fs/qnx4/dir.c

   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 *filp, void *dirent, filldir_t filldir)
  18 {
  19         struct inode *inode = file_inode(filp);
  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 "filp->f_pos         = %ld\n", (long) filp->f_pos));
  30
  31         while (filp->f_pos < inode->i_size) {
  32                 blknum = qnx4_block_map( inode, filp->f_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                         break;
  37                 }
  38                 ix = (int)(filp->f_pos >> QNX4_DIR_ENTRY_SIZE_BITS) % QNX4_INODES_PER_BLOCK;
  39                 while (ix < QNX4_INODES_PER_BLOCK) {
  40                         offset = ix * QNX4_DIR_ENTRY_SIZE;
  41                         de = (struct qnx4_inode_entry *) (bh->b_data + offset);
  42                         size = strlen(de->di_fname);
  43                         if (size) {
  44                                 if ( !( de->di_status & QNX4_FILE_LINK ) && size > QNX4_SHORT_NAME_MAX )
  45                                         size = QNX4_SHORT_NAME_MAX;
  46                                 else if ( size > QNX4_NAME_MAX )
  47                                         size = QNX4_NAME_MAX;
  48
  49                                 if ( ( de->di_status & (QNX4_FILE_USED|QNX4_FILE_LINK) ) != 0 ) {
  50                                         QNX4DEBUG((KERN_INFO "qnx4_readdir:%.*s\n", size, de->di_fname));
  51                                         if ( ( de->di_status & QNX4_FILE_LINK ) == 0 )
  52                                                 ino = blknum * QNX4_INODES_PER_BLOCK + ix - 1;
  53                                         else {
  54                                                 le  = (struct qnx4_link_info*)de;
  55                                                 ino = ( le32_to_cpu(le->dl_inode_blk) - 1 ) *
  56                                                         QNX4_INODES_PER_BLOCK +
  57                                                         le->dl_inode_ndx;
  58                                         }
  59                                         if (filldir(dirent, de->di_fname, size, filp->f_pos, ino, DT_UNKNOWN) < 0) {
  60                                                 brelse(bh);
  61                                                 goto out;
  62                                         }
  63                                 }
  64                         }
  65                         ix++;
  66                         filp->f_pos += QNX4_DIR_ENTRY_SIZE;
  67                 }
  68                 brelse(bh);
  69         }
  70 out:
  71         return 0;
  72 }
  73
  74 const struct file_operations qnx4_dir_operations =
  75 {
  76         .llseek         = generic_file_llseek,
  77         .read           = generic_read_dir,
  78         .readdir        = qnx4_readdir,
  79         .fsync          = generic_file_fsync,
  80 };
  81
  82 const struct inode_operations qnx4_dir_inode_operations =
  83 {
  84         .lookup         = qnx4_lookup,
  85 };