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