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/config.h>
  15 #include <linux/string.h>
  16 #include <linux/errno.h>
  17 #include <linux/fs.h>
  18 #include <linux/qnx4_fs.h>
  19 #include <linux/stat.h>
  20 #include <linux/smp_lock.h>
  21 #include <linux/buffer_head.h>
  22
  23
  24 static int qnx4_readdir(struct file *filp, void *dirent, filldir_t filldir)
  25 {
  26         struct inode *inode = filp->f_dentry->d_inode;
  27         unsigned int offset;
  28         struct buffer_head *bh;
  29         struct qnx4_inode_entry *de;
  30         struct qnx4_link_info *le;
  31         unsigned long blknum;
  32         int ix, ino;
  33         int size;
  34
  35         QNX4DEBUG(("qnx4_readdir:i_size = %ld\n", (long) inode->i_size));
  36         QNX4DEBUG(("filp->f_pos         = %ld\n", (long) filp->f_pos));
  37
  38         lock_kernel();
  39
  40         while (filp->f_pos < inode->i_size) {
  41                 blknum = qnx4_block_map( inode, filp->f_pos >> QNX4_BLOCK_SIZE_BITS );
  42                 bh = sb_bread(inode->i_sb, blknum);
  43                 if(bh==NULL) {
  44                         printk(KERN_ERR "qnx4_readdir: bread failed (%ld)\n", blknum);
  45                         break;
  46                 }
  47                 ix = (int)(filp->f_pos >> QNX4_DIR_ENTRY_SIZE_BITS) % QNX4_INODES_PER_BLOCK;
  48                 while (ix < QNX4_INODES_PER_BLOCK) {
  49                         offset = ix * QNX4_DIR_ENTRY_SIZE;
  50                         de = (struct qnx4_inode_entry *) (bh->b_data + offset);
  51                         size = strlen(de->di_fname);
  52                         if (size) {
  53                                 if ( !( de->di_status & QNX4_FILE_LINK ) && size > QNX4_SHORT_NAME_MAX )
  54                                         size = QNX4_SHORT_NAME_MAX;
  55                                 else if ( size > QNX4_NAME_MAX )
  56                                         size = QNX4_NAME_MAX;
  57
  58                                 if ( ( de->di_status & (QNX4_FILE_USED|QNX4_FILE_LINK) ) != 0 ) {
  59                                         QNX4DEBUG(("qnx4_readdir:%.*s\n", size, de->di_fname));
  60                                         if ( ( de->di_status & QNX4_FILE_LINK ) == 0 )
  61                                                 ino = blknum * QNX4_INODES_PER_BLOCK + ix - 1;
  62                                         else {
  63                                                 le  = (struct qnx4_link_info*)de;
  64                                                 ino = ( le32_to_cpu(le->dl_inode_blk) - 1 ) *
  65                                                         QNX4_INODES_PER_BLOCK +
  66                                                         le->dl_inode_ndx;
  67                                         }
  68                                         if (filldir(dirent, de->di_fname, size, filp->f_pos, ino, DT_UNKNOWN) < 0) {
  69                                                 brelse(bh);
  70                                                 goto out;
  71                                         }
  72                                 }
  73                         }
  74                         ix++;
  75                         filp->f_pos += QNX4_DIR_ENTRY_SIZE;
  76                 }
  77                 brelse(bh);
  78         }
  79 out:
  80         unlock_kernel();
  81         return 0;
  82 }
  83
  84 const struct file_operations qnx4_dir_operations =
  85 {
  86         .read           = generic_read_dir,
  87         .readdir        = qnx4_readdir,
  88         .fsync          = file_fsync,
  89 };
  90
  91 struct inode_operations qnx4_dir_inode_operations =
  92 {
  93         .lookup         = qnx4_lookup,
  94 #ifdef CONFIG_QNX4FS_RW
  95         .create         = qnx4_create,
  96         .unlink         = qnx4_unlink,
  97         .rmdir          = qnx4_rmdir,
  98 #endif
  99 };