LXR linux/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
  23static int qnx4_readdir(struct file *filp, void *dirent, filldir_t filldir)
  24{
  25        struct inode *inode = filp->f_path.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        }
  78out:
  79        unlock_kernel();
  80        return 0;
  81}
  82
  83const struct file_operations qnx4_dir_operations =
  84{
  85        .read           = generic_read_dir,
  86        .readdir        = qnx4_readdir,
  87        .fsync          = file_fsync,
  88};
  89
  90const 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};
  99