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/smp_lock.h>
  15 #include <linux/buffer_head.h>
  16 #include "qnx4.h"
  17
  18 static int qnx4_readdir(struct file *filp, void *dirent, filldir_t filldir)
  19 {
  20         struct inode *inode = filp->f_path.dentry->d_inode;
  21         unsigned int offset;
  22         struct buffer_head *bh;
  23         struct qnx4_inode_entry *de;
  24         struct qnx4_link_info *le;
  25         unsigned long blknum;
  26         int ix, ino;
  27         int size;
  28
  29         QNX4DEBUG(("qnx4_readdir:i_size = %ld\n", (long) inode->i_size));
  30         QNX4DEBUG(("filp->f_pos         = %ld\n", (long) filp->f_pos));
  31
  32         lock_kernel();
  33
  34         while (filp->f_pos < inode->i_size) {
  35                 blknum = qnx4_block_map( inode, filp->f_pos >> QNX4_BLOCK_SIZE_BITS );
  36                 bh = sb_bread(inode->i_sb, blknum);
  37                 if(bh==NULL) {
  38                         printk(KERN_ERR "qnx4_readdir: bread failed (%ld)\n", blknum);
  39                         break;
  40                 }
  41                 ix = (int)(filp->f_pos >> QNX4_DIR_ENTRY_SIZE_BITS) % QNX4_INODES_PER_BLOCK;
  42                 while (ix < QNX4_INODES_PER_BLOCK) {
  43                         offset = ix * QNX4_DIR_ENTRY_SIZE;
  44                         de = (struct qnx4_inode_entry *) (bh->b_data + offset);
  45                         size = strlen(de->di_fname);
  46                         if (size) {
  47                                 if ( !( de->di_status & QNX4_FILE_LINK ) && size > QNX4_SHORT_NAME_MAX )
  48                                         size = QNX4_SHORT_NAME_MAX;
  49                                 else if ( size > QNX4_NAME_MAX )
  50                                         size = QNX4_NAME_MAX;
  51
  52                                 if ( ( de->di_status & (QNX4_FILE_USED|QNX4_FILE_LINK) ) != 0 ) {
  53                                         QNX4DEBUG(("qnx4_readdir:%.*s\n", size, de->di_fname));
  54                                         if ( ( de->di_status & QNX4_FILE_LINK ) == 0 )
  55                                                 ino = blknum * QNX4_INODES_PER_BLOCK + ix - 1;
  56                                         else {
  57                                                 le  = (struct qnx4_link_info*)de;
  58                                                 ino = ( le32_to_cpu(le->dl_inode_blk) - 1 ) *
  59                                                         QNX4_INODES_PER_BLOCK +
  60                                                         le->dl_inode_ndx;
  61                                         }
  62                                         if (filldir(dirent, de->di_fname, size, filp->f_pos, ino, DT_UNKNOWN) < 0) {
  63                                                 brelse(bh);
  64                                                 goto out;
  65                                         }
  66                                 }
  67                         }
  68                         ix++;
  69                         filp->f_pos += QNX4_DIR_ENTRY_SIZE;
  70                 }
  71                 brelse(bh);
  72         }
  73 out:
  74         unlock_kernel();
  75         return 0;
  76 }
  77
  78 const struct file_operations qnx4_dir_operations =
  79 {
  80         .read           = generic_read_dir,
  81         .readdir        = qnx4_readdir,
  82         .fsync          = simple_fsync,
  83 };
  84
  85 const struct inode_operations qnx4_dir_inode_operations =
  86 {
  87         .lookup         = qnx4_lookup,
  88 };