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#include <linux/buffer_head.h> 20 21struct fileIdentDesc *udf_fileident_read(struct inode *dir, loff_t *nf_pos, 22 struct udf_fileident_bh *fibh, 23 struct fileIdentDesc *cfi, 24 struct extent_position *epos, 25 struct kernel_lb_addr *eloc, uint32_t *elen, 26 sector_t *offset) 27{ 28 struct fileIdentDesc *fi; 29 int i, num, block; 30 struct buffer_head *tmp, *bha[16]; 31 struct udf_inode_info *iinfo = UDF_I(dir); 32 33 fibh->soffset = fibh->eoffset; 34 35 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) { 36 fi = udf_get_fileident(iinfo->i_ext.i_data - 37 (iinfo->i_efe ? 38 sizeof(struct extendedFileEntry) : 39 sizeof(struct fileEntry)), 40 dir->i_sb->s_blocksize, 41 &(fibh->eoffset)); 42 if (!fi) 43 return NULL; 44 45 *nf_pos += fibh->eoffset - fibh->soffset; 46 47 memcpy((uint8_t *)cfi, (uint8_t *)fi, 48 sizeof(struct fileIdentDesc)); 49 50 return fi; 51 } 52 53 if (fibh->eoffset == dir->i_sb->s_blocksize) { 54 int lextoffset = epos->offset; 55 unsigned char blocksize_bits = dir->i_sb->s_blocksize_bits; 56 57 if (udf_next_aext(dir, epos, eloc, elen, 1) != 58 (EXT_RECORDED_ALLOCATED >> 30)) 59 return NULL; 60 61 block = udf_get_lb_pblock(dir->i_sb, eloc, *offset); 62 63 (*offset)++; 64 65 if ((*offset << blocksize_bits) >= *elen) 66 *offset = 0; 67 else 68 epos->offset = lextoffset; 69 70 brelse(fibh->sbh); 71 fibh->sbh = fibh->ebh = udf_tread(dir->i_sb, block); 72 if (!fibh->sbh) 73 return NULL; 74 fibh->soffset = fibh->eoffset = 0; 75 76 if (!(*offset & ((16 >> (blocksize_bits - 9)) - 1))) { 77 i = 16 >> (blocksize_bits - 9); 78 if (i + *offset > (*elen >> blocksize_bits)) 79 i = (*elen >> blocksize_bits)-*offset; 80 for (num = 0; i > 0; i--) { 81 block = udf_get_lb_pblock(dir->i_sb, eloc, 82 *offset + i); 83 tmp = udf_tgetblk(dir->i_sb, block); 84 if (tmp && !buffer_uptodate(tmp) && 85 !buffer_locked(tmp)) 86 bha[num++] = tmp; 87 else 88 brelse(tmp); 89 } 90 if (num) { 91 ll_rw_block(READA, num, bha); 92 for (i = 0; i < num; i++) 93 brelse(bha[i]); 94 } 95 } 96 } else if (fibh->sbh != fibh->ebh) { 97 brelse(fibh->sbh); 98 fibh->sbh = fibh->ebh; 99 } 100 101 fi = udf_get_fileident(fibh->sbh->b_data, dir->i_sb->s_blocksize, 102 &(fibh->eoffset)); 103 104 if (!fi) 105 return NULL; 106 107 *nf_pos += fibh->eoffset - fibh->soffset; 108 109 if (fibh->eoffset <= dir->i_sb->s_blocksize) { 110 memcpy((uint8_t *)cfi, (uint8_t *)fi, 111 sizeof(struct fileIdentDesc)); 112 } else if (fibh->eoffset > dir->i_sb->s_blocksize) { 113 int lextoffset = epos->offset; 114 115 if (udf_next_aext(dir, epos, eloc, elen, 1) != 116 (EXT_RECORDED_ALLOCATED >> 30)) 117 return NULL; 118 119 block = udf_get_lb_pblock(dir->i_sb, eloc, *offset); 120 121 (*offset)++; 122 123 if ((*offset << dir->i_sb->s_blocksize_bits) >= *elen) 124 *offset = 0; 125 else 126 epos->offset = lextoffset; 127 128 fibh->soffset -= dir->i_sb->s_blocksize; 129 fibh->eoffset -= dir->i_sb->s_blocksize; 130 131 fibh->ebh = udf_tread(dir->i_sb, block); 132 if (!fibh->ebh) 133 return NULL; 134 135 if (sizeof(struct fileIdentDesc) > -fibh->soffset) { 136 int fi_len; 137 138 memcpy((uint8_t *)cfi, (uint8_t *)fi, -fibh->soffset); 139 memcpy((uint8_t *)cfi - fibh->soffset, 140 fibh->ebh->b_data, 141 sizeof(struct fileIdentDesc) + fibh->soffset); 142 143 fi_len = (sizeof(struct fileIdentDesc) + 144 cfi->lengthFileIdent + 145 le16_to_cpu(cfi->lengthOfImpUse) + 3) & ~3; 146 147 *nf_pos += fi_len - (fibh->eoffset - fibh->soffset); 148 fibh->eoffset = fibh->soffset + fi_len; 149 } else { 150 memcpy((uint8_t *)cfi, (uint8_t *)fi, 151 sizeof(struct fileIdentDesc)); 152 } 153 } 154 return fi; 155} 156 157struct fileIdentDesc *udf_get_fileident(void *buffer, int bufsize, int *offset) 158{ 159 struct fileIdentDesc *fi; 160 int lengthThisIdent; 161 uint8_t *ptr; 162 int padlen; 163 164 if ((!buffer) || (!offset)) { 165 udf_debug("invalidparms\n, buffer=%p, offset=%p\n", buffer, 166 offset); 167 return NULL; 168 } 169 170 ptr = buffer; 171 172 if ((*offset > 0) && (*offset < bufsize)) 173 ptr += *offset; 174 fi = (struct fileIdentDesc *)ptr; 175 if (fi->descTag.tagIdent != cpu_to_le16(TAG_IDENT_FID)) { 176 udf_debug("0x%x != TAG_IDENT_FID\n", 177 le16_to_cpu(fi->descTag.tagIdent)); 178 udf_debug("offset: %u sizeof: %lu bufsize: %u\n", 179 *offset, (unsigned long)sizeof(struct fileIdentDesc), 180 bufsize); 181 return NULL; 182 } 183 if ((*offset + sizeof(struct fileIdentDesc)) > bufsize) 184 lengthThisIdent = sizeof(struct fileIdentDesc); 185 else 186 lengthThisIdent = sizeof(struct fileIdentDesc) + 187 fi->lengthFileIdent + le16_to_cpu(fi->lengthOfImpUse); 188 189 /* we need to figure padding, too! */ 190 padlen = lengthThisIdent % UDF_NAME_PAD; 191 if (padlen) 192 lengthThisIdent += (UDF_NAME_PAD - padlen); 193 *offset = *offset + lengthThisIdent; 194 195 return fi; 196} 197 198struct short_ad *udf_get_fileshortad(uint8_t *ptr, int maxoffset, uint32_t *offset, 199 int inc) 200{ 201 struct short_ad *sa; 202 203 if ((!ptr) || (!offset)) { 204 printk(KERN_ERR "udf: udf_get_fileshortad() invalidparms\n"); 205 return NULL; 206 } 207 208 if ((*offset + sizeof(struct short_ad)) > maxoffset) 209 return NULL; 210 else { 211 sa = (struct short_ad *)ptr; 212 if (sa->extLength == 0) 213 return NULL; 214 } 215 216 if (inc) 217 *offset += sizeof(struct short_ad); 218 return sa; 219} 220 221struct long_ad *udf_get_filelongad(uint8_t *ptr, int maxoffset, uint32_t *offset, int inc) 222{ 223 struct long_ad *la; 224 225 if ((!ptr) || (!offset)) { 226 printk(KERN_ERR "udf: udf_get_filelongad() invalidparms\n"); 227 return NULL; 228 } 229 230 if ((*offset + sizeof(struct long_ad)) > maxoffset) 231 return NULL; 232 else { 233 la = (struct long_ad *)ptr; 234 if (la->extLength == 0) 235 return NULL; 236 } 237 238 if (inc) 239 *offset += sizeof(struct long_ad); 240 return la; 241} 242