static struct dentry *isofs_export_get_parent(struct dentry *child) { unsigned long parent_block = 0; unsigned long parent_offset = 0; struct inode *child_inode = child->d_inode; struct iso_inode_info *e_child_inode = ISOFS_I(child_inode); struct iso_directory_record *de = NULL; struct buffer_head * bh = NULL; struct dentry *rv = NULL; if (!S_ISDIR(child_inode->i_mode)) { printk(KERN_ERR "isofs: isofs_export_get_parent(): " "child is not a directory!\n"); rv = ERR_PTR(-EACCES); goto out; } if (e_child_inode->i_iget5_offset != 0) { printk(KERN_ERR "isofs: isofs_export_get_parent(): " "child directory not normalized!\n"); rv = ERR_PTR(-EACCES); goto out; } parent_block = e_child_inode->i_iget5_block; bh = sb_bread(child_inode->i_sb, parent_block); if (bh == NULL) { rv = ERR_PTR(-EACCES); goto out; } de = (struct iso_directory_record*)bh->b_data; parent_offset = (unsigned long)isonum_711(de->length); de = (struct iso_directory_record*)(bh->b_data + parent_offset); if ((isonum_711(de->name_len) != 1) || (de->name[0] != 1)) { printk(KERN_ERR "isofs: Unable to find the \"..\" " "directory for NFS.\n"); rv = ERR_PTR(-EACCES); goto out; } isofs_normalize_block_and_offset(de, &parent_block, &parent_offset); rv = d_obtain_alias(isofs_iget(child_inode->i_sb, parent_block, parent_offset)); out: if (bh) brelse(bh); return rv; }
/* * isofs_find_entry() * * finds an entry in the specified directory with the wanted name. It * returns the inode number of the found entry, or 0 on error. */ static unsigned long isofs_find_entry(struct inode *dir, struct dentry *dentry, unsigned long *block_rv, unsigned long* offset_rv, char * tmpname, struct iso_directory_record * tmpde) { unsigned long bufsize = ISOFS_BUFFER_SIZE(dir); unsigned char bufbits = ISOFS_BUFFER_BITS(dir); unsigned long block, f_pos, offset, block_saved, offset_saved; struct buffer_head * bh = NULL; struct isofs_sb_info *sbi = ISOFS_SB(dir->i_sb); if (!ISOFS_I(dir)->i_first_extent) return 0; f_pos = 0; offset = 0; block = 0; while (f_pos < dir->i_size) { struct iso_directory_record * de; int de_len, match, i, dlen; char *dpnt; if (!bh) { bh = isofs_bread(dir, block); if (!bh) return 0; } de = (struct iso_directory_record *) (bh->b_data + offset); de_len = *(unsigned char *) de; if (!de_len) { brelse(bh); bh = NULL; f_pos = (f_pos + ISOFS_BLOCK_SIZE) & ~(ISOFS_BLOCK_SIZE - 1); block = f_pos >> bufbits; offset = 0; continue; } block_saved = bh->b_blocknr; offset_saved = offset; offset += de_len; f_pos += de_len; /* Make sure we have a full directory entry */ if (offset >= bufsize) { int slop = bufsize - offset + de_len; memcpy(tmpde, de, slop); offset &= bufsize - 1; block++; brelse(bh); bh = NULL; if (offset) { bh = isofs_bread(dir, block); if (!bh) return 0; memcpy((void *) tmpde + slop, bh->b_data, offset); } de = tmpde; } dlen = de->name_len[0]; dpnt = de->name; if (sbi->s_rock && ((i = get_rock_ridge_filename(de, tmpname, dir)))) { dlen = i; /* possibly -1 */ dpnt = tmpname; #ifdef CONFIG_JOLIET } else if (sbi->s_joliet_level) { dlen = get_joliet_filename(de, tmpname, dir); dpnt = tmpname; #endif } else if (sbi->s_mapping == 'a') { dlen = get_acorn_filename(de, tmpname, dir); dpnt = tmpname; } else if (sbi->s_mapping == 'n') { dlen = isofs_name_translate(de, tmpname, dir); dpnt = tmpname; } /* * Skip hidden or associated files unless unhide is set */ match = 0; if (dlen > 0 && (!(de->flags[-sbi->s_high_sierra] & 5) || sbi->s_unhide == 'y')) { match = (isofs_cmp(dentry,dpnt,dlen) == 0); } if (match) { isofs_normalize_block_and_offset(de, &block_saved, &offset_saved); *block_rv = block_saved; *offset_rv = offset_saved; if (bh) brelse(bh); return 1; } }
/* This function is surprisingly simple. The trick is understanding * that "child" is always a directory. So, to find its parent, you * simply need to find its ".." entry, normalize its block and offset, * and return the underlying inode. See the comments for * isofs_normalize_block_and_offset(). */ static struct dentry *isofs_export_get_parent(struct dentry *child) { unsigned long parent_block = 0; unsigned long parent_offset = 0; struct inode *child_inode = child->d_inode; struct iso_inode_info *e_child_inode = ISOFS_I(child_inode); struct iso_directory_record *de = NULL; struct buffer_head * bh = NULL; struct dentry *rv = NULL; /* "child" must always be a directory. */ if (!S_ISDIR(child_inode->i_mode)) { printk(KERN_ERR "isofs: isofs_export_get_parent(): " "child is not a directory!\n"); rv = ERR_PTR(-EACCES); goto out; } /* It is an invariant that the directory offset is zero. If * it is not zero, it means the directory failed to be * normalized for some reason. */ if (e_child_inode->i_iget5_offset != 0) { printk(KERN_ERR "isofs: isofs_export_get_parent(): " "child directory not normalized!\n"); rv = ERR_PTR(-EACCES); goto out; } /* The child inode has been normalized such that its * i_iget5_block value points to the "." entry. Fortunately, * the ".." entry is located in the same block. */ parent_block = e_child_inode->i_iget5_block; /* Get the block in question. */ bh = sb_bread(child_inode->i_sb, parent_block); if (bh == NULL) { rv = ERR_PTR(-EACCES); goto out; } /* This is the "." entry. */ de = (struct iso_directory_record*)bh->b_data; /* The ".." entry is always the second entry. */ parent_offset = (unsigned long)isonum_711(de->length); de = (struct iso_directory_record*)(bh->b_data + parent_offset); /* Verify it is in fact the ".." entry. */ if ((isonum_711(de->name_len) != 1) || (de->name[0] != 1)) { printk(KERN_ERR "isofs: Unable to find the \"..\" " "directory for NFS.\n"); rv = ERR_PTR(-EACCES); goto out; } /* Normalize */ isofs_normalize_block_and_offset(de, &parent_block, &parent_offset); rv = d_obtain_alias(isofs_iget(child_inode->i_sb, parent_block, parent_offset)); out: if (bh) brelse(bh); return rv; }