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
  15 struct inode;
  16 struct gfs2_inode;
  17 struct gfs2_inum;
  18
  19 /**
  20  * gfs2_filldir_t - Report a directory entry to the caller of gfs2_dir_read()
  21  * @opaque: opaque data used by the function
  22  * @name: the name of the directory entry
  23  * @length: the length of the name
  24  * @offset: the entry's offset in the directory
  25  * @inum: the inode number the entry points to
  26  * @type: the type of inode the entry points to
  27  *
  28  * Returns: 0 on success, 1 if buffer full
  29  */
  30
  31 typedef int (*gfs2_filldir_t) (void *opaque,
  32                               const char *name, unsigned int length,
  33                               u64 offset,
  34                               struct gfs2_inum_host *inum, unsigned int type);
  35
  36 int gfs2_dir_search(struct inode *dir, const struct qstr *filename,
  37                     struct gfs2_inum_host *inum, unsigned int *type);
  38 int gfs2_dir_add(struct inode *inode, const struct qstr *filename,
  39                  const struct gfs2_inum_host *inum, unsigned int type);
  40 int gfs2_dir_del(struct gfs2_inode *dip, const struct qstr *filename);
  41 int gfs2_dir_read(struct inode *inode, u64 * offset, void *opaque,
  42                   gfs2_filldir_t filldir);
  43 int gfs2_dir_mvino(struct gfs2_inode *dip, const struct qstr *filename,
  44                    struct gfs2_inum_host *new_inum, unsigned int new_type);
  45
  46 int gfs2_dir_exhash_dealloc(struct gfs2_inode *dip);
  47
  48 int gfs2_diradd_alloc_required(struct inode *dir,
  49                                const struct qstr *filename);
  50 int gfs2_dir_get_new_buffer(struct gfs2_inode *ip, u64 block,
  51                             struct buffer_head **bhp);
  52
  53 static inline u32 gfs2_disk_hash(const char *data, int len)
  54 {
  55         return crc32_le((u32)~0, data, len) ^ (u32)~0;
  56 }
  57
  58
  59 static inline void gfs2_str2qstr(struct qstr *name, const char *fname)
  60 {
  61         name->name = fname;
  62         name->len = strlen(fname);
  63         name->hash = gfs2_disk_hash(name->name, name->len);
  64 }
  65
  66 /* N.B. This probably ought to take inum & type as args as well */
  67 static inline void gfs2_qstr2dirent(const struct qstr *name, u16 reclen, struct gfs2_dirent *dent)
  68 {
  69         dent->de_inum.no_addr = cpu_to_be64(0);
  70         dent->de_inum.no_formal_ino = cpu_to_be64(0);
  71         dent->de_hash = cpu_to_be32(name->hash);
  72         dent->de_rec_len = cpu_to_be16(reclen);
  73         dent->de_name_len = cpu_to_be16(name->len);
  74         dent->de_type = cpu_to_be16(0);
  75         memset(dent->__pad, 0, sizeof(dent->__pad));
  76         memcpy(dent + 1, name->name, name->len);
  77 }
  78
  79 #endif /* __DIR_DOT_H__ */