diff options
Diffstat (limited to 'fs/udf/directory.c')
| -rw-r--r-- | fs/udf/directory.c | 242 |
1 files changed, 242 insertions, 0 deletions
diff --git a/fs/udf/directory.c b/fs/udf/directory.c new file mode 100644 index 000000000..16bcf2c6b --- /dev/null +++ b/fs/udf/directory.c @@ -0,0 +1,242 @@ +/* + * directory.c + * + * PURPOSE + * Directory related functions + * + * COPYRIGHT + * This file is distributed under the terms of the GNU General Public + * License (GPL). Copies of the GPL can be obtained from: + * ftp://prep.ai.mit.edu/pub/gnu/GPL + * Each contributing author retains all rights to their own work. + */ + +#include "udfdecl.h" +#include "udf_i.h" + +#include <linux/fs.h> +#include <linux/string.h> +#include <linux/bio.h> + +struct fileIdentDesc *udf_fileident_read(struct inode *dir, loff_t *nf_pos, + struct udf_fileident_bh *fibh, + struct fileIdentDesc *cfi, + struct extent_position *epos, + struct kernel_lb_addr *eloc, uint32_t *elen, + sector_t *offset) +{ + struct fileIdentDesc *fi; + int i, num; + udf_pblk_t block; + struct buffer_head *tmp, *bha[16]; + struct udf_inode_info *iinfo = UDF_I(dir); + + fibh->soffset = fibh->eoffset; + + if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) { + fi = udf_get_fileident(iinfo->i_data - + (iinfo->i_efe ? + sizeof(struct extendedFileEntry) : + sizeof(struct fileEntry)), + dir->i_sb->s_blocksize, + &(fibh->eoffset)); + if (!fi) + return NULL; + + *nf_pos += fibh->eoffset - fibh->soffset; + + memcpy((uint8_t *)cfi, (uint8_t *)fi, + sizeof(struct fileIdentDesc)); + + return fi; + } + + if (fibh->eoffset == dir->i_sb->s_blocksize) { + uint32_t lextoffset = epos->offset; + unsigned char blocksize_bits = dir->i_sb->s_blocksize_bits; + + if (udf_next_aext(dir, epos, eloc, elen, 1) != + (EXT_RECORDED_ALLOCATED >> 30)) + return NULL; + + block = udf_get_lb_pblock(dir->i_sb, eloc, *offset); + + (*offset)++; + + if ((*offset << blocksize_bits) >= *elen) + *offset = 0; + else + epos->offset = lextoffset; + + brelse(fibh->sbh); + fibh->sbh = fibh->ebh = udf_tread(dir->i_sb, block); + if (!fibh->sbh) + return NULL; + fibh->soffset = fibh->eoffset = 0; + + if (!(*offset & ((16 >> (blocksize_bits - 9)) - 1))) { + i = 16 >> (blocksize_bits - 9); + if (i + *offset > (*elen >> blocksize_bits)) + i = (*elen >> blocksize_bits)-*offset; + for (num = 0; i > 0; i--) { + block = udf_get_lb_pblock(dir->i_sb, eloc, + *offset + i); + tmp = udf_tgetblk(dir->i_sb, block); + if (tmp && !buffer_uptodate(tmp) && + !buffer_locked(tmp)) + bha[num++] = tmp; + else + brelse(tmp); + } + if (num) { + bh_readahead_batch(num, bha, REQ_RAHEAD); + for (i = 0; i < num; i++) + brelse(bha[i]); + } + } + } else if (fibh->sbh != fibh->ebh) { + brelse(fibh->sbh); + fibh->sbh = fibh->ebh; + } + + fi = udf_get_fileident(fibh->sbh->b_data, dir->i_sb->s_blocksize, + &(fibh->eoffset)); + + if (!fi) + return NULL; + + *nf_pos += fibh->eoffset - fibh->soffset; + + if (fibh->eoffset <= dir->i_sb->s_blocksize) { + memcpy((uint8_t *)cfi, (uint8_t *)fi, + sizeof(struct fileIdentDesc)); + } else if (fibh->eoffset > dir->i_sb->s_blocksize) { + uint32_t lextoffset = epos->offset; + + if (udf_next_aext(dir, epos, eloc, elen, 1) != + (EXT_RECORDED_ALLOCATED >> 30)) + return NULL; + + block = udf_get_lb_pblock(dir->i_sb, eloc, *offset); + + (*offset)++; + + if ((*offset << dir->i_sb->s_blocksize_bits) >= *elen) + *offset = 0; + else + epos->offset = lextoffset; + + fibh->soffset -= dir->i_sb->s_blocksize; + fibh->eoffset -= dir->i_sb->s_blocksize; + + fibh->ebh = udf_tread(dir->i_sb, block); + if (!fibh->ebh) + return NULL; + + if (sizeof(struct fileIdentDesc) > -fibh->soffset) { + int fi_len; + + memcpy((uint8_t *)cfi, (uint8_t *)fi, -fibh->soffset); + memcpy((uint8_t *)cfi - fibh->soffset, + fibh->ebh->b_data, + sizeof(struct fileIdentDesc) + fibh->soffset); + + fi_len = udf_dir_entry_len(cfi); + *nf_pos += fi_len - (fibh->eoffset - fibh->soffset); + fibh->eoffset = fibh->soffset + fi_len; + } else { + memcpy((uint8_t *)cfi, (uint8_t *)fi, + sizeof(struct fileIdentDesc)); + } + } + /* Got last entry outside of dir size - fs is corrupted! */ + if (*nf_pos > dir->i_size) + return NULL; + return fi; +} + +struct fileIdentDesc *udf_get_fileident(void *buffer, int bufsize, int *offset) +{ + struct fileIdentDesc *fi; + int lengthThisIdent; + uint8_t *ptr; + int padlen; + + if ((!buffer) || (!offset)) { + udf_debug("invalidparms, buffer=%p, offset=%p\n", + buffer, offset); + return NULL; + } + + ptr = buffer; + + if ((*offset > 0) && (*offset < bufsize)) + ptr += *offset; + fi = (struct fileIdentDesc *)ptr; + if (fi->descTag.tagIdent != cpu_to_le16(TAG_IDENT_FID)) { + udf_debug("0x%x != TAG_IDENT_FID\n", + le16_to_cpu(fi->descTag.tagIdent)); + udf_debug("offset: %d sizeof: %lu bufsize: %d\n", + *offset, (unsigned long)sizeof(struct fileIdentDesc), + bufsize); + return NULL; + } + if ((*offset + sizeof(struct fileIdentDesc)) > bufsize) + lengthThisIdent = sizeof(struct fileIdentDesc); + else + lengthThisIdent = sizeof(struct fileIdentDesc) + + fi->lengthFileIdent + le16_to_cpu(fi->lengthOfImpUse); + + /* we need to figure padding, too! */ + padlen = lengthThisIdent % UDF_NAME_PAD; + if (padlen) + lengthThisIdent += (UDF_NAME_PAD - padlen); + *offset = *offset + lengthThisIdent; + + return fi; +} + +struct short_ad *udf_get_fileshortad(uint8_t *ptr, int maxoffset, uint32_t *offset, + int inc) +{ + struct short_ad *sa; + + if ((!ptr) || (!offset)) { + pr_err("%s: invalidparms\n", __func__); + return NULL; + } + + if ((*offset + sizeof(struct short_ad)) > maxoffset) + return NULL; + else { + sa = (struct short_ad *)ptr; + if (sa->extLength == 0) + return NULL; + } + + if (inc) + *offset += sizeof(struct short_ad); + return sa; +} + +struct long_ad *udf_get_filelongad(uint8_t *ptr, int maxoffset, uint32_t *offset, int inc) +{ + struct long_ad *la; + + if ((!ptr) || (!offset)) { + pr_err("%s: invalidparms\n", __func__); + return NULL; + } + + if ((*offset + sizeof(struct long_ad)) > maxoffset) + return NULL; + else { + la = (struct long_ad *)ptr; + if (la->extLength == 0) + return NULL; + } + + if (inc) + *offset += sizeof(struct long_ad); + return la; +} |