LXR linux/fs/gfs2/dir.h

   1/*
   2 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3 * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
   4 *
   5 * This copyrighted material is made available to anyone wishing to use,
   6 * modify, copy, or redistribute it subject to the terms and conditions
   7 * of the GNU General Public License version 2.
   8 */
   9
  10#ifndef __DIR_DOT_H__
  11#define __DIR_DOT_H__
  12
  13#include <linux/dcache.h>
  14#include <linux/crc32.h>
  15
  16struct inode;
  17struct gfs2_inode;
  18struct gfs2_inum;
  19
  20extern struct inode *gfs2_dir_search(struct inode *dir,
  21                                     const struct qstr *filename,
  22                                     bool fail_on_exist);
  23extern int gfs2_dir_check(struct inode *dir, const struct qstr *filename,
  24                          const struct gfs2_inode *ip);
  25extern int gfs2_dir_add(struct inode *inode, const struct qstr *filename,
  26                        const struct gfs2_inode *ip);
  27extern int gfs2_dir_del(struct gfs2_inode *dip, const struct dentry *dentry);
  28extern int gfs2_dir_read(struct inode *inode, struct dir_context *ctx,
  29                         struct file_ra_state *f_ra);
  30extern int gfs2_dir_mvino(struct gfs2_inode *dip, const struct qstr *filename,
  31                          const struct gfs2_inode *nip, unsigned int new_type);
  32
  33extern int gfs2_dir_exhash_dealloc(struct gfs2_inode *dip);
  34
  35extern int gfs2_diradd_alloc_required(struct inode *dir,
  36                                      const struct qstr *filename);
  37extern int gfs2_dir_get_new_buffer(struct gfs2_inode *ip, u64 block,
  38                                   struct buffer_head **bhp);
  39extern void gfs2_dir_hash_inval(struct gfs2_inode *ip);
  40
  41static inline u32 gfs2_disk_hash(const char *data, int len)
  42{
  43        return crc32_le((u32)~0, data, len) ^ (u32)~0;
  44}
  45
  46
  47static inline void gfs2_str2qstr(struct qstr *name, const char *fname)
  48{
  49        name->name = fname;
  50        name->len = strlen(fname);
  51        name->hash = gfs2_disk_hash(name->name, name->len);
  52}
  53
  54/* N.B. This probably ought to take inum & type as args as well */
  55static inline void gfs2_qstr2dirent(const struct qstr *name, u16 reclen, struct gfs2_dirent *dent)
  56{
  57        dent->de_inum.no_addr = cpu_to_be64(0);
  58        dent->de_inum.no_formal_ino = cpu_to_be64(0);
  59        dent->de_hash = cpu_to_be32(name->hash);
  60        dent->de_rec_len = cpu_to_be16(reclen);
  61        dent->de_name_len = cpu_to_be16(name->len);
  62        dent->de_type = cpu_to_be16(0);
  63        memset(dent->__pad, 0, sizeof(dent->__pad));
  64        memcpy(dent + 1, name->name, name->len);
  65}
  66
  67extern struct qstr gfs2_qdot;
  68extern struct qstr gfs2_qdotdot;
  69
  70#endif /* __DIR_DOT_H__ */
  71