloc, 81 *offset + i); 82 tmp = udf_tgetblk(dir->i_sb, block); 83 if (tmp && !buffer_uptodate(tmp) && 84 !buffer_locked(tmp)) 85 bha[num++] = tmp; 86 else 87 brelse(tmp); 88 } 89 if (num) { 90 ll_rw_block(READA, num, bha); 91 for (i = 0; i < num; i++) 92 brelse(bha[i]); 93 } 94 } 95 } else if (fibh->sbh != fibh->ebh) { 96 brelse(fibh->sbh); 97 fibh->sbh = fibh->ebh; 98 } 99 100 fi = udf_get_fileident(fibh->sbh->b_data, dir->i_sb->s_blocksize, 101 &(fibh->eoffset)); 102 103 if (!fi) 104 return NULL; 105 106 *nf_pos += fibh->eoffset - fibh->soffset; 107 108 if (fibh->eoffset <= dir->i_sb->s_blocksize) { 109 memcpy((uint8_t *)cfi, (uint8_t *)fi, 110 sizeof(struct fileIdentDesc)); 111 } else if (fibh->eoffset > dir->i_sb->s_blocksize) { 112 int lextoffset = epos->offset; 113 114 if (udf_next_aext(dir, epos, eloc, elen, 1) != 115 (EXT_RECORDED_ALLOCATED >> 30)) 116 return NULL; 117 118 block = udf_get_lb_pblock(dir->i_sb, eloc, *offset); 119 120 (*offset)++; 121 122 if ((*offset << dir->i_sb->s_blocksize_bits) >= *elen) 123 *offset = 0; 124 else 125 epos->offset = lextoffset; 126 127 fibh->soffset -= dir->i_sb->s_blocksize; 128 fibh->eoffset -= dir->i_sb->s_blocksize; 129 130 fibh->ebh = udf_tread(dir->i_sb, block); 131 if (!fibh->ebh) 132 return NULL; 133 134 if (sizeof(struct fileIdentDesc) > -fibh->soffset) { 135 int fi_len; 136 137 memcpy((uint8_t *)cfi, (uint8_t *)fi, -fibh->soffset); 138 memcpy((uint8_t *)cfi - fibh->soffset, 139 fibh->ebh->b_data, 140 sizeof(struct fileIdentDesc) + fibh->soffset); 141 142 fi_len = (sizeof(struct fileIdentDesc) + 143 cfi->lengthFileIdent + 144 le16_to_cpu(cfi->lengthOfImpUse) + 3) & ~3; 145 146 *nf_pos += fi_len - (fibh->eoffset - fibh->soffset); 147 fibh->eoffset = fibh->soffset + fi_len; 148 } else { 149 memcpy((uint8_t *)cfi, (uint8_t *)fi, 150 sizeof(struct fileIdentDesc)); 151 } 152 } 153 return fi; 154 } 155 156 struct fileIdentDesc *udf_get_fileident(void *buffer, int bufsize, int *offset) 157 { 158 struct fileIdentDesc *fi; 159 int lengthThisIdent; 160 uint8_t *ptr; 161 int padlen; 162 163 if ((!buffer) || (!offset)) { 164 udf_debug("invalidparms, buffer=%p, offset=%p\n", 165 buffer, offset); 166 return NULL; 167 } 168 169 ptr = buffer; 170 171 if ((*offset > 0) && (*offset < bufsize)) 172 ptr += *offset; 173 fi = (struct fileIdentDesc *)ptr; 174 if (fi->descTag.tagIdent != cpu_to_le16(TAG_IDENT_FID)) { 175 udf_debug("0x%x != TAG_IDENT_FID\n", 176 le16_to_cpu(fi->descTag.tagIdent)); 177 udf_debug("offset: %u sizeof: %lu bufsize: %u\n", 178 *offset, (unsigned long)sizeof(struct fileIdentDesc), 179 bufsize); 180 return NULL; 181 } 182 if ((*offset + sizeof(struct fileIdentDesc)) > bufsize) 183 lengthThisIdent = sizeof(struct fileIdentDesc); 184 else 185 lengthThisIdent = sizeof(struct fileIdentDesc) + 186 fi->lengthFileIdent + le16_to_cpu(fi->lengthOfImpUse); 187 188 /* we need to figure padding, too! */ 189 padlen = lengthThisIdent % UDF_NAME_PAD; 190 if (padlen) 191 lengthThisIdent += (UDF_NAME_PAD - padlen); 192 *offset = *offset + lengthThisIdent; 193 194 return fi; 195 } 196 197 struct short_ad *udf_get_fileshortad(uint8_t *ptr, int maxoffset, uint32_t *offset, 198 int inc) 199 { 200 struct short_ad *sa; 201 202 if ((!ptr) || (!offset)) { 203 pr_err("%s: invalidparms\n", __func__); 204 return NULL; 205 } 206 207 if ((*offset + sizeof(struct short_ad)) > maxoffset) 208 return NULL; 209 else { 210 sa = (struct short_ad *)ptr; 211 if (sa->extLength == 0) 212 return NULL; 213 } 214 215 if (inc) 216 *offset += sizeof(struct short_ad); 217 return sa; 218 } 219 220 struct long_ad *udf_get_filelongad(uint8_t *ptr, int maxoffset, uint32_t *offset, int inc) 221 { 222 struct long_ad *la; 223 224 if ((!ptr) || (!offset)) { 225 pr_err("%s: invalidparms\n", __func__); 226 return NULL; 227 } 228 229 if ((*offset + sizeof(struct long_ad)) > maxoffset) 230 return NULL; 231 else { 232 la = (struct long_ad *)ptr; 233 if (la->extLength == 0) 234 return NULL; 235 } 236 237 if (inc) 238 *offset += sizeof(struct long_ad); 239 return la; 240 } 241