1 /* 2 * QNX4 file system, Linux implementation. 3 * 4 * Version : 0.2.1 5 * 6 * Using parts of the xiafs filesystem. 7 * 8 * History : 9 * 10 * 28-05-1998 by Richard Frowijn : first release. 11 * 20-06-1998 by Frank Denis : Linux 2.1.99+ & dcache support. 12 */ 13 14 #include <linux/buffer_head.h> 15 #include "qnx4.h" 16 17 static int qnx4_readdir(struct file *file, struct dir_context *ctx) 18 { 19 struct inode *inode = file_inode(file); 20 unsigned int offset; 21 struct buffer_head *bh; 22 struct qnx4_inode_entry *de; 23 struct qnx4_link_info *le; 24 unsigned long blknum; 25 int ix, ino; 26 int size; 27 28 QNX4DEBUG((KERN_INFO "qnx4_readdir:i_size = %ld\n", (long) inode->i_size)); 29 QNX4DEBUG((KERN_INFO "pos = %ld\n", (long) ctx->pos)); 30 31 while (ctx->pos < inode->i_size) { 32 blknum = qnx4_block_map(inode, ctx->pos >> QNX4_BLOCK_SIZE_BITS); 33 bh = sb_bread(inode->i_sb, blknum); 34 if (bh == NULL) { 35 printk(KERN_ERR "qnx4_readdir: bread failed (%ld)\n", blknum); 36 return 0; 37 } 38 ix = (ctx->pos >> QNX4_DIR_ENTRY_SIZE_BITS) % QNX4_INODES_PER_BLOCK; 39 for (; ix < QNX4_INODES_PER_BLOCK; ix++, ctx->pos += QNX4_DIR_ENTRY_SIZE) { 40 offset = ix * QNX4_DIR_ENTRY_SIZE; 41 de = (struct qnx4_inode_entry *) (bh->b_data + offset); 42 if (!de->di_fname[0]) 43 continue; 44 if (!(de->di_status & (QNX4_FILE_USED|QNX4_FILE_LINK))) 45 continue; 46 if (!(de->di_status & QNX4_FILE_LINK)) 47 size = QNX4_SHORT_NAME_MAX; 48 else 49 size = QNX4_NAME_MAX; 50 size = strnlen(de->di_fname, size); 51 QNX4DEBUG((KERN_INFO "qnx4_readdir:%.*s\n", size, de->di_fname)); 52 if (!(de->di_status & QNX4_FILE_LINK)) 53 ino = blknum * QNX4_INODES_PER_BLOCK + ix - 1; 54 else { 55 le = (struct qnx4_link_info*)de; 56 ino = ( le32_to_cpu(le->dl_inode_blk) - 1 ) * 57 QNX4_INODES_PER_BLOCK + 58 le->dl_inode_ndx; 59 } 60 if (!dir_emit(ctx, de->di_fname, size, ino, DT_UNKNOWN)) { 61 brelse(bh); 62 return 0; 63 } 64 } 65 brelse(bh); 66 } 67 return 0; 68 } 69 70 const struct file_operations qnx4_dir_operations = 71 { 72 .llseek = generic_file_llseek, 73 .read = generic_read_dir, 74 .iterate_shared = qnx4_readdir, 75 .fsync = generic_file_fsync, 76 }; 77 78 const struct inode_operations qnx4_dir_inode_operations = 79 { 80 .lookup = qnx4_lookup, 81 }; 82