fs/gfs2/dir.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   4  * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
   5  */
   6
   7 #ifndef __DIR_DOT_H__
   8 #define __DIR_DOT_H__
   9
  10 #include <linux/dcache.h>
  11 #include <linux/crc32.h>
  12
  13 struct inode;
  14 struct gfs2_inode;
  15 struct gfs2_inum;
  16 struct buffer_head;
  17 struct gfs2_dirent;
  18
  19 struct gfs2_diradd {
  20         unsigned nr_blocks;
  21         struct gfs2_dirent *dent;
  22         struct buffer_head *bh;
  23         int save_loc;
  24 };
  25
  26 struct inode *gfs2_dir_search(struct inode *dir,
  27                               const struct qstr *filename,
  28                               bool fail_on_exist);
  29 int gfs2_dir_check(struct inode *dir, const struct qstr *filename,
  30                    const struct gfs2_inode *ip);
  31 int gfs2_dir_add(struct inode *inode, const struct qstr *filename,
  32                  const struct gfs2_inode *ip, struct gfs2_diradd *da);
  33 static inline void gfs2_dir_no_add(struct gfs2_diradd *da)
  34 {
  35         brelse(da->bh);
  36         da->bh = NULL;
  37 }
  38 int gfs2_dir_del(struct gfs2_inode *dip, const struct dentry *dentry);
  39 int gfs2_dir_read(struct inode *inode, struct dir_context *ctx,
  40                   struct file_ra_state *f_ra);
  41 int gfs2_dir_mvino(struct gfs2_inode *dip, const struct qstr *filename,
  42                    const struct gfs2_inode *nip, unsigned int new_type);
  43
  44 int gfs2_dir_exhash_dealloc(struct gfs2_inode *dip);
  45
  46 int gfs2_diradd_alloc_required(struct inode *dir,
  47                                const struct qstr *filename,
  48                                struct gfs2_diradd *da);
  49 int gfs2_dir_get_new_buffer(struct gfs2_inode *ip, u64 block,
  50                             struct buffer_head **bhp);
  51 void gfs2_dir_hash_inval(struct gfs2_inode *ip);
  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 extern struct qstr gfs2_qdot;
  80 extern struct qstr gfs2_qdotdot;
  81
  82 #endif /* __DIR_DOT_H__ */